Untitled - University of Oxford

OFI OCCASIONAL PAPERS
No 49
The Natural Management of Tropical Forests
for Timber and Non-Timber Products
Sarah Laird
1995
ISBN 0 85074 136 X
ISSN 0269 - 5790
Oxford Forestry Institute
Department of Plant Sciences
University of Oxford

Table of Contents
Acknowledgements ii
I. Introduction 1
11. Sustainable Forestry 2
Ill. The Economic Underpinnings of Natural Forest Management 4
- Box 1: Lesser-Known Timber Species 9
- Box 2: The Economic Valuation of Non-Timber Forest Products 10
IV. The Ecologically Sustainable Harvest of Non-Timber Products
from Tropical Forests 11
- Plant Parts Used in Non-Timber Forest Products 14
- Wildlife as a Non-Timber Forest Product 17
V. The Ecological Underpinnings of Natural Forest Management 18
VI. Harvesting Operations in Managed Natural Forest 20
- Box 3: Inventories of Non-Timber Forest Products for
Natural Forest Management 25
VII. Silvicultural Systems for Natural Forest Management 26
- Box 4: Examples of MUlti-purpose Amazonian Species with
Present and Future Potential for Natural Forest Management 33
VIII. Traditional Management of Neotropical Forests for Timber and
Non-Timber Products 35
IX. Natural Forest Management and the Conservation of Biodiversity 38
- The Impact of Natural Forest Management on Wildlife 42
x. Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 45
Bibliography 49
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Acknowledgements
I would like to thank the following for their valuable comments, advice and thoughts on this
document: Trish Shanley, Mike Arnold, Nick Brown, and Peter Kanowski.

I. Introduction
The tenn "non-timber forest products" (NTFPs) describes a wide range of products, including
medicinal plants, fibres, resins, latexes, fruits, foods, construction materials, and bushmeat. The plant
products may be taken from a variety of life forms and plant parts, including reproductive propagules,
plant exudates, vegetative structures, roots and bark. NTFPs may be harvested for subsistence
consumption, for small local markets, or for regional or even international trade. They may have long
histories in traditional resource use, or they may be recently developed, and have applications of
primary importance to industrial cultures. NTFPs may be sourced from high-diversity primary forest,
low diversity "oligarchic" forests, or secondary forests. These forests may be in various states of
repair, and may exist in extractive reserves, indigenous reserves, communally-held and managed
forests, privately-owned lands, reserves demarcated for conservation purposes, timber concessions,
or government lands. NTFPs may be harvested from areas with high population densities with welldeveloped
labour and trade patterns, or in areas that are sparsely populated. Harvesters may be rural
peoples (in which case they might be indigenous, long-term settlers of mixed ethnicity, or recent
immigrants from other rural areas or urban centres), or teams of individuals from urban areas. These
harvesters mayor may not operate under traditional systems of resource management and harvesting
controls. Products might be consumed in rural areas or urban centres. Trade patterns may be complex,
with a variety of intermediaries, or fairly simple. This is all to say that when we speak of "non-timber
forest products" (a term which in itself has been questioned, due to the implied primacy of timber
forest products), we are speaking of many things (Padoch et al., 1992; Pendleton, 1992; Vasquez and
Gentry, 1989).
Timber production can have a number of effects on the production of non-timber forest products.
Destructive harvesting operations can cause direct damage to species in residual stands and those that
make up the understorey and ground cover of forests, many of which are important NTFPs.
Subsequent silvicultural treatments can reduce species diversity by promoting an increased proportion
of commercial species, and removing the competing "undesirables", many of which are important
NTFPs. In some cases, timber species will have important non-timber uses locally, and the overharvesting
of these species for timber will reduce collection of these species for their non-timber uses.
The harvest of NTFPs could, at times, reduce the number and regeneration success of timber species,
as well. For example, if bark is stripped, reproductive propagules over-harvested, or exudates tapped
heavily, growth rates and reproduction of timber species can be impaired.
Timber harvesting and silvicultural treatments, by reducing the structural and species diversity of a
forest, can also produce a number of still largely unknown ecological repercussions. These result in
reductions in numbers of pollinators, seed dispersers, and alterations in plant-herbivore relationships,
and may ultimately produce conditions in which it is difficult for many forest species to regenerate.
A wide range of NTFPs are usually harvested from a given forest, so reductions in species diversity
can directly impact the collection of these products, and the consumption and trade patterns of local
people dependent upon them for their livelihoods and survival.
Timber and non-timber products can be incorporated into multi-purpose systems of natural forest
management that both minimize the negative impacts of timber extraction and capitalize on the many
benefits provided by a range of forest products. Following is a discussion of some of the economic,
cultural and ecological issues involved in this type of system, with particular emphasis on the
Neotropics, and general suggestions for guidelines that might assist with the integration of non-timber
and timber products in forest management.
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11. Sustainable Forestry
Duncan Poore (1989), in his popularly quoted definition of sustainable timber production, describes
"the single most important condition to be met is that nothing should be done that will irreversibly
reduce the potential of the forest to produce marketable timber - that is, there should be no
irreversible loss of soil, soil fertility or genetic potential of marketable species". Sustained yield
timber production implies the management of timber crops so as to produce a continuous flow of
wood output, while safeguarding the productive potential of the forest (Gane, 1992). Sustainable
forestry implies a much broader, multi-sectorial agenda that attempts to "balance use", includes the
production of non-timber as well as timber products, conserves forest ecosystems and the genetic and
species diversity contained within them, and generates income, employment, consumption, and
investment benefits for local forest dwellers, as well as nations (Gane, 1992; Poore, 1989; Barbier,
1987).
While there is a general agreement that ecological and technical abilities are sufficient to achieve
sustainable timber production, it could be questioned whether they are up to the job of sustainable
forestry, as described above. The complexities of natural forest management appear to only multiply
as more knowledge is acquired, and the shifting of priorities from timber production to multiple use
natural forest management carries with it an enormous burden of ignorance. Not only is little known
about the ecological requirements of individual commercial timber species, less still is understood
about non-timber commercial species.
The Supply of Tropical Timber
Global demand for industrial wood has been projected to grow by margins of 15% to 40% over 15
years, and from 35% to 75% over 50 years (Arnold, 1991). Tropical hardwoods from Southeast Asia
currently fonn the bulk of the export market from developing countries, accounting for 84% of the
market in 1981; 14% of these exports come from Africa, and 1% from Latin America (although
forests are logged heavily in Africa and Latin America for regional consumption (Prescott-Allen,
1982; Schmidt, 1991; Repetto and Gillis, 1988)1. Of this, the FAO found in 1985 that over 90%
came from unmanaged natural forest, roughly divided between primary and once-logged forest'. Of
the 800,000,000 ha of forests in IITO producer member countries, only 1,000,000 ha are managed
under sustained yield (Poore, 1989). In the Neotropics, for every 1 ha of tropical moist forest
managed under sustained yield management, 35,000 ha are not (Wadsworth, 1987).
Although plantations will play an increasing role in timber production in tropical countries, alone they
will not be able to satisfy the increasing demand for wood. Plantations must also compete with
agriculture for valuable land and must be near processing industries; they tie up capital - of which
there is often little in these regions; they are vulnerable to attacks by pests and diseases, and are
generally perceived as a risk to investors (Wadsworth, 1987; Schmidt, 1991). Natural forest
1 Regional markets often consume the bulk. of a country's timber. For example, in Brazil, 80% of the wood produced
in Amazonia is consumed by regional markets, with national and international markets making up the remaining 20% (UbI
et ai., 1989).
2 Rotations, regeneration periods, felling cycles, harvestable girth limits, etc. were not based on growth rates and
regeneration requirements of the species, but on the demand for wood, so forests are usually harvested in excess of the
allowable cut, and logging damage tends to be severe (Nair, 1991).

management and plantations of tropical timber, therefore, must play complementary roles in the
production of tropical timber (Schmidt, 1991; Anderson, 1990).
Natural Forest Management
Many of the problems associated with natural forest managemenf result from the limited objectives
set in the past by forest managers 4 • The best way to ensure success in natural tropical forests is to
use as much of the great species and genetic diversity as possible (Gomez-Pompa and Burley, 1991;
Hart, 1980; Clay and Clement, 1993; Gentry, 1992; Hidalgo, 1992). The diversity of tropical forests
has been seen in the past as a major obstacle to its commercial exploitation, and numerous forest
management efforts have failed because they fought against this diversity, rather than capitalized on
it. But natural forests managed for multiple purposes have a number of significant advantages: they
produce a variety of products, and so can flexibly adjust to changing markets for forest products; the
costs of management are significantly lower than more intensive land-use systems; there is less
likelihood of pests, disease, or natural disasters destroying their productive capacity; they are more
easily adapted to local social and cultural conditions; and they maintain the ecological functions of
the forest (Poore and Sayer, 1991; Anderson, 1990). Ultimately, natural forest management provides
the best compromise between the need to use valuable forest resources and the need to conserve
forests and the diversity of species they contain (ITIO, 1992; Salick, 1992). As Schmidt (1991) said,
"is natural forest management uneconomic or is it the only economic alternative?".
Standing tropical forests provide numerous non-timber benefits, including climatic and environmental
services, wild relatives of crops, potential phannaceutical compounds 5 , and numerous non-timber
forest products. Non-timber products like medicines, resins, essential oils, fibres) and foods, generate
large amounts of income in the local and regional markets of tropical countries, and some species,
like rattan, rosewood oil, chicle, and Brazil nuts, are traded widely on the international market 6 • The
non-timber forest products of three areas in Latin America, for example, yielded greater potential
returns!hectare than timber extraction, cattle ranching, and plantation forestry (Peters et al., 1989;
Balick and Mendelssohn, 1992; Grimes et al., 1993). More than 1.5,000,000 people in the Brazilian
Amazon earn the bulk of their living from the extraction of forest products (Richards, 1993). The
3 Natural forest management can be defined as the extraction of some of the forest products without significantly
disturbing the ecosystem as a whole. Forest manipulation and conservation occur through an efficient natural or induced
regeneration of the forest ecosystem, which is only lightly disturbed (Gomez-Pompa and Burley, 1991; Schmidt, 1991).
The sustainable implementation of this system results in the maintenance of ecological processes and significant levels
of biodiversity, and requires the sustainable harvest of non-timber and timber products alike (poore and Sayer, 1991).
4 The failure of sustainable natural forest management has been attributed to a number of factors, including: high
extraction costs (in relation to prices) associated with selective logging; low volume commercial woods available/unit area,
and so low economic returns; lack of understanding of the silvics of tropical tree species, and resulting difficulties in
management; vulnerability to disruptive land uses, such as shifting cultivation; government policies that make sustainedyield
forestry economically unattractive; and forestry agencies that don't effectively regulate forestry practices (UbI et
al., 1989; Anderson, 1990).
s Principe (1992) estimates that the value for prescription and over-the-counter medicines in OEeD countries in 1985
was $43,000,000,000. Additionally, the World Health Organization estimates that the vast majority (80%) of the world's
population depends upon traditional, natural product-based medicines for their primary healthcare.
6 Exports of non-timber forest products from Indonesia reached $125,OOO,OOO/year in the early 1980s. In 1973, nonwood
products accounted for 2.9% of the total forest product export value, but in 1982 had increased to 13.3%. The rattan
industry alone employs 70,000 - 100,000 people, not including collectors (De Jong and Mendelssohn, 1992).
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yields on alternative land-uses for the tropics have been greatly overestimated. Poor soils and
invasions by pests and weeds have led to the failure of most intensive land-use systems (Peters et
al., 1989; Balick and Mendelssohn, 1992). Natural forests can be managed to efficiently utilize the
wide variety of possible forest resources, providing the maximum total benefit over the long run, and
avoiding the environmental degradation associated with many other land-use options in the tropics
(Repetto and Gillis, 1988).
Ill. The Economic Underpinnings of Natural Forest Management
Economics is a way of thinking about problems, not a recipe for solving them - Keynes, 1936
Economic theory suffers from a tendency to assume that the world is a sum of its parts - that if we
objectively understand the many components of a system, we will understand the whole. But in
economics, as in ecology, the reality is far more complex and there exist no "universal truths"; the
"parts" represent constantly co-evolving, dynamic and interdependent relationships, difficult to
understand and impossible to separate from each other in any applicable analysis (Norgaard).
Neoclassical economic theory has for decades determined the type of forestry and "development"
practised in the tropics, promoting national capital accumulation as a measure of a linear type of
"progress".
Microeconomic models utilizing comparative advantage, specialization, and gains from exchange
were employed to increase GNP and per capita incomes, but little "real" development resulted.
Although overall growth was achieved in many countries, it was often at the expense of natural
resource wealth and resulted in only wider gaps between rich and poor (Schwartzman, 1992; Burns,
1986; Barbier, 1987). The concept of development, much as with "sustainability", has been revised
to emphasize meeting the basic needs of the poor, to advocate cultural sensitivity, and to encourage
"grassroots" participation in the development process. In theory, this means that political, social and
cultural values are added to measurements of economic activity when assessing development, and
smaller, adaptive projects are encouraged (Barbier, 1987).
Neoclassical economic theory holds that resources will be efficiently allocated when prices reflect
true resource scarcity, there exists a right of ownership and therefore freedom to trade, and when
consumers have access to information about the total amount of a resource available (National
Research Council, 1992). But tropical forest resources have consistently been undervalued, and their
over-exploitation has been considered net income, rather than a loss of wealth (McNeely, 1988). As
a result, under this system the only biodiversity remaining will be that which is too expensive to
exploit, due to difficulties in access, and too immediately valuable to destroy, such as ground water.
The failure in this system to value biodiversity results from a combination of market failures,
intervention failures, and global appropriations failures (Pearce, 1993), including: biodiversity
provides many non-marketed environmental services (like erosion prevention and flood control), and
supplies "invisible" products (like NTFPs traded only on local markets), and many potential products
(like lesser-known-timber species); government interventions, such as (perverse) incentives, tax
provisions, and tax credits, distort commodity prices and promote short-tenn profits through resource

depletion 7 ; biodiversity and many forests are a "public good" and therefore are not "owned", so can
result in infinite discounting of future costs on the part of users; consumers do not have adequate
access to infonnation about the total value of natural resources and so prices do not reflect scarcity;
timber and some other forest products have long gestation periods, and so the discount rates applied
by current economic planners make its long-term sustainable use appear uneconomic; knowledge of
the multiplicity of potential useful forest species is limited, and so not factored into assessments of
its value; and forest products are most widely used by the poor and politically and economically
powerless (McNeely, 1988; National Research Council, 1992; Pearce, 1992; Barbier, 1987;
Schwartzman, 1992; Repetto and Gillis, 1988; Swanson, 1992; Repetto and Gillis, 1988; Uhl et al.,
1989).
Causal mechanisms also influence the use of forest resources. These might include economic
instruments used to stimulate the economy, property rights 8 , external debt, international trade
policies, the over-valuation of currency, inflation (which encourages cattle ranching, for example,
because cattle are - in effect - inflation-proof), price instability of major export crops, the structure
(time and cost) of concessions, etc. (National Research Council, 1992; Repetto and Gillis, 1988)9.
Direct economic incentives and disincentives can also influence the nature of resource use.
Disincentives for destruction include the posting of environmental bonds by logging companies;
incentives might include the employment of local people in reserved areas (McNeely, 1988).
Proper valuation techniques are necessary for the many timber and non-timber values generated by
tropical forests, and for the appraisal of forestry projects and alternative forest uses. Assessments of
the financial value of various forest management systems does not even roughly approximate the
wider economic value of all benefits (irrespective of who receives them), against all the costs
(irrespective of who bears them) (Leslie, 1987). Foresters have been forced to increase the fmancial
perfonnance of natural forest management by increasing revenues and decreasing costs; silvicultural
systems strive to increase growth rates and yield, shorten rotations and lower treatment and protection
costs; lesser-known species are sought to increase yield per unit area (Leslie, 1987). But forests
provide numerous benefits and excessive exploitation incurs many costs not measured by financial
analysis.
A number of economic valuation techniques have been developed to incorporate non-marketed goods
and services provided by forests, so as to be comparable with values placed on marketable goods.
These include costs of replacement, hedonic price analysis, travel cost methods, and contingent
valuation. These are used to measure both direct and indirect use of a resource (timber, plant
7 For example, in the Brazilian Amazon subsidies and other policy distortions are estimated to have accounted for
at least 30% of all forest altered by 1980. Over the past three decades> 10,000,000 ha of Amazonian rainforest have been
converted to cattle pastures, largely through government policies. For every 1/4 lb. hamburger that cost US$ 0.26 to
produce, the government of Brazil expended US$ 0.22 (Anderson, 1990). From 1970-1988, US$23,OOO,OOO,OOO was spent
subsidizing cattle ranching, agriculture and colonization projects, and the building of roads in the Amazon (Schwartzman,
1992).
8 Private property and communal property rights best protect forest resources in the long-term. Open-access and
insecure land tenure, because they do not guarantee the user any future access, usually results in a "tragedy of the
commons" in which the future is discounted infmitely and user costs are ignored.
9 Mather (1990) suggest that policies for land use systems other than forestry have had a larger impact on forests than
any forestry policy.
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breeding, landscape, recreation, biodiversity, watershed, recreation, etc.), option values (biodiversity,
recreation, potential phannaceuticals, landscape, etc.) and existence values (biodiversity, landscape,
etc.) (Pearce, 1991; 1992).
Standard cost-benefit analysis of the variety of products produced by a forest can also be used in
some cases to provide strong arguments for sustainable use, although Leslie (1987) and others find
it "tactically" naive to fight the battle for natural forest management on financial grounds (National
Research Council, 1992; Pearce, 1991, 1992; Leslie, 1987; ITTO, 1990) But because most policymakers
use cost-benefit analysis when making decisions about land-use options, it is important that
these be expanded to include the range of marketable products, including NTFPs. However, because
the trade in NTFPs is largely local or regional and takes place in the "infonnal sector", few records
exist on their economic value; as a result, although NTFPs make up a significant percentage of the
actual value of the forests, they are not figured in to policy and management decisions (Padoch et
al., 1992; Cleary, 1992).
Comparative economics has been used to successfully demonstrate the economic importance of
conservation and multi-purpose use of natural forests, by demonstrating the superior economic
perfonnance of NTFPs when compared with other land-use options in tropical forests (Peters et al.,
1989; Balick and Mendelssohn, 1992; Godoy and Lubowski, 1992; Falconer, 1990; De Beer and
McDermott, 1989; Phillips, 1992; Grimes et al., 1993). Additionally, the harvest of NTFPs throughout
the economically "unproductive" building phase of timber trees can subsidize silvicultural and
management expenses, and can lessen the blow struck to financial analyses of natural forest
management by compounded interest 10 • For local peoples, non-timber products can provide
consistent, if relatively small, sources of income, complemented by the periodic concentration of
capital produced by the felling of timber (Leslie, 1987; Salick, 1992; Reining and Heinzman, 1992;
Malhotra et al., 1991).
But valuation is clearly not enough. Peters et al. (1989) note that, although NTFPs have a superior
economic value in the area of Peru they studied, timber continues to be considered of primary
importance, largely due to its sale on international markets and generation of foreign exchange.
NTFPs, on the other hand, are collected and sold in local markets by an incalculable number of
subsistence farmers, forest collectors, middlemen and shop owners. These decentralized trade
networks are extremely hard to monitor and easy to ignore (Peters et al., 1989; Padoch, 1992).
Some Socioeconomic Considerations for the Sustainable Use of NTFPs
In order for non-timber forest products to be incorporated into natural forest management and
generate sustainable income for local peoples, a number of basic issues must be addressed ll . These
include: land tenure, fluctuations in markets, local value-added processing, over-harvesting of species,
transportation, and the expansion of markets overseas.
10 For example, rattan species have been planted in logged-over forest in Southeast Asia to both "rehabilitate"
degraded forests and provide a significant interim income while the forest recovers from logging pressure (Sayer, 1991).
11 Ifnatural forest management is to succeed, forest managers must better understand the ideological assumptions from
which their decisions are made, and correct deficiencies in their understanding of the socioeconomic context in which
forestry projects operate. This is particularly important when incorporating NTFPs into forest management, because
ignorance of the socioeconomic dynamics of these complex collection and trading systems could lead to projects that
would restrict and potentially damage local livelihoods, rather than enhance the productivity of a forest (Cleary, 1992).

Land Tenure
Land tenure and resource rights for forest residents are essential prerequisites to sustainability in an
economy based on natural forest management that utilizes a wide range of products over long periods
of time (Clay and Clement, 1993; Schwartzman, 1992; Allegreti, 1990; Cleary, 1992; De long and
Mendelssohn, 1992). Because of the scattered nature of most species in the tropical forest, and the
low productivity per unit area, sustainable, lower-yielding systems are only attractive if collectors
retain long-tenn security of access to the forest and its resources (Phillips, 1993).
Unpredictable Markets
External markets for NTFPs tend to be unpredictable, operating on boom-bust cycles, with synthetics
substituting for natural products once an economy of scale is achieved (Padoch, 1992; Richards,
1993; Sizer, 1992). For example, during the early part of this century, Brazil exported 40 different
vegetable oils from the Amazon. The spread of electricity (and so decreased reliance on candles) and
extensive cultivation of corn and soybeans (which became the most popular vegetable oils
internationally) resulted in the decline of markets for these oils (Clay and Clement, 1993). But today,
there exists an increasing global market for vegetable oils, especially exotic, on the part ofcompanies
looking for environmentally-sound substitutes for plantation-grown palm oil. Chicle (used in chewing
gum) and tagua (used to make buttons) were both displaced by synthetic substitutes, but have recently
regained popularity through expanded marketing ventures in the United States (Reining and
Heinzman, 1992; Ziffer, 1992).
By maintaining a diversity of products in the extractive economy, rather than depending upon a few,
the potential impacts of individual product price fluctuations on the value of the forests for all NTFPs
can be minimized (Grimes et al., 1993; Clay, 1992; Clay and Clement, 1993). Markets for a single
NTFP species can also be diversified. For example, Brazil nut (Bertholletia excelsa) can be used as
nuts, in ice cream, baked goods, candy, oil, and as a flour (Clay and Clement, 1993).
It is important to note, however, that the bulk of NTFPs are traded on local or domestic markets.
While some of these markets might decline or disappear over time, either because the product is an
"inferior good" that drops out of consumption patterns as incomes rise, or because of competition
from factory-made alternatives, much of this trade is in products which enjoy stable or growing
markets (Arnold, pers. comm., 1994).
Adding Value Locally to NTFPs
Adding value to products destined for markets can be an important way to increase benefits for local
forest residents. Because adding value to forest products involves the combined efforts of collectors,
producers and marketers that do not usually work together, these efforts can be plagued by the
politics of ownership and control over infrastructure and processing facilities (Clay and Clement,
1993; Clay, 1992). The quality of products produced through local processing must be comparable
with that produced elsewhere, or these products will not sell on the open market.
Expanding the Markets Overseas
Wild plants and animals are subject to a management "Catch 22": if their economic utility is
overlooked or ignored, or if their use is in competition with another form of land use, they may
suffer from habitat destruction; if, however, their economic utility is evident, they are likely to be
over-exploited (Prescott-Allen, 1982). In building up markets for NTFPs located in a forest, a number
of international marketers of NTFPs and researchers suggest that one should begin with existing
products, rather than attempt to develop new ones, ideally replacing an existing commodity with
something superior or cheaper, or, in some cases, supplying unfilled demand (FAO, 1991; Gentry,
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1992; Ziffer, 1992; Clay, 1992). These should be those products with the highest market price, the
most reliable supply, and the greatest potential for future market expansion (Peters, 1993).
"Green" markets in developed countries for sustainably-produced NTFPs appear to be significant and
growing. For example, in 1991 39% of the American public considered themselves environmentalists
and 50% said that they would select a product for purchase based on environmental concerns (Dixon
et al., 1991; Clay, 1992).
The Over-Exploitation of Forest Products
Expanding production to enter new markets, or fill increased demand in existing markets, can result
in production problems. There exists a lag time between increased demand and adequate supplies,
as producers attempt to develop systems that will supply the quantity and quality of the product
desired (FAO, 1991). The harvesting of forest products for subsistence or small-scale trade locally
is usually based on traditional systems of forest management which have, through trial and error over
many years, developed sustainable methods ofextraction. When demand increases, however, existing
harvesting methods usually will not suffice; additionally, collectors from outside the area will enter
the forest to harvest valuable products 12 (Padoch, 1992; Cunningham, 1991; Vasquez and Gentry,
1989; Falconer, 1990; Godoy et al., 1992). Vasquez and Gentry (1989) describe this as the "critical
behavioral bottleneck" in the process of conversion from local consumption to commercial
exploitation.
Traditional resource management usually involves inadvertent (taboos, religious, seasonal and social
restrictions on gathering and the nature of equipment used) and at times direct management of
resources if harvesting practices appear to create shortages in a resource of value to society or the
socio-political nature of society depends upon it (Cunningham, 1991; Davies and Richards, 1991;
lain, 1992). When large demand for a forest resource is created, harvesting practices often change
in communities that have entered the cash economy, suffer from increasing unemployment, or have
undergone cultural change 13 (Cunningham, 1991; Vasquez and Gentry, 1989). Protecting these
resources by establishing laws or policing them will not, however, protect them from exploitation (De
long and Mendelssohn, 1992; Peluso, 1992).
Transportation
The costs of transportation and the perishability of a forest product determines how far away products
will be harvested 14 (De long and Mendelssohn, 1992). NTFPs tend to be difficult to ship due to
12 For example, pau rosa (Aniba roseadora) is currently over-harvested to the point of elimination in the Amazon,
but could 'be replanted and sustainably managed. Copaiba oil (Copaifera multijuga) can easily be harvested by drilling
a hole with a brace and bit and tamping it, but is more often destructively harvested by cutting a hole with an axe.
13 For example, Wamulwange (1993) reports from Zambia: "In the past the traditional government would charge a
sum of five pounds for cutting timber without a license. One pound for cutting a fruit tree, but no charge for the
collection of fIrewood. Some areas were declared as forest reserves where a culprit would be charged the sum of ten
pounds for grazing, ten pounds for cutting and one pound for trespassing. People are not respecting these laws anymore."
14 Assai is found in nearly monocrop stands, both naturally occurring and created, near the mouth ofthe Amazon and
in varying densities along the river all the way to Bolivia. In 1990, the market for assai fruit, which was entirely domestic,
was nearly US $100,000,000. The main market for the fruit is in Belem, where as many as 50,000 I of unprocessed fruit
are sold daily. Harvesters in the area earn as much as US$10 to $US15 per hour. The Belem market can only be supplied
by fruit that is no further than a single night's boat trip away because after 24 hours it spoils. Within this area, then, assai
is very valuable. Outside of this radius, assai stands are decimated and sold for palm heart (Bovi and de Castro in: Clay
and Clement, 1993; Clay and Clement, 1993).

spoilage, although many have a much higher kilogram value than even the most expensive timber
(Clay and Clement, 1993; Richards, 1993).
Box 1: Lesser Known Timber Species
In addition to non-timber forest products, the use of a larger number of timber species in a natural
forest can increase yield/unit area, and could improve the economic outlook of natural forest
management. Generally, only 10-50 of the thousands of tropical tree species have been commercially
exploited, but high-grading has depleted stocks of premium timbers and deforestation has made timber
scarce (Hartshorn, 1990). As a result, efforts have been undertaken to promote the lesser known species
(LKS) of high-diversity tropical forests. Although if done to excess, this could result in the depletion of
nutrients in forest ecosystems, it is generally accepted that - if done sustainably - the harvest of LKS
would make better use of the forest resource, and less forest could be harvested to meet demands for
timber. In order for LKS to succeed, the conservatism within the timber trade must be overcome,
species must be marketed 10 consumers, infonnation on the wood properties of these species must be
made available, and consistent supplies ensured (Jonson and Lindgren, 1990).
In general, the more distant a timber consumer market is from its timber supply area, the more selective
it is about the number of wood species it consumes. In part, this is due to the costs of transJX>rt. Local
markets in the Amazon, for example, appear to be the least discriminating, with national markets
accepting a large percentage less and international markets even fewer (Browder, 1986; Feamside,
1990). Browder found, for example, that of the 7 principle Brazilian Amazon woods exported to the
United States in 1982, mahogany accounted for 84%.
In Queensland only one species, Red cedar (Toona Australis) was used by the early settlers, 10 species
were used by 1930, and over 100 species by 1945. Leslie (1987) suggests that this is a function of the
growing scarcity of prime species and thus the greater acceptance of alternatives and of small-sized
species.
In Malaysia, only 30 timber species are harvested for export in significant quantities (JoOOs, A.D.,
1992). In the Brazilian Amazon, Uhl et al. (1989) reported that 222 trees of only 30 species were
extracted from a 52 ha forest tract in Para, although the total number of timber species in the Amazon
is estimated by Martini et al. (1993) at 335, and local mills now use approximately 140 species (as
opposed to 6 species 40 years ago). Nair (1991) found that for an area in India, 30 species were listed
for felling, but in fact a disproportionately large number belonging to 3 or 4 species were removed for
specific ends.
Martins (1992) reports that the promotion of lesser-known or non-traditional wood species in Honduras
looked promising. Because the traditional mahogany and Spanish cedar species are increasingly scarce,
room in the market has been created for the LKS species. Promotional activities, such as an exhibit of
fInished furniture pieces of high quality made entirely of LKS, have proved to be a success (Martins,
CIDA, pers. comm., 1992).
9

10
Box 2: The Economic Valuation of Non-Timber Forest Products
The harvest of medicinal plants for local use in Belize was estimated to have a net present value (NPV)
of $726/ha in 30 year old forest and $3,327/ha in 50 year old forest. The plots in which medicinals
were collected also contained other valuable income-generating NTFPs, like chicIe (Manilkara zapota)
and allspice (Pimenta dioica), which were not included in these values. This compares favourably with
alternative land uses. Estimates of the value of intensive agriculture in the Brazilian rainforest are
$339/ha, and in Guatemalan forests $288/ha. The most successful pine plantations proposed for the
tropics yield only $3,184/ha (Balick and Mendelssohn, 1992).
Peters et al. (1992) similarly demonstrated the economic superiority of NTFPs using standard costbenefit
analysis for a forest in Peru. The NPV of sustainable fruit and latex harvests was estimated at
$6,330/ha, and of total NTFPs at $6,820. The standing volume of merchantable timber in this tract of
forest was 93.8 m 3 jha if liquidated in one felling, and a net revenue of $1,000 would result upon
delivery to the sawmill. A logging operation of this intensity, however, would so damage the residual
stand that future revenues from the site would drastically reduce or eliminate future harvests of NTFPs.
The net financial gains from timber extraction would be reduced to zero if as few as 18 fruit trees were
damaged by logging. Periodic selective cuttings of the 60 commercial species at the site, however,
would produce volumes of 30 m 3 /ha every twenty years, which would produce net revenues of about
$310 at each cutting cycle, or an NPV of $490 (peters et al., 1989).
In Ecuador, Grimes et al. (1993) found that the three plots in their study produced NPVs for NTFPs of
$2939/ha, $2721/ha, and $1257/ha (with upland forest providing the largest returns). Timber resources
calculated on a 40 year rotation length produced an NPV of $188/ha. Cattle ranching has a NPV of $57
in the same area. Markets for NTFPs appeared to be expanding locally, regionally, and nationally. The
values calculated for NTFPs do not include medicinal herbs or shrubs, flowers, wildlife, tourism or the
wide range of environmental services provided by intact forests, all of which would greatly enhance the
forest's economic value. For example, one guanta (Paca agouti), a forest rodent, sells for $20.69 in the
local market, and decorative butterflies sell to tourists for a similar price. Selective, low-impact
harvesting of timber species would additionally add to the NPV for the forest area (Grimes et al.,
1993).
The results of these valuations of non-timber products will vary depending upon the biological and
economic diversity of study sites, temporal changes in market prices, production levels and harvest
intensities, and the methods and reporting procedure employed by the researchers15. Although these
studies usefully demonstrate the previously ignored "invisible" economic value of NTFPs, the
methodology employed is still in development and there remain a number of doubts as to the practical
relevancy of the results. For example, many of these valuations do not take into consideration the
impact of greatly increased supplies on the market and prices, transport costs from more remote areas,
the non-sustainable nature of some harvesting, the shortcomings of basing values on returns to land
rather than labour (which is the scarce factor), the assumption that local populations would base
decisions on discounted future values, and the great importance of institutional factors (such as insecure
land tenure) that influence local decisions about the use of forest resources (Amold, pers. comm., 1994;
Godoy and Lubowski, 1992; Pinedo-Vasquez et al., 1992).
IS Godoy and Lubowski (1992) suggest that because many of these studies measure costs, quantities extracted, and
prices in different ways, the results cannot be directly compared with each other; researchers, therefore, must pay more
attention to their methods so that future studies can produce genemlizable results (Godoy and Lubowski, 1992).

12
Because of the unpredictable nature of markets for non-timber products and the irregularity of yields
from these species, it is generally best to manage forests for a wide range of species and potential
products 18 •
When selecting species for natural forest management, Peters (1993) suggests that, given a group of
species with similar economic profiles, ecological criteria should be incorporated to assess the
potential for sustained-yield management: the life cycle characteristics, the multiplicity of uses and
types of resources produced, the abundance in different forest types, and the size-class distribution
of populations.
Species that are annually fruiting, hermaphroditic, and pollinated by a common, generalist vector are
much easier to work with than an unpredictably fruiting, dioecious species requiring specialized
animal vectors for pollination and seed dispersal 19 • Primary forest species adapted for growth and
regeneration under a closed canopy, such as Carapa guianensis, Copaijera multijuga, Theobroma
grandijlorum, and Coumarouna odorata in the Amazon will, in most cases, be preferable to fastgrowing
early pioneers which require large gaps for seedling establishment (Peters, 1993; Smith et
al., 1992). Following logging, however, larger-sized gaps can be filled with useful pioneer species,
such as Croton cajucara in the Amazon or Rauvolfia vomitoria and Musanga species in West
Africa 20 •
The abundance, or current density and distribution, of a species will also affect the ease with which
they can be managed, their yield per unit area, and the likelihood that they can be sustainably
managed (Peters, 1993; Gentry, 1992; Reining and Heinzman, 1992; Reining et al., 1992;
18 For example, a good year of Brazil nut harvest is usually followed by a bad one, as the tree uses most of its
accumulated reserves and takes more than a year to accumulate more. Fruiting is said to be heavy in alternate years only
(Clay and Clement, 1993). The quantity of copaiba (Copaijera multijuga) drawn from each tree depends upon the
botanical species of the tree, its age, the lapse of time since the previous tapping and upon season.
19 The Brazil nut (Bertholletia excelsa), for example, has well-established and lucrative markets, but is cross pollinated
by non-social or semi-social large bees with enough strength to pry open flowers, and has seeds which are dispersed by
agoutis (Dasyprocta aguti) and squirrels (Sciureus spp.), which appear to be the only species capable of gnawing through
the extremely woody pericarp (Mori, 1992).
A lack of Brazil nut regeneration on the forest floor has been observed throughout Amazonian, but has not been
adequately explained. It is possible that, because the large capsule fruits are so easy to find, gatherers do not leave enough
seed on the forest floor to be dispersed by agoutis and develop into seedlings. In addition, lack of regeneration could be
due to reduced populations of the major dispersal agent (agoutis) through hunting, low fertilization/germination rates, seed
vulnerability to fungus, seedling dependence on large openings, the burning beneath adult trees to facilitate collection and
nut production, or a lack of pollinators in cases where trees are not in proximity to the natural forest on which the bees
depend (Nepstad et al., 1993; Mori, 1992; Smith et al., 1992).
20 Rauvolfia species have yielded reserpine, the starting point for traditional and phannaceutical treaunents for
hypertension. The crushed root, seeds and leaves are used locally in a variety of traditional remedies. The ashes ofburned
Musanga spp. are used as a salt substitute, its wood for a variety of construction purposes, and various plant parts are
used in traditional medicines (Abbiw, 1990).

Cunningham, 1992)21. Clearly, rare species are in more danger from the essentially random damage
inflicted by logging operations than common species are (lohns, A.D., 1992); similarly, unsustainable
harvesting of plant parts or entire trees for non-timber forest products will endanger populations of
rare individuals more than the common. Although high-density populations of species are easier to
manage than low, the vast majority of tropical species occur at low densities (Sayer, 1991; Peters,
1993; Peters et al., 1989). Additionally, most traditional management systems promote and depend
upon a wide-range of forest vegetational zones and products, and so are directly linked to high
species diversity. (Nair, 1991; Salick, 1992; Toledo, 1992; Alcorn, 1990; Phillips, 1989)22. In
economic tenns, the harvest of a multiplicity of non-timber forest products is preferable to the harvest
of a few because it minimizes the potential impacts of individual product price fluctuations (Grimes
et al., 1993).
In the Amazon, most of the major non-timber product species occur at extremely low densities, but
have wide geographic distributions. Carapa guianensis, Hymenaea courbaril, Platonia insignis,
Dipteryx odorata, and Caryocar villosum average less than one tree!hectare (although densities of4-6
trees!ha have been reported for Carapa in northeast Costa Rica). Copaijera multijuga averages just
over 1 tree/ha (Clay and Clement, 1993; lonson and Lindgren, 1990). Theobroma grandiflorum can
reach 14 trees!ha and Bertholletia excelsa as many as 20 trees!ha, but this type of abundance results
most likely from Amerindian intervention 23 •
Many timber species also provide non-timber products, which can generate revenue throughout the
economically "unproductive" building phase following logging operations (Salick, 1992; Reining and
Heinzman, 1992; Malhotra et al., 1991)24. Martini et al. (1989) found that of the 335 timber species
utilized in the Brazilian Amazon, one-third were also valued for their fruits, medicinal properties,
and/or gums and resins. The bulk of these have "high" (but not greater than $40/m 3 ) wood values and
are under "high" logging pressure (Martini et aI., 1993). In some cases, such as rosewood (Aniba
duckei), non-timber values exceed timber values (Clay and Clement, 1993). The physiological tradeoffs
of harvesting multiple resources from a single tree should be assessed prior to initiating such a
21 In the Maya Biosphere Reserve in Peten Guatemala, three important NlFPs occur in remarkably high densities:
xate (Chamaedorea spp.), the leaves of which are exported to the United States and Europe, where they serve as a green
backdrop for cut flower arrangements; chicle (Manilkara zapota), a natural latex used in the manufacture of chewing gum
bases; and allspice, the berry of Pimienta dioica used as a condiment, to preserve fish, and as a flavouring and curing
agent in processed meats and bakery products. It is likely that this results from Mayan forest gardens and management.
As Reining and Heinzman (1992) described it: "it is as if this is a pre-managed forest". High density and numbers of
these NlFPs and dozens of secondary timbers, thatching palms, construction materials and medicinal plants facilitate
sustainable management in this area (Reining and Heinzman, 1992; Reining et al., 1992).
22 An ethnobotanical study of eight indigenous groups in the tropical moist zones of Mexico showed that 1,380 plant
species were identified as having one or more uses. Of these, 465 are primary forest species, 712 are secondary forest
species (153 of the two preceding figures are species found in both), and 356 are species without ecological specification
of habitat (Toledo, 1992).
23 Forests dominated by stands of Brazil nut trees are called castanhais. They occur over an area of 8000 km 2 in the
Amazon Basin (Balee, 1989).
1A For example, in Southwest Bengal the pioneer species Diospyrros melnoxylon is harvested to provide a wrapper
for Indian cheroots (bedi) in degraded forest prior 10 shading out by the canopy of timber species (Shorea robusta).
Enrichment planting of mushrooms and medicinal also contributed significantly to economic returns after canopy closure
(Malhorta, et al., 1991).
13

14
program; for example, tapping oleo-resin or latex will undoubtedly have some effect on the
production of fruit (Peters, 1993).
For the vast majority of non-timber forest species, we have little data on tree density, productivity
and population structure. Many species are as yet undefined 25 • In order for sustained-yield of these
species to be possible, however, we must know: the location and identity of the resource; the
resource's history of exploitation; the total number of harvestable trees per hectare; the current
population structure or size-class distribution of the species and the quality of regeneration; the
productive capacity of the species being exploited, and the relationship between tree size, site, and
productivity; and the maximum amount that can be exploited - i.e. the sustainable harvesr 6 •
Plant Parts Used In Non-Timber Forest Products
The sustainable harvesting of non-timber forest products depends in large part on the part of the plant
that is used (Cunningham, 1991; 1992). The bulk of NTFPs can be grouped into three basic
categories based on the type of plant tissue or compound actually exploited: reproductive propagules
(fruit, nut/seed, oilseed); plant exudates (latex, resin, and floral nectar); and vegetative structures
(stem, leaf, root bark, and apical bud) (Peters, 1993).
Reproductive Propagules
The harvest of fruits, nuts and oilseeds removes plant embryos from the site, and hence reduces the
total number of seedlings that can potentially be recruited into the tree population under exploitation,
alters populations structure, genetic variability, and can impact the foraging behaviour of local animal
populations 27 • Low density populations which display an obligate relationship with a specific
pollinator or seed disperser will have a much lower sustainable yield of fruit, and will be more prone
25 For example, the most important construction timber of the Iquitos, Peru area (72-74% of the wood used for general
construction came from this species) was recently collected by botanists and found to be a species new to science. "Boa
caspill", the main construction timber at Jenaro Herrera on the Rio Ucayali, turned out to be an undescribed species of
Havloclathra, so distinctive it was frrst suspected to be a new genus (Gentry, 1992).
26 The most immediate and cost-effective way of doing this is by monitoring (in permanent sample plots) the
population impact of exploitation and sequentially adjusting harvesting levels over time to obtain a sustainable yield; this
method is known as successive approximation. In practice, achieving sustained yield through successive approximation
will probably involve a considerable number of harvest adjustments. There is frequently a tag time in the demographic
response ofa population to perturbations, such as logging or high-intensity harvest, and after several cycles of apparently
stable results from PSPs, populations may exhibit drastic fluctuations in seedling and sapling densities. Sustainable
harvesting levels can thus be achieved through a process of reciprocal feedback and "fine-tuning" (peters, 1993; Malhorta
et al., 1991). Frequently, too, local peoples have determined sustainable levels of harvest from trial and error, and
ethnobotanical information can reveal a substantial amount of information concerning the sustainable productivity of
tropical forest resources (De long and Mendelssohn, 1992).
27 If a tree population produces 1,000 seeds and 95% of the new seedlings produced from these seeds die during the
frrst year, the population still has recruited 50 new progeny. If, on the other hand, intensive fruit harvesting removes all
but 100 of these seeds from the site prior to germination, the maximum number of seedlings that can be recruited into
the population is reduced to only 5. This ten-fold shortfall in recruitment rate can cause serious changes in the structure
of the population (peters, 1993).

to over-exploitation than species with abundant regeneration, not prone to extreme post-dispersal seed
predation, that are pollinated and dispersed by either "generalist" animals or abiotic factors (Peters,
1993)28.
In some cases, poor harvesting practices can lead to drastic species decline not associated directly
with removal of the reproductive propagules. For example, trees are often felled to collect fruits. In
the Peruvian Amazon, female trees of the dioecious aguaje palm (Mauritia fleusosa) are felled by
commercial collectors and after a few such "harvests" the forest is left with a preponderance of
barren male trees (Peters, 1993).
Plant Exudate
When properly conducted, the tapping of latex, resins and gums does not disturb the forest canopy,
kill the exploited tree or remove its seed from the site (Peters, 1993). In theory, this activity can
easily be sustainable, but in practice poor harvesting techniques plague these products, as well.
Copaiba (Copaifera multijuga), for example, can be tapped through its lifespan if a brace and bit are
used, and holes are filled following tapping. In practice, however, axes are often used to create holes
and the wounds created do not heal (Clay and Clement, 1993). Additionally, many species, such as
the Amazonian Couma macrocarpa, which produces valuable fruits and latex, are felled to harvest
plant exudate that could be easily tapped 29 (Peters, 1993). It is also likely that repeated tapping, for
example of Hevea brasiliensis, reduces vegetative growth and total fruit production (Peters, 1993).
Vegetative Structures
Although the origin and use of plant products from root, stems, leaves, barks, or apical buds, is very
different, their harvest produces a similar ecological impact. The plant species will either be killed
during harvest or will survive and regenerate the vegetative structures removed (Peters, 1993).
Stems
Rattan harvest in Southeast Asia is an example of particularly destructive harvesting of commercial
quantities of stem fibre. Rattan is harvested by cutting the plant at the base and then pulling the
(often more than 100 m long) stems and leaves out of the forest canopy. Large-caned, single
stemmed rattan, such as Calamus manan, do not resprout after cutting, so harvesting kills these
individuals. Small-caned, multi-stemmed individuals, such as C. caesius and C. trachycoIus, can
eventually resprout after harvesting, and individual stems can be cut from the clumped vegetation
every 2-3 years after an initial 8-10 years of growth (de Beer and McDermott, 1989; Peters, 1993).
Over-exploitation of both small- and large-caned stems, including cutting them too close to the
28 The illipe nut of Shorea species in Southeast Asia, for example, produces a high quality oil used in the cosmetic
industry and as a substitute for cocoa to harden chocolate. But many of the most important Shorea species providing illipe
nut are fruit masting, and set flowers every five years, so productivity is low (De Jong and Mendelssohn, 1992; Dixon
et al., 1991).
29 Gaharu wood (Aquilaria spp.) is an extremely valuable aromatic resin resulting from infections of trees by unknown
pathogens. Aquilaria spp. are found in the primary forests of Southeast Asia. The collection of gaharu usually involves
felling the trees, which resprout weakly, if at all. Because there are no external signs to indicate whether a tree contains
the valuable exudate, collectors frequently fell every Aquilaria tree they find (although the Penan are successful at
identifying the desirable trees without felling). Uncontrolled exploitation and wasteful felling in search of gaharu has led
o its rapid decline (Padoch et al., 1992; Peters, 1993; Zemer, 1993; Stockdale, pers. comm., 1993).
15

16
ground and at too young an age, coupled with increased logging pressures on the forests in which
the vast majority of commercial species are harvested, have led to increasing scarcity of valuable
rattan species (Peters, 1993; Sayer, 1991; De Jong and Mendelssohn, 1992)30.
The harvest of chewsticks, made from the stems of primarily Garcinia epunctata and Garcinia afzelii,
provides the main means of dental care for 90% of the population in southern Ghana. Despite the
increasing popularity of Western-style toothbrushes, toothpaste is hard to come by, and demand for
chewsticks continues to rise (Falconer, 1992; Cunningham, 1992). Trees are cut from the forests,
usually by groups of gatherers who come out from the cities specifically for this purpose, and the
harvest is then taken back by truck to the urban markets. Falconer (1992) found that 2,000-6500 trees
a month are harvested in the Kumasi region alone, and that almost every gatherer claims that these
species are becoming increasingly scarce in the forest.
Leaves
The harvesting of leaf fibres may have a negligible effect on the structure and abundance of plant
populations being exploited if: individual plants are not killed in the process, a few healthy leaves
are left on each plant to photosynthesize, reproductive structures and meristems are not damaged, and
sufficient time is allowed between successive harvests for the plant to produce new leaves (Peters,
1993). Many traditional medicines and internationally-traded herbal medicines come from leaves 31 •
In many cases, the extent of demand for leaves has resulted in diminished populations, due to the
factors described above. Leaves stripped from the Amazonian Pilocarpus spp., for example, provide
the active compound pilocarpine, which is used in the pharmaceutical treatment of glaucoma 32 • In
1989, over 1300 tons of dried plant material were exported to the United States alone (Elisabetsky,
1991). Due to scarcity and the desire to control supply, the pharmaceutical company E. Merck of
Germany has spent ten years attempting to cultivate Pilocarpus spp. It has had a difficult time doing
so, as leaves with adequate quantities of the desired chemical compounds have been difficult to
produce in plantation (Sheldon et al., 1993). The secondary compounds useful in medicines are often
not produced when plants are grown outside of the difficult and competitive atmosphere of their
natural environment. As a result, wild sources will continue to be an important source of raw material
for even the most "high-tech" of medicines.
Roots and Bark
The collection of roots and bark usually kills or fatally weakens the exploited tree species,
particularly with high-intensity harvests (Peters, 1993). Bark can be renewably harvested if trees are
30 Stockdale (pers. comm., 1993) reports that traditional management and harvesting practices in East Kalimantan have
often been overlooked by outside collectors and are being dismissed by some of the younger members of the community.
For example, the traditional practice of cutting the stem 1 m from the ground and then bending the tip of the stump back
into the earth to prevent fungal infection spreading from the stump into the rest of the clump, is perceived as wasteful
of valuable cane.
31 For example, sacaca (Croton cajuacara) leaves, dried and made into teas or sold in gelatin capsules, have become
"the most" fashionable medicinal plant in Belem these days. It is used to treat diabetes, diarrhoea, and to lower
cholesterol. Because it is a weedy pioneer species, its survival will probably not be severely affected even by the rapidly
increased demand that has recently occurred (Venturieiri and Ribeiro in: Clay and Clement, 1993).
32 In 1989, the estimated sales of pilocarpine in the United States alone reached US$28,000,000 (Elisabetsky, 1991).

not girdled, but management strategies of this kind are often disregarded, or succumb to enonnous
market demand for the species 33 • The harvest of roots will kill the individual plant, but management
of these species, including regulating off-take, can minimize the impact on populations 34 • Both barks
and roots can be harvested from multi-purpose trees felled for timber, prior to or post-harvesting. The
bark of Pau d'arco (Tabebuia serratifolia), for example, is harvested for use in medicines used
regionally and internationally, prior to logging operations in Brazil.
Apical Buds
Palm hearts are the most important and well-known example of apical bud use. In a single-stemmed
palm species, harvesting the "heart", or apical meristem, necessarily kills the tree. Euterpe precatoria,
for example, was widely harvested for a palm heart canning factory near Iquitos, Peru, which was
subsequently forced to close due to scarcity of raw materials. The multi-stemmed growth fonn of E.
oleracea in the Amazon enables the species to sprout back after cutting, and collectors in the eastern
Amazon have taken advantage of this to manage for a sustained-yield harvest (Peters, 1993).
Wildlife as a Non-Timber Forest Product
Wild game is often overlooked as an important non-timber forest product, but is one of the most
marketable and higher value forest products. The rural population's dependence on wild meat for
subsistence is also extremely important. For the hunter and his family, hunting is free or very cheap
in monetary tenns. This is important because large sectors of the rural population still have limited
access to cash with which to buy substitutes (Caldecott, 1988).
Caldecott (1988) calculated that about half the minimum protein supply in Sarawak is derived from
fresh meat, almost 60% from the wild, including fish. Meat also provides a "buffer" in times when
other crops are inadequate 35 • Hunting constitutes the major source of yearly revenue for the families
in the northern Congo studied by Wilkie et al., (1991). Many families reported that without revenue
obtained from hunting, they would be unable to buy cooking utensils, clothing, medicine, and
educational materials for children. Logging operations in this area had directly and indirectly
contributed to the depletion of local stocks of wildlife (Wilkie et al., 1991).
33 The bark from the Cameroonian species Pygeum ajricanus, for example, is used to treat urinary problems associated
with enlarged prostate glands. By removing bark from opposite quarters every 5 years, and stripping up to 20 m above
ground, the bark of P. africanus can probably be sustainably harvested, as it appears to be very resilient to bark removal.
In practice, however, trees are often felled to collect the bark, or entire trees are stripped. By 1989, most of the forests
where the bark was sOUTced in Cameroon were depleted of P. africanus (Cunningham, 1993; Sheldon et al., 1993).
34 The root of the slow growing understorey herb ipecac (Cephaelis ipecacuanha) has long been used traditionally
to treat dysentery and as an expectorant. The scale of current international demand for ipecac (as an ingredient in
expectorants and in a treatment for amoebic dysentery) has led to over-harvesting in the wild and severe reductions in
local populations (Sheldon et al., 1993; Husain, 1992). In Nicaragua, local communities successfully managed the
extraction of ipecac, which is one of the most important NTFPs in the region, by planting beds below the forest
overstorey (Salick, 1992).
35 The contribution of wild meat to human nutrition in the interior is illustrated by rations for pupils at boarding
schools: 203 tonnes of meat and fish were consumed at 63 schools in 1984-85; the largest single component was wild
pig meat at 32%, with other wild meat contributing about 7%, fish about 18% and domestic pork, beef and chicken 13­
16% each. In 1984 the estimated traffic in wild pig and deer meat exceeded $4,000,000 in the Rajang basin.
17

18
Wild game is also one of the most popular foods in Ghana. It is in equally high demand in urban and
rural areas. Forests and fallow fields provide the habitat for many commonly consumed wildlife
species. Forest-dependent animals are particularly important in humid West Africa because substitutes
are often not available. Tsetse flies are endemic to this area and make cattle production difficult.
Wild animals contribute between 20-90% of the total animal protein consumed (Falconer, 1992;
1990). A.G. Davies (1987) similarly found that in the Gola Forest Reserve in Sierra Leone,
unfavourable conditions for cattle and other livestock had lead to a traditional reliance on fish and
bushmeat as sources of animal protein. While different communities have different preferences, for
example Moslems disdain monkey meat, hunting of wildlife in this area is a major activity.
In addition to the economic and nutritional importance of wildlife must be added the role of hunting
in many indigenous cultures. Hunting is central to the culture of the Penan, many of whom are still
hunter gatherers. It is also integral to shifting cultivation and its associated cultures. As Caldecott
(1988) said, for centuries, "to be a Dayak was to be a shifting-cultivator, was to be a hunter".
Redford (1991) notes that in the Neotropics many indigenous communities associate hunting with
social status and power. In the sharing of game with the rest of the community, the hunter builds
debts, acquires allegiances and contributes to social cohesiveness. Shortages in meat have been known
to create social tension and even village fission, and hunters in some cases must engage in wage
labour to purchase canned meat and fresh fish, with repercussions in the community cohesiveness.
Decreases in game yields or prohibitions on hunting can have repercussions well beyond the strictly
nutritional (Redford, 1991). (See below for a discussion of the "Impact of Natural Forest Management
on Wildlife").
v. The Ecological Underpinnings of Natural Forest Management
The sustainable harvest of timbers from tropical forests is dependent upon a variety of factors and
complex ecological relationships, most of which remain largely unknown. Despite ignorance of the
intricacies of tropical forest ecosystems, general ecological principles have and continue to guide the
design of natural forest management objectives and the harvesting operations and silvicultural systems
they employ. These, in turn, influence the diversity of species and forest structure, and the harvest
of non-timber forest products that rely on this diversity.
Forest management - whether manifested in logging operations or silvicultural treatments - creates
disturbances. It is in the extent that these disturbances mimic the size, duration and frequency of
naturally-occurring disturbance that ecological sustainability is achieved. Tropical forests are dynamic
- not homogenous and static - mosaics of young, middle-aged and mature patches in different stages
of regeneration (Putz and Brokaw, 1989; Uhl et al., 1990; Swaine, 1986)36. The concept of a steadystate
"climax" forest has been questioned by many who feel that it does not reflect the dynamic
nature of tropical moist forests, and some suggest that in fact forest virginity is "relative" (Hartshorn,
36 Whitmore defmes three growth cycle phases in tropical forests: the gap phase, which is the opening of the canopy;
the building phase, which consists of young trees, mostly shade-intolerant, growing rapidly to fIll the gap and attain the
canopy; and the mature phase, formed by an intact canopy of large trees (Whitmore, 1991; Hartshorn, 1980).

1980; Niering, 1987)37. Not only have indigenous inhabitants long modified the forest environment,
but small-scale natural occurrences such as treefalls, and large-scale disasters such as hurricanes,
fires, landslides, and droughts, have created forests in a constant state of repair. Although a
directional change in floristics will not occur in a mature phase forest as a whole, the composition
at a given spot, from one tree to the next, will change. (Balee, 1989; Hartshorn, 1980; Whitmore,
1991; 1992; Brown, 1992). Hartshorn (1980) found that in mature La Selva forest in Costa Rica, the
turnover rate between two successive gaps occurring at the same spot in the forest was as high as
118 +/- 27 years. Uhl et al. (1990) found that 4-6% of the forest area in Amazonian Venezuela was
in a "gapped" condition at anyone time.
Fundamental to most harvesting operations and silvicultural systems is the importance ofregeneration
in the gaps created by logging, and forest management systems have been developed to explicitly
stimulate the growth of the pool of desirable species 38 . Gap size is manipulated during logging
operations to match the growth characteristics of commercial species and silvicultural treatments are
applied to release the advanced regeneration of desirable individuals and suppress the
"undesirable"39 (Uhl et al., 1990; John, A.D., 1992, Wyatt-Smith, 1987). "Sustainable" forest
management generally tries to mimic natural disturbances, and utilizes ecological succession and the
mechanisms and factors that drive the processes of species change, population change and
replacement through time to promote the regeneration of commercial species (Gomez-Pompa and
Burley, 1991; Brown, 1992; Lawton, 1984). Interspecific competition for the establishment of sites
has resulted in adaptive compromises in regenerative strategies, which results in varying competitive
success of species in gaps. Differential species response will depend on the size of gaps, the timing
of gap occurrence, the proximity and dispersal of seeds, growth rates, architectural construction that
facilitates competition for light, nutrient requirements relative to competitors, nutrients available at
the sight, water use and efficiency, and resistance to seed and seedling predation, pathogens and the
increased herbivory associated with gaps (Denslow, 1980; Wyatt-Smith, 1987; Bazzaz, 1991; Nepsted
et al., 1991; Hartshorn, 1980; Brown, 1992).
37 Niering (1987) quotes Egler's 1947 statement that "the Climax and God have certain things in common for certain
botanical atheists. To paraphrase Julian Huxley, the writer does not believe in the climax, because he thinks the idea has
ceased to be a useful hypothesis. 1t
38 The process of topling a tree, the fallen tree itself, together with the resultant hole in the canopy and accumulated
debris on the forest floor is known as chablis or gap formation (Hendrison, 1990).
39 The immigration of species and progress of succession can occur through a number of regeneration pathways:
1) Seedlings and saplings of climax species present on the forest floor with little or no real growth toward adult size
are stimulated by the new microenvironment resulting from canopy opening. UhI et al. (1990) found that in the
Amazon, this advanced regeneration played a dominant role in tree fall gap formation and that four years after gap
formation, composed 950/0 of the species> 1 m tall (Uhl et al., 1990; Bazzaz, 1991; Gomez-Pompa and Burley,
1991).
2) Sprouting from stem bases or roots following the destruction of above-ground plant parts also plays a major role
in gap-phase regeneration (UhI et al., 1990; Irvine, 1989). Putz and Brokaw (1989) found in Panama that sprouted
trees contributed more significantly to canopy closure in small gaps than in large, and that they initially grow faster
than seedlings of the same species.
3) Recolonization by the germination of pioneer species seed buried in soil seed bank, but not growing as seedlings
or adult trees in the immediate area (Gomez-Pompa and Burley, 1991; Uhl et al., 1990).
4) The arrival of seeds, which might fall from surrounding trees, or are dispersed from distant trees by wind, birds,
bats, rodents and other mammals (UhI et al., 1990).
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VI. Harvesting Operations in Managed Natural Forest
The manner in which logging operations are conducted directly influences the present and future
harvest of both timber and non-timber products from the forest. The extent of logging damage
associated with most operations in the tropics results not only in the drastic decline of local species
diversity and forest structural diversity, but also unfavourable rates of basal area growth of
commercial species through the destruction of seedlings, adolescent trees and soil surface and
drainage pattems 40 (Whitmore, 1991; John, A.D., 1992; Dykstra and Heinrich, 1992; Dawkins,
1958). Destructive logging operations can also result in increased fire hazards, lowland flooding, and
decreased marine and coral reef productivity.
Nepstad et al. (1991) found in the eastern Amazon that to harvest 1.6% of the trees in a forest, 12%
of the trees with a dbh > 10 cm lost their crowns, 11 % were uprooted and 3% suffered substantial
bark scarring. Uhl (1989) cites similar figures for residual stands in eastern Amazonian: 11%
uprooted by bulldozers for roads, 12% crushed in felling, and 3% with excessive bark removal. In
their efforts to extract 52 m 3 /ha, or eight trees, logging operators destroyed 26% of those remaining.
Canopy cover (a summation of road area, felled tree area and log storage area) was reduced by half
(Uhl, 1989; Wilkie et al., 1992). In Malaysia, A.D. John (1988) found that for the removal of 30-50
m 3 /ha, or 3.3% of the trees, total canopy cover was reduced 50%.
Damage in selective harvesting systems is usually patchy due to varying population densities of
commercial species. This is particularly pronounced in the highly diverse neotropical and African
forests. In Malaysian dipterocarp forests, dominated by Dryobalanops aromatica or Shorea curtisii
species, 14-72 trees may be removed per ha. Amazon terre firme forests yield on average 3-5
trees/ha, and African forests can yield as few as 1.1 commercial trees/ha (John, A.D.; Uhl, 1989).
Logging has numerous and potentially severe impacts on the soil surface of forests. The removal of
humus and topsoil during logging operations can result in high rates of soil erosion and leaching,
particularly on slopes, and can produce high depositions of soil and debris on valley floors and flat
areas during the wet season (Uhl et al., 1981). Rutting and the disturbance of the soil surface can also
significantly disrupt the seed bank, seedlings, and superficial feeding roots critical to regeneration
(Whitmore, 1991; Hendrison, 1990). But perhaps the most significant factor in the growth of future
stands of timber and non-timber species on logged-over sites is soil compaction. Soil compaction
affects tree growth through reduced porosity resulting in decreased diffusion of gases, root
penetration, and the flow of water. The type and degree of soil compaction depends upon soil
characteristics such as texture, structure, field moisture content, and organic matter content, and on
the intensity of machinery traffic, its gross vehicle weight, steering system, and tire and track type
(Hendrison, 1990; Jonson and Lindgren, 1990). Soil recovery is a slow process. Hendrison (1990)
found in Suriname that skid trails used eight years previously were still maximally impacted. At Jarl,
in eastern Amazonian Brazil, the clearance of large forest areas for plantations by machine was
abandoned because trees grew so poorly on compacted soils (Whitmore, 1991).
40 Damage to the residual stand can take the form of direct damage, wounds which are vulnerable to pathogen attack,
water stress, the loss of symbiotic mycorrhizal infections, invasion by climbers due to excessive canopy opening, and
windthrow resulting from increased turbulence of the uneven canopy (John, A.D., 1992; UbI, 1989).

Although adequate information exists to implement efficient and ecologically-improved logging
systems, a number of economic and social factors have precluded its implementation. These include:
short-term objectives that result in cost minimization and profit maximization; government concession
agreements, incentives and payment schemes that do not stimulate sustained yield management; profit
margins which have been unreasonably high in the past and have concessionaires "spoiled" with
regards to expected returns; and the poor dissemination of knowledge from research to those
conducting logging operations (lonson and Lindgren, 1990; Dykstra and Heinrich, 1992). But
successful natural forest management depends on well-managed logging operations - as de Graaf and
Poels (1990) said, "the first priority is to domesticate the logger, whereupon it is possible to
domesticate the forest".
A sustainable logging operation will involve more than felling and extracting timber. Harvest
planning, technical supervision and post-harvest assessments that reflect concern about the biological
diversity, non-timber forest products and long-term health of an ecosystem are required components
of what Dykstra and Heinrich (1992) call "harvesting", as opposed to "logging", operations.
Harvesting operations should be based on silvicultural considerations, as the success of silvicultural
systems will in large part depend upon the preceding harvest. Wyatt-Smith (1987) describes timber
felling as the first major silvicultural operation of a natural regeneration system. The key elements
of a harvesting system are: harvest planning, forest roads, felling operations, skidding and yarding
operations, and post-harvest assessments (Dykstra and Heinrich, 1992; Jonson and Lindgren, 1990).
Harvest Planning
Harvest plans are based on inventories and the collection of information necessary to ensure
ecological sustainability and to plan transportation within the forest in a way that minimizes damage
to residual stands and the total area disturbed by roads, landings, skid trails and cableways. All
commercial and potentially commercial timber trees, trees to be felled (with a minimum of 20 m
between two marked trees), seed trees, climbers to be cut, advanced growth for retention, mature
species of importance for wildlife, important species and areas for local non-timber forest produce
and biodiversity conservation, and filter/buffer strips for watercourses must be designated in the
logging plan 41 • This information will result from integrated inventories conducted prior to the
planning process, and should undergo subsequent monitoring through permanent sample plots and
field visits to ascertain that management objectives have been met (ITTO Draft Guidelines, 1992;
Dykstra and Heinrich, 1992; John, A.D., 1992; Jonson and Lindgren, 1990; Nair, 1991; Wilkie et al.,
1992).
The type of equipment to be used in a logging operation must be specified in a plan, as must the
timing of the operation. The timing of logging operations will take into consideration rainy seasons,
seedfalls, and the reproductive cycles of animals or species of non-timber value; contingency plans
41 In the Guidelines for the Selective Logging of Rainforest Areas in North Queensland State Forests and Timber
Reserves, for catchment areas> 60-100 ha, 30 m buffer strips are the required minimum for watercourses 20 m or more;
20 m buffer strips are required for watercourses between 10-20 m wide; and 10 m buffer strips for those up to 10 m wide.
The ITTO, in its Draft Guidelinesfor Conserving Biological Diversity in Forests Managed/or Timber, recommends 20
m wide buffer strips along streams less than 20 m wide, and 50 m buffer strips along larger streams, rivers and lakes.
These buffer strips provide vital habitat for many species of wildlife.
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should be established for severe storms and other extreme events 42 • A floristic shift in diversity can
result if parent trees are removed before fruiting or shedding of seeds occurs (Uhl et al., 1981). In
the Malaysian Uniform System, the rule of thumb is that "felling must follow seeding".
Local communities should be consulted about the timing of logging operations, and logging cycles
should attempt to compliment the slack time in the agricultural cycle, so as to provide jobs for local
people (Dykstra and Heinrich, 1992). Local people should also be infonned of logging operations and
consulted on the timing with regards to the harvest of NTFPs. They should be allowed access to
complimentarily harvest NTFPs prior to logging, as with the cutting of rattan 43 , the collection of
oil producing seeds and tapping of essential oils from valuable timber species such as Carapa
guianensis and Copaifera species in the Amazon, or the collection of medicinal barks, such as those
on the important timber Tabebuia species used to treat cancer, or Myroxylon balsamum in Peru.
Following logging, local communities should be provided access to collect fuelwood and other
products 44 •
Harvest planning requires an initial increased expenditure, but cuts down on problems and costs by
reducing wastage and increasing efficiency. Well-planned harvesting operations are not only
preferable from a sustained use perspective, but have proven to be a great deal cheaper, as we11 45 •
Road Construction
In poorly planned logging operations, roads tend to occupy an inordinate portion of the forest. A.D.
John (1992) found that roads and loading or landing areas occupied 6-20% of the forest area in
Malaysia, and Uhl (1989) found roads to cover 8% of the logged forest in the eastern Amazon.
Additionally, roads in tropical forest logging operations tend to lack effective drainage and sutface
materials, so are susceptible to rain and traffic, resulting in > 90% of the soil erosion resulting from
timber harvesting (Jonson and Lindgren, 1990; FAO, 1977). Dykstra and Heinrich (1992) find roads
to be "unquestionably the most problematic feature of timber-harvesting operations". But competent
technical supervision and planning can drastically minimize erosion and increase the retention of
forest cover. In North Queensland, the width of major extraction roads was limited to no wider than
7.5 m, and for minor extraction roads 5.0 m; road grades were generally restricted to 8 degrees (14%)
and 46-58 degrees (dependent on soil types) for sidecut roads (North Queensland Guidelines). This
42 In North Queensland, no ttfelling of trees or snigging or hauling of logstl was allowed between 1 January and 31
March in any year, except when drainage works were completed by 31 December in the previous year and weather
conditions were suitable.
43 In Sabah, Abdillah and Phillips found that logging resulted in a 76% reduction in the number of valuable
commercial rattan and increased the number and size of patches devoid of rattan. The felling and extraction of timber
accounted for 95% of this damage.
44 In The Philippines, shifting cultivators settled recently logged-over forest and, utilizing income from the extraction
of remaining timber and charcoal production, and applying knowledge of forest dynamics from their places of origin,
developed a sustainable perennial tree-crop and root based agroforestry system, reflecting an interactive process of change
and adaptation between natural and human systems (Fujisaka and Wollenberg, 1991).
45 The UNDP/FAO Forestry Development Project Sarawak found that improved forest management and harvesting
resulted in a decrease in residual damage and a 20% reduction in costs. The Celos Management System in Suriname
reported less residual damage to trees, less total disturbance of soil, and a 20-45% reduction of costs overall as a result
of well-planned harvesting operations (de Graaf and Poels, 1990; Hendrison, 1990).

is in marked contrast to an average width of logging roads in Papua New Guinea reported by the
FAO in 1989 as 18.4 m, and the average total deforested width of primary roads of 60 m in a logging
concession in the Republic of Congo (Wilkie et al., 1992).
Perhaps the largest impact of logging roads is the access they provide for small-scale loggers, hunters
and fanner to once inaccessible land, timber trees and populations of wildlife (Davies, 1987;
Caldecott, 1989; Dahaban, Nordin and Bennett, 1992). Guidelines for sustainable logging usually
recommend the prompt closure or replanting of roads upon completion of the felling cycle. Many will
deteriorate very quickly of their own accord due to the climatic extremes common in these regions 46
(Redford, 1990).
Felling Operations
Selective felling of trees can mimic natural tree fall, but in reality is usually far more destructive. The
extent of felling damage is largely determined by the felling intensity, or the number or volume of
trees felled per hectare. The Celos Management System found that a maximum of 5-8 trees per ha
can be sustainably extracted from most tropical rainforests (Hendrison, 1990). Felling damage can
also depend on the training and supervision of crews (for example, many crews do not know to make
an undercut to direct the fall of a tree). With proper planing and measurement, the Celos Harvesting
System crews felled 80% of trees in the desired direction, that is towards skid trails and gaps. Only
11 % fell in an unfavourable position (Hendrison, 1990). Once down, proper cross-cutting of trees can
maximize the value of the tree and reduce wastage. Manual pit-sawing, hand-held power chainsaws,
or portable sawmills can produce boards and blocks, although these might be of lower quality than
those produced in a mill; additionally, these systems do not require road construction and heavy
machinery, so minimize damage to the forest (Dykstra and Heinrich, 1992; Jonson and Lindgren,
1990; Hartshorn, 1990; Davies and Richards, 1991). The percentage of felled timber left unutilized
in the forest is generally twice that in temperate regions. Combined with wastage during
manufacturing, total timber utilization rates can be as low as 30% (Jonson and Lindgren, 1990).
Cutting climbers prior to felling can also reduce damage and wastage by reducing the number of trees
(many of the pole-sized classes that could form the next crop of commercial species) knocked over
or broken by 25-50% (Dykstra and Heinrich, 1992; Jonson and Lindgren, 1990). Proper felling
techniques can reduce the area logged each year to provide the current volume of tropical industrial
roundwood.
Skidding and Yarding Operations
Most logging in tropical forests is characterized by heavy hauling and transporting machinery that
is capital-rather than labour-intensive. This equipment, largely developed for other purposes, has
become common to tropical logging operations since the 1950s, and has contributed to a 13-fold
increase in the use of tropical hardwoods by the main importing countries (John, A.D.; Whitmore,
1990). Conventional ground skidding equipment and extraction practices result in two major forms
of damage: excessive damage to residual trees and advanced regeneration because skidders tend to
wander through the forest in search of felled trees, which leads to a proliferation of skid trails; and
46 In the Amazon, roads have offered alternative transport for forest communities historically dependent upon the elites
who violently controlled river transport, and so the trade in every forest commodity. If land title is assured for forest
residents prior to the opening of roads, the movement of settlers and resulting unrestricted harvests of forest products can
be somewhat minimized (Clay and Clement, 1993).
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soil disturbance and compaction, which increases the potential for erosion and retards the growth of
regeneration (Dykstra and Heinrich, 1992)47.
There also exist a number of potentially less-damaging alternative extraction systems. Cable systems
reduce road needs and soil disturbance, but require highly skilled crews and are complicated and
expensive to run. The ecological impact of manual extraction is minimal, but severely strains the
laborer, and protective gear is rarely available. Animals have become a somewhat popular alternative
to conventional mechanical skidding equipment. In Asia, elephants have long been used to extract
logs, and in Latin America and Asia, bullocks and oxen are employed. The advantages of this system
are the minimal ecological disturbance, high flexibility and adaptiveness, low investment costs, and
intensive labour requirements, which results in the employment of more local people. The
disadvantages include the need to care for the animals even when they are not being used, the loss
of efficiency when harvesting logs > 70 cm dbh, and the relatively slow pace compared with
mechanical equipment. In Palcazu, Peru, it was found that the positive attributes of this system far
outweighed the negative (Ocana-Vidal, 1992; Hartshorn, 1992). Other alternative forms of extraction
include railways, helicopters, and balloons, although none have caught on to any great extent (Jonson
and Lindgren, 1990).
Unlike tree fall gaps, mechanized transport of felled trees over the forest soil has no natural
equivalent and damages the flora and soil beyond anything comparable to damage caused by large
herbivores inhabiting the forest or by fallen trees sliding downhill (Hendrison, 1990). As a result, the
objective of harvesting operations can only be to minimize negative impacts on both the potential
timber and the many existing and potential non-timber values provided by the forest in which it is
carried out.
Post-harvest Assessments
Post-harvest assessments determine the level to which a harvesting plan has been implemented and
management objectives achieved. They are critical for sustainable forest management, as harvest
plans are not often followed in spirit nor in practice. These assessments include: a report on operation
costs and revenues, an evaluation of the degree to which silvicultural, non-timber product, and
biodiversity conservation objectives are met, residual stand characteristics and the extent of damage,
area disturbed by roads and skid trails, the quality and quantity of regeneration, and the extent of
revegetation and closing of skid trails, landing sites and logging roads. The results of these
assessments must be shared with crews, and financial incentives or penalties imposed for the quality
of the work (Dykstra and Heinrich, 1992; de Graaf and Poels, 1986; Jonson and Lindgren, 1990).
47 But damage caused by ground skidders in combination with bulldozers, by far the most common method of
extraction, can be minimized. Low ground pressure tracked skidders cause less damage to the soil than wheeled skidders.
Pre-planned skid trails, directional felling toward skid trails, and winching of logs from the stump 10 the skid trail when
possible, can lead to a reduction in residual forest damage, in the number of merchantable logs left in the forest, and can
reduce costs by a third (Dykstra and Heinrich, 1992; Jonson and Lindgren, 1990; Hendrison, 1990). The Celos Harvesting
System, incorporating these practices, resulted in twice the production of conventional skidding, 8% damage to residual
forest in the extraction of 8-10 trees (as compared with 14% resulting from conventional felling and skidding operations),
and 40% less time required per unit product transported (Hendrison, 1990).

Box 3: Inventories of Non-Timber Forest Products for Natural Forest Management
An inventory of NTFPs should provide a reasonably precise estimate of the total number of halVestable
trees per hectare. For fruit and oil species, this means the total number of adult trees, for latexproducing
species, medicinal plants and rattan, some juvenile trees may also be included. Before
initiating field work, the merchantability limits of the resource should be established (peters, 1993).
Assessment of NTFPs conducted in Ghana varied by plant type. For climbers, the number of stems is
counted, and for herbaceous species the number of plant groups (clumps). For cane, the numbers of
mature, immature, and cut stems are recorded; this will provide a crude indication of plant densities and
exploitation levels (Falconer, ODA, 1992).
The inventory should also provide data on the current population structure or size-class distribution of
the species. The minimum diameter limit will be far below that for timber species, and will vary
depending upon the size and abundance of species. For species that occur at relatively low density, 10
cm dbh may be reasonable; more abundant species will probably require a slightly higher diameter cutoff
(peters, 1993; Falconer, 1992; Boom, 1989). Tree sampling methods should be modified to
incorporate species of economic importance that are halVested when small. In Ghana, for example,
Garcinia epunctata is harvested at between 5-10 cm dbh for chewsticks (Falconer, 1992). In conducting
an inventory of xate, allspice and chicle in Guatemala, Reining et al. (1992) set minimum diameter
limits at 10 cm dbh for all species except allspice, which was measured down to 5 cm dbh. Gentry
(1992) suggests that in the study he conducted with Peters (1989), in which they attempted to document
the actual value of a single hectare of Amazonian forest, their values were probably underestimated
because they did not include species utilized for fibre and medicine that are usually harvested from
plants < 10 cm dbh (Gentry, 1992).
A predetermined percentage of the area is sampled using plots or transects (of square or circular
configuration), stratified among different forest types found within the area. NTFP inventories must
often be incorporated into on-going inventory work. In Ghana, the NTFP inventory was forced for
logistical reasons to use an existing sampling design of 1 ha sample plots stratified systematically.
Temporary sample plots were established in forest logged within the last three years and in unlogged
forest to assess the effects of varying intensities of logging on NTFPs (Falconer, 1992).
Permanent sample plots, which can provide data on changes over time, should be established to monitor
the impacts of non-timber and timber extraction on forest products. Ideally, plots should be random and
stratified by forest type (pairs of 1 ha each), and probably of square or broadly rectangular shape to
minimize edge effects and because they are faster and easier to demarcate than circular plots in most
tropical forests. Plots will be periodically re-inventoried, usually every five years (Alder and Synnott,
1992; Reining et al., 1992).
The exact number of PSPs used will depend upon the abundance of populations - high-density
populations will require fewer plots than scattered, low-density populations, which must be more
intensively sampled (peters, 1993). The ODA Forest Resources Management Project in Ghana has
established 629 100 m x 100 m PSPs to provide information on the NTFP growing stock and to
measure the growth of individual trees in different forest types. In two sub-plots of each, trees will be
measured down to 1 cm dbh so as to collect data on the species harvested at small sizes.
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In this way, regeneration of species commercially harvested at much larger diameters can also be
assessed, and the intensity of halVesting practices reduced if the density of seedlings and saplings are
found to drop. The effectiveness of this harvest reduction will be verified and adjusted, if necessary,
during the next inventory. (peters, 1993; Falconer, 1992; Salick, 1992). In the Si-a-Paz International
Peace Park in Nicaragua and Costa Rica, stratified random subplots, totalling 10% of the PSPs
established to measure regeneration, are used to inventory and voucher, with the help of a local,
knowledgeable infonnant, useful plants and their community characteristics (species richness, diversity,
density and cover) (Salick, 1992). The interview/inventory technique, involving the collection of plant
specimens and the subsequent interviewing of informants as to names and uses, was employed by Boom
(1989) in his study of the ethnobotany of the Chacabo Indians in Bolivia. PSPs can also be the subject
of detailed botanical inventories, which record all plants found on the plot (Falconer, 1992; Salick,
1992).
VII. Silvicultural Systems for Natural Forest Management
Silviculture and harvesting systems presuppose social, economic and ecological knowledge, as defined
in management objectives (Schmidt, 1991). The characteristic tools of silviculture include the
regulation of shade and canopy opening, treatments to promote valuable individuals and species and
reduce unwanted trees, climber cutting, "refining", poisoning, enrichment, and selection (Poore et al.,
1989).
All silvicultural systems will, to some extent, change and usually coarsen the fine mosaic of gap,
building and mature phases of a natural forest (Whitmore, 1991). Silvicultural systems that aim to
maximize the variety of products extracted from the forest and retain species diversity should change
the natural composition and structure of the forest as little as possible (Poore and Sayer, 1991;
Parren, 1992). As the ITIO Guidelines for Sustainable Forest Management (1990) suggest: "the
choice of silvicultural system should be aimed at sustained yield at minimum cost, enabling
harvesting now and in the future while respecting recognized secondary objectives". In many cases,
non-timber objectives will not be considered secondary and will have an economic and social value
of equal or greater importance than timber; silvicultural systems should be selected and adapted to
reflect this value.
Silvicultural systems for natural forests are grouped into the polycyclic and monocyclic. Monocyclic
systems remove all saleable trees from a forest at a single operation, resulting in bigger gaps in the
canopy best suited for the growth of pioneer species with light, pale marketable timber (Whitmore,
1991). Monocyclic systems dramatically alter forest structure and species diversity, and so severely
limit any long-tenn harvesting of non-timber forest products.
Polycyclic systems are usually more conducive to conservation and non-timber objectives, although
it must be said that neither system truly reflects multiple-use management objectives that specifically
promote the sustainable harvest of non-timber, as well as timber, products (Nair, 1991). Polycyclic
systems result in scattered gaps in the canopy, favouring slower growing shade-bearers, and relying
on the release of advanced regeneration of commercial adolescents on the forest floor. Under the best
conditions, these systems can increase the timber yield over a full rotation, but this depends largely
on the intensity of and residual damage incurred by timber harvesting, subsequent competition from

colonizers, and the success of advance regeneration that survives the microclimate changes resulting
from canopy opening (Nair, 1991; Whitmore, 1992). "High grading" or "creaming" of commercial
species that display desirable traits can result in disgenic effects in polycyclic systems, and must be
carefully controlled (Hendrison, 1990; Queensland Guidelines).
Natural forest management systems can be extensive or intensive. Intensive management has proved
extremely problematic in the multi-age class and multi-species tropical moist forests due to our
ignorance of the ecology of commercial species and the ecosystems in which they operate (Poore,
1989). Extensive systems range, with increasing productivity and costs, from the "wait and see"
demarcation of forests, to the "log and leave", to the minimum intervention, stand treatment and
enrichment planting of low intensity natural regeneration silvicultural systems (Poore, 1989; Jonson
and Lindgren, 1990). With increasing intensity in forest management, there exists a trade-off with
the conservation and non-timber values associated with a forest. "Wait and see" and "log and leave"
forests (providing logging damage is minimized) will provide the most opportunity for the
conservation of forest structural and species diversity and the variety of products resulting from this
diversity. But in many forests timber production will be a primary management objective. Low
intensity management, utilizing polycyclic, natural regeneration silvicultural systems, produces larger
volumes of timber, while - to varying degrees - maintaining non-timber values. Low intensity,
polycyclic management of natural forests can be broken down into three, more or less distinct,
systems: light selective logging, light selective logging and silvicultural treatment, and light selective
logging and enrichment planting 48 •
Light Selective Logging or "Minimum Intervention"
This is the simplest system, relying on silvicultural knowledge and using models to define the
sustainable harvesting intensity, girth limits, and cutting cycles. Only stems of marketable species are
removed, no other species being interfered with. Natural regeneration fills the gaps created by felling,
without manipulation or enrichment. Forests managed in this way must be sufficiently stocked with
timber trees of large dimensions to make utilization profitable. Management includes inventories and
harvest planning. Upon completion of felling operations, the forest is closed until the next cycle.
Although the growth rates of commercial species "managed" in this way are often considered
uneconomically low, light selective logging, or "light creaming", is still widely practised in the
tropics, can be integrated into existing NTFP harvesting practices, and is one of the least destructive
land use systems practised in the tropics, provided responsible harvesting practices are employed
(Gomez-Pompa and Burley, 1991; Poore, 1989; Jonson and Lindgren, 1990; Hendrison, 1990).
Light Selective Logging and Stand Treatment
In these systems logging is carried out as described above, but is followed by treatments to "direct"
natural regeneration to increase the representation of commercial species. This includes the poisongirdling
and weeding of undesirable species, and the cutting of competing lianas and brush, but does
not include direct measures to change the forest structure (Jonson and Lindgren, 1990). Because
tropical moist forests contain a mix of tree species, "refining" is employed to eliminate the
undesirable competitors of commercial species. Competition is reduced by: liquidating all non-
48 These types of silvicultural systems attempt to answer the following questions: are there sufficient seedlings,
saplings, and advanced growth of merchantable species at the time of exploitation to provide adequate stocking for the
next crop? what are the silvics of these species (most importantly their regeneration potential) and what ·treatment will
be necessary? and what are the probable rates of growth and merchantable volume expectations of the different species?
(Wyatt-Smith, 1987).
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28
desirable species (and defective individuals of desirable species) above a planned girth limit;
individual release of "leading desirables"; and liquidating non-desirables starting with the biggest
trees downwards until a predetermined residual basal area is attained (van der Hout, 1992)49.
It is difficult to detennine the change in forest productivity due to refinement, since growth
variability is so extreme, and is influenced by so many interacting factors that it is "sufficiently
random to frustrate any attempt to interpret it in detenninistic tenns" (Wadsworth, 1987; Schmidt,
1991). "Sustainability" cannot be detennined before the third felling cycle, and this type of data is
not currently available (Nair, 1991). Refining is also a direct attack on the ecological diversity of
forests, and may gradually eliminate more than half the tree species. De graaf and Poels (1990) admit
ignorance of the ecological effects of reductions in the numbers of non-commercial species.
Wadsworth (1987) suggests that developing additional uses for the existing forest stock would be
preferable to attempts to induce something that does not already exist in the forest - that is, try to
do through processing and marketing what is attempted through poisoning (although the harvest of
larger numbers of species creates the danger of increased logging intensity).
The less tampering done with the undergrowth, top soil and microclimate of the forests, the easier
it is to maintain the ecosystem commercial trees are dependent upon (Dawkins, 1958; Meijer, 1970).
Meijer (1970) found that girdling the undergrowth in dipterocarp forests could enhance conditions
for the invasive nomad trees for 20-40 years. It has also been found that species deemed
noncommercial, and so "refined", have later proved to be important keystone species, or have
exhibited significant economic value, if not a greater value than those their absence has liberated
(Schmidt, 1991; Hammond and Brown, 1991; ITTO, 1992). In the Celos Management System,
commercial species are "defined on market criteria and the technological qualities of the wood". In
the forest area in Suriname where they work, this amounts to only 40-50 species (de Graaf and Poels,
1990; 1991). There is obviously little room in this system for the development of markets for
additional timber species or any long-term non-timber forest product extraction.
But the CMS, and other systems like it, are attempting to create a fine balance between what is
considered to be the uneconomically slow growth of commercial species in natural forests without
silvicultural treatment, and the need to retain forest structural and species diversity. Many find that
for timber production alone, logging without silvicultural treatments is not sufficiently economical
(de Graaf and Pools, 1990; Silva et al., 1992; Chelunor Nwoboshi, 1987). In many areas, however,
the economic and social importance of timber is equal or even secondary to that of non-timber
products, and silvicultural treatments that coarsen forest structure and greatly impact forest diversity
should be abandoned. Whitmore (1992) notes that in large part post-harvesting treatments have been
abandoned due to their expense, and that growth rates can be improved through the control of logging
operations. Thus, timber felling, usually regarded as the first major silvicultural operation in a natural
regeneration system, has become the only canopy manipulation the forester can afford (Wyatt-Smith,
1987; Whitmore, 1992).
49 Refinements are expected to reduce the cutting cycle from 60 to 30 years in Sarawak, and the shifts in species
composition it produces have been credited with 50-250% gains in yield (van der Hout, 1992; Wadsworth, 1987). De
Graaf and Poels (1986; 1990) found that the reduction of non-commercial species by refinement (which eliminated 1(1­
2/3 of the standing stem volumes of these species) produced an increase in annual production of commercial timber to
2m 3 /ha from 0.5 m 3 /ha. Wadsworth (1987) found that refinements most significantly created gains in quality, and not in
increased wood volume.

Climber cutting is a perhaps less controversial issue in natural forest management. Climbers not only
smother regeneration in logged over forest but, by binding trees together, can result in the destruction
of large groups of trees during felling operations. It has been found that climber cutting, at least a
year in advance of logging operations, reduced the number of trees pulled down during felling by 1/4
(Jonson and Lindgren, 1990)50.
Many climbers play an important role in local and international economies, and these should be
harvested prior to the felling of timber, and any endangered species carefully avoided. Rare
Ancistrocladus climbers in Cameroon, for example, have yielded potential anti-HIV compounds,
which could generate significant economic returns should a pharmaceutical be developed (Katz­
Miller, 1993). The Amazonian liana Chondodendron tomentosum, used in curares, or arrow poisons,
of Amerindians in Colombia, Ecuador and Peru, was found to contain the valuable skeletal muscle
relaxant tubocurarine (Schultes, 1992). Amazonian shaman often cultivate the wild liana
Banisteriopsis caapi to prepare the hallucinatory ayahuasca for ceremonies (Schultes, 1992). Gnetum
bulchozi and Heinsia crinita are sources of important spinach-like greens in diets in West Africa
(Agwu, pers. comm., 1993). Climbing palms are also important in this region for household and
commercial weaving, including Eremospatha spp., Laccosperma opacum and Calamus deeratus
(Falconer, 1992).
The neotropical Desmoncus species have shown similar growth habits to the valuable Calamus
species of rattan, are used in basket-making by indigenous peoples, and have been suggested as
potential substitutes to Southeast Asian rattan (Gentry, 1992; Clay and Clement, 1993)51. Recently
a cottage industry in rattan products has sprung up around Iquitos, Peru, where there is already a
thriving fibre industry based on the aerial roots of Philodendron solimiesensis, which have long been
extensively used in campesino handicrafts (Gentry, 1992). Many of these fibre plants occur in
second-growth forest, and their utilization could generate substantial incomes locally. Fevillea spp.
have seeds richer in oil than any other dicot, and Amerindians in Peru use them as candles (Gentry,
1992).
Light Selective Logging and Enrichment Planting
In these systems, saplings of desired species are planted in lines or patches where stocking of residual
stems is low. Species planted are usually rapid-growing, and can result in the gradual elimination of
existing stands (Wadsworth, 1983). In Venezuela, researchers have found a more than 30% drop in
species in strips planted with non-indigenous timber. The impact of enrichment planting was
particularly pronounced on specialist species (Grajal, pers. comm., 1993). The IITO Draft Guidelines
for Biological Diversity Conservation in Forests Managed for Timber (1992) and The Global
50 Following logging, the greater sprouting capacity ofclimbers, their competitive investment in resource procurement
surfaces (relying on the trees' supportive tissues), and the climbing structures abundant in the slash of logged-over forest,
often lead to the smothering of seedlings, damage to poles, and the formation of climber tangles through which
regeneration has difficulty emerging (Fox, 1968; UbI et al., 1981). Pioneers might be better suited to survive climber
infestations than climax species, as they are often flexible and fast growing, and have large compound leaves or leaf-like
branches which may help them shed lianas (putz, 1984).
51 The high economic value of rattan in Southeast Asia have resulted in organized teams (not always made up of local
people, who may not be informed of the timing of logging operations or as aware of their implications as outside
merchants and traders) extracting rattan prior to logging (Abdillah and Phillips; Stockdale, pers. comm., 1993).
29

30
Biodiversity Strategy (1992) recommend that enrichment planting use native wild seedlings or
seedlings raised from locally collected sources. Recent research on enrichment planting of native
species has suggested that, contrary to existing beliefs, native species can often be more productive
than the exotics which replace them although in some cases these plantings could suffer from
predation due to changes in density-dependent plant-herbivore relations «WRI et al., 1992; Hartshorn,
1980).
Enrichment plantings of multi-purpose species, such as Carapa guianensis (an important timber
species in the Amazon, the seeds of which yield a valuable medicinal oil), Caryocar villosum (an
important timber and fruit tree in the Amazon), and Brazil nut (Bertholletia excelsa) has been tried
in some areas of the Amazon (Clay and Clement, 1993). Traditional agroforestry and forest
management systems often employ enrichment plantings of desirable species (Alcorn, 1990; Gomez­
Pompa, 1990; Balee, 1989). Clement (1993) suggests that enrichment planting with NTFP species
could have the added benefit of introducing high-quality gennplasm into the forest. Combined with
natural regeneration strategies, this could lead to an increase in yield and market quality. Gennplasm
collections are expensive to develop, maintain, characterize and evaluate correctly, so traditional
home gardens would probably provide the best varieties for enrichment (Clay and Clement, 1993).
Clearing Systems and NTFPs
In addition to the low intensity systems described above, some of the more intensive clearing systems
(as defined by Gomez-Pompa and Burley, 1991), promote the natural regeneration of valuable
commercial species and eliminate the undesirables; future forests are thus enriched with propagules
coming only from the commercial species. Mature trees, seedlings and juveniles of most undesirable
species are eliminated. As a result, the forest is converted from a multi-species, multi-aged to a more
or less even aged forest with a greater percentage of commercial species.
Although they utilize natural regeneration, these systems have a strong affinity to conversion and
leave little room for the harvest of a significant variety of non-timber forest products (van der Hout,
1992; Chiew Thang, 1987). Wyatt-Smith (1987) remarked that an example of this system, the
Malaysian Unifonn System, produced areas that resemble Shorea plantations. These systems have
proven extremely difficult to implement because: the soil seed bank produces numerous undesirable
species, which require expensive cleaning and weeding operations; the commercial species may not
flower for several years; the opening of the overstorey to favour rapid growth also stimulates weeds
and climbers; and knowledge of the growing stock, its distribution by species, size classes and
location and how these change with harvesting and treatment is extremely limited. (Gomez-Pompa
and Burley, 1991; Wadsworth, 1987; Schmidt, 1991). After 38 years of effort to regenerate forest in
Nigeria under the Tropical Shelterwood System, failure was admitted and the project terminated
(Wadsworth, 1987).
However, the strip clear-cutting, or strip shelterbelt, system employed by the Yanesha Indians in the
Palacazu Valley in eastern Peru, has proved promising for natural forest management, and efforts
have been undertaken to incorporate non-timber forest products into forest management (Salick,
1992). The project is attempting to find markets for a variety of wood products and a large number
of species, while promoting vertical integration of processing industries. Long (200-500 m), narrow
(30-40 m wide) strips are clear cut, and rotated through the forest in 30-40 year felling cycles in such
a way that the undisturbed forest provides a source of propagules for regeneration (Hartshorn, 1990;
Gomez-Pompa and Burley, 1991; Jonson and Lindgren, 1990). Buffer zones are retained along

watercourses, steep slopes, and smaller reserved areas are set aside every six strips. Disturbance by
weeds, climbers and pioneers, and the removal of nutrients stored in forest vegetation could influence
the rotation and species composition of the forest, but natural regeneration of commercial species
from seed and coppice appears to be "sticking" (Hartshorn, 1990; Jonson and Lindgren, 1990).
Gentry (1992), found that the current approach to harvesting does not yet make the most of the
forest's diversity. Small trees (and branches) are used for charcoal, medium-sized trees for posts and
telephone poles, and large trees for timber. Thus, in essence, "the diverse forest is treated as though
it consisted of three species", and the potentially higher value of individual species as fruits,
medicines, nuts, latexes, ete. is lost (Gentry, 1992).
Salick (1992) has undertaken a study to determine the number of plants regenerating in a cleared
experimental strip that are useful to the Yanesha. Overall, the number of useful plants and plant
species increased dramatically, due to the small size of individuals and changes in species
composition resulting from the early successional nature of the strip. In some cases, however, some
of the herbs and small grasses collected were found to be rare, and may have unusual gap niches
(Salick, 1992). Some species of importance to Yanesha subsistence were lost, however, and there is
no evidence that they will regenerate in the near future. These include medicinal, construction
materials, arrow poison, thatch and - most importantly - Heteropsis and Maregravia spp. used to
weave baskets, mats, and in the construction of houses, fish traps, and baby hammocks. These species
are becoming increasingly scarce in this area, and must be collected as much as a day's walk away
(Salick, 1992)52. Salick (1992) recommends that Yanesha indigenous management practices and their
use of secondary forest products be integrated into strip management.
Polycyclic, selection systems relying on natural regeneration have many limitations. Nair (1991)
reports that there exists no case in which such a system has been applied over a number of cycles
continuously. Management plans are continually revised to include new areas for timber extraction
and reduce felling cycles and girth limits. Because of improved accessibility, the increase of lesser
known species with markets, and the acceptability of low girth logs for industrial use, Nair (1991)
believes that selective logging is in danger of being replaced by clear-felling, more intensive systems.
Dawkins (1958), while describing selection systems as the ideal form of management for forests
which are little understood and where violent conversions are liable to cause irreversible and
unfavourable changes in forest ecosystems, found selection systems difficult to manage and
52 Salick (1992) found that the regenerating forest included fewer species of palms and fewer individual ferns than
the original vegetation, whereas more species and individuals of herbs and grasses were found. The post-harvest treatment
of cutting and levelling slash apparently encourages the increased dominance of vines throughout the strip. Strip
regeneration is different from natural gap fonnation, and resembles swidden fallows in the proportion of secondary plant
species encountered and the importance of coppicing as a source of regeneration.
31

32
uneconomical 53 • But improvements in ecological knowledge, logging practices and an increase in
the use of lesser-known-species have been shown to alleviate many of the problems associated with
these systems.
Most importantly, well-run selection systems are the only systems that serve natural forest
management objectives geared towards producing the best total return from all forest products
without depleting the resource base (although the strip-clearing cutting system described could have
promise in some areas)54. Not all forests designated for timber production should be under lowintensity
management, but the current unpredictability of both forest ecosystems and markets for
forest products argues for a significant portion of the forest reserves of a country to be flexibly
managed for a wide range of timber and non-timber values (Poore and Sayer, 1991; ITTO, 1992;
ITIO, 1990).
53 As summarized by Wadsworth (1987), Dawkins' argument against selection systems is that: the removal of 10-12
mature trees/ha may be economically marginal; the yield of 3.5 m 3 /ha/year is far less than that of plantations; the cut
destroys 20-250/0 of the adolescent and pole stocks and damage tends to be progressive; longer cycles mean a larger
harvest but with more damage and fewer trees remaining for future crops; shorter cycles reduce the yield/cut and increases
the damage per area per unit of time; large crown diameter/dbh ratios (20+) required for rapid-growing species must
develop early but cannot be obtained beneath larger trees; and yield prospects, where there is no market for intermediatesized
trees, are no more than 1.4 m 3 /ha/year.
54 As Dawkins (1958) said himself, "where forest commerce is primitive and forest science underdeveloped, the
conservative course is to retain as many existing trees over as wide an area as possible, for fear that what is lost can never
be replaced".

Box 4:
Examples of Multi-purpose Amazonian Species with Present and Future Potential for
Natural Forest Management
Brazil nut (Bertholletia excelsa) is an ideal multipurpose species. It is light-demanding and could be
planted in larger gaps following logging operations. It yields nuts after 15-20 years and timber after 50­
100 years. Mature trees can yield 100-225 kg of unshelled nuts in a good year. Although it is illegal to
fell a Brazil nut tree, large numbers continue to be cut for its fine timber (Smith et al., 1992). Brazil
nut grows quickly with little vulnerability to pests and diseases, and with little intervention. Nuts are
harvested in the rainy season, while rubber, its compliment in extractive systems, is tapped during the
dry season (when timber harvesting operations also take place) (Clay and Oement, 1993; Balee, 1989;
Mori, 1992; Richards, 1993).
Andiroba (Carapa guianensis) is a fast growing moderate shade-bearer. Andiroba is widely distributed
in the neotropics and is frequently found in the Amazon basin in association with Virola surinamensis
and Hevea brasiliensis, both mUlti-purpose species (Sampaio in: Clay and Clement, 1993; Tropical
Woods, vo!. 90, 1947). The wood of andiroba is considered one of the Amazon's fmest (Record and
Mell, 1924). The seeds of andiroba produce an extremely bitter oil (its name derives from the Indian
words "nhandi" (oil) and "rob" (bitter). Small quantities of oil are used to sooth muscular distentions,
skin tumours and superficial skin ailments. The Indians of French Guiana extract oil of the andiroba
seed, mix it with Bixi oreallana, and prepare an ointment applied to the skin to prevent mOSQuito and
flea bites. Andiroba is an ideal species for enrichment planting following logging. Its seed oil could
provide annual income after the tenth year until the trees are large enough to cut for timber at between
18-23 years (Sampaio, 1993 in: Clay and Clement, 1993).
Andiroba is endangered in its natural habitat, and was proposed for inclusion in Appendix 11 of the
Convention on International trade in Endangered Species (CITES) (Wellner and Dickey, 1991).
Copaiba (Copaifera multijuga) is a large tree that can attain 36 m in height with a dbh of up to 80 cm;
average dbh is between 40-50 cm (Alencar, 1981). It generally occupies the upper canopy and may
occasionally be an emergent. Like other upper canopy and emergent species, C. multijuga requires
shade during the seedling stage but requires sun in order to attain height and girth (Sampaio in: Clay
and Clement, 1993). C. multijuga is widely used for sawn lumber, construction and carpentry, and
makes a good charcoa1 55 • Oil resin, collected by drilling a hole in the trunk of C. multijuga, C.
reticulata, C. guianensis and C. officinalis has large regional and international markets. It is used as a
component of high temperature resistant varnishes, as a perfume fixative in cosmetics, antibacterial in
creams and soaps, as a substitute for linseed oil in paints, as a modifying agent in plastics, and to
improve the clarity of the image in low-contrast areas in photographic film development. The oil resin
is also a popular medicine in Amazonian. It is used to treat throat infections, bronchitis and other
respiratory problems, as an antiseptic for wounds and scratches, and as a cure for diarrhoea and
problems of the urinary tract. Controlled tapping of the oleo-resin of Copaijera species could yield a
continual source of sustainable income throughout the growth cycle of the tree (Shanley, 1993; Sampaio
in: Clay and Clement, 1993).
55 The wood is heavy, with a regular grain and medium texture similar to that of Cedrella odorata (Sampeio in: Clay
and Clement, 1993). Copaijera species can produce excellent export veneer with a very attractive gain. Although it is
relatively uncommon, generally of small diameter and difficult to harvest, Copaijera spp. have been cut down at
unsustainable rates in the Peruvian Amazon (Gentry and Vasquez, 1988).
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34
Piquia (Caryocar villosum) is one of the largest forest trees in most of its distribution, frequently
attaining 40-50 m when occurring as an emergent above the canopy. Piquia does not regenerate well in
the shade of the high forest, but growth is rapid when released by increased light (Clement, 1993).
Piquia represented 1.1% (26,540 m 3 ) of the timber commercialized in Manaus in 1972. The wood is
used for ship-building, civil construction, and general carpentry. Amerindians rely heavily on its fruit,
and caboclos know the location of most trees and visit them frequently during harvest season. Piquia
could be planted in the larger gaps left after logging (Clay and Clement, 1993). Piquia is endangered;
Caryocar costaricensis is listed in Appendix 11 of CITES (Wellner and Dickey, 1991).
Pau Rosa (Aniba Duckei) reaches up to 30 m in height. Its wood is used in cabinetry, but its primary
economic importance is the production of aromatic essential oil. Pau rosa is locally extinct in many
parts of the Amazon, and is currently only found in inaccessible areas. To harvest the essential oil, the
tree is cut, the wood cut into small chips and the wood pulverized. One ton of wood chips produces
only 9 kg of the oil. (Alencar and Fernandez, 1978). Pau rosa grows well in both full sun and partial
shade. It would be an ideal component in a natural management system, as it is a high value, low
volume product that can be processed locally (Richards, 1993).
Ucuuba (Virola surinamensis) can attain a height of 35 m and dbh of 45 cm in the forest. The wood is
easy to work and is widely used in light carpentry, for shipping boxes, match sticks, plywood and pulp
for paper. It is heavily exploited for plywood, and commercial timber size trees in the Brazilian
Amazon are extremely rare today. The seeds contain oils useful to the perfume and cosmetics industry,
and are locally used to treat rheumatism, stomach aches and dyspepsia. Cooked bark is used to sterilize
wounds and aid healing. Its sap is used to treat haemorrhoids, and the bark is ground and smoked for
its hallucinogenic effects by many Amazonian tribes (Sampaio in: Clay and Clement, 1993). In the
lower Amazon River Basin, it occurs in association with the buriti (Mauritius flexuosa), assai (Euterpe
oleracea) and ubucu (Manicaria sacci/era) palms, all of which have important non-timber uses 56
(Peters et al., 1989; Anderson et al., 1991). These forests should be carefully managed to maintain the
integrity of these valuable non-timber product yielding ecosystems. .
Cumaru (Coumarouna odorata) is a large tree of the primary forest, attaining up to 30 m, and widely
distributed throughout the Neotropics. Its primary value is its very heavy timber which is used in naval
construction, for truck and train wagons and for high-quality cabinetry. Historically, the extraction of
coumarin from cumaru seeds was nearly as important as its timber. This perfumed oil was used in the
perfume and cosmetic industries and to flavour tobacco. It is suggested by some authors that markets
for coumarin could increase in the near future due to rising interest in alternative sources of vegetable
oils for personal care products (Oay and Clement, 1993). Water extracted from the bark is used as an
antispasmodic and general tonic, and the seeds are occasionally used to make ornamental necklaces and
other handicrafts. Cumaru can grow in both full sun and partial shade, making it a good option for
reforestation or agroforestry. (Sampaio in: Oay and Clement, 1993).
S6 Buriti (Mauritius flexuosa) produces one of the most important market fruits in western Amazonian; the thin, oily
mesocarp is eaten raw, or processed into a sweet paste for candies, beverages, and ice creams; the mesocarp and seed
kemal also yield good quality oil. Local inhabitants tend to locate plantations of cacao (Theobroma cacao) at the base
of these palms (peters et al., 1989; Anderson et al., 1991).
Assai (Euterpe oleracea) is an important source of palm heart in Brazil, and its fruit pulp provides a beverage that is a
staple component of the regional diet. Local inhabitants actively manipulate the floodplain forests to promote the fruit
of this palm (peters et al., 1989; Anderson et al., 1989).

Bacuri (Platonia esculenta) is a mid-to-upper canopy species, requiring full sun for good growth and
yield. It is one of the most popular fruits in the Belem market and is used in jams, ice creams and as is.
The yellow latex (both from the fruit and the trunk) has medicinal properties, specifically when applied
topically for skin ailments. The heavy wood is employed in general carpentry and furniture making, as
well as in civil and marine construction. Because it does well on nutrient poor soils and in full sunlight,
bacuri could become a useful species for recuperation of degraded lands (Clement, 1993).
Jatoba (Hymenaea courbaril) is generally a large tree, attaining 40 m in height and 2 m dbh. It is
occasionally cultivated and frequently managed by local people, for example by being protected when a
swidden clearing is opened. The wood is very heavy and durable and is used in heavy construction,
such as hydraulic work, truck bodies, railroad ties, etc. The resin that exudes from the trunk, the
branches and the fruit pericarp solidifies on the tree or fall in chunks to the ground, at which time it is
collected. This resin is used industrially in the fabrication of varnishes, is used locally to make kitchen
utensils, and as a sealant to reduce water penetration. In popular medicine, jatoba bark is used as a
vennifuge and to treat cystitis; the sap, when mixed with bee's honey, is used to treat bronchitis and
various heart ailments (Ferreira and Sampaio in Clay and Clement, 1993).
VIII. Traditional Management of Neotropical Forests for Timber and Non­
Timber Products
Traditional forest management has long relied on complex ecological processes to maximize the
harvest of a wide variety of forest products. Unlike natural forest management geared primarily to
timber production, which usually results in the coarsening of forest structure and depletion of species
diversity, the traditional management of the forest for a multitude of products has usually promoted
and required the maintenance of forest structural and species diversity (Gomez Pompa and Burley,
1991; Alcorn, 1990; Posey, 1989; Anderson, 1990).
Indigenous peoples have long managed critical forest resources, rather than just "adapting" to them,
and over the millennia have transfonned much of the vegetation and forest types in the tropics
through these elaborate systems of forest managemenr 7 (Balee, 1989; 1988; Posey, 1992; Schultes,
1992). Many "natural" forests, therefore, may in fact represent arrested successional forest once
managed by people, including the palm, bamboo, liana and Brazil nut forests. While natural forest
management is generally used to mean the focused management of a particular forest product ­
timber-producing trees, non-timber products, game, etc. - indigenous systems of forest management
focus on processes, not only products, although products result from these processes (Alcorn, 1989).
For example, the Ka'apor Indians of the Brazilian Amazon manage the forest to produce vegetational
zones in different phases of recovery. Each vegetational zone is managed with varying degrees of
intensity, decreasing from house gardens to young swidden, old swidden, and fallow. These diverse
vegetational zones create environments in which artificially high densities of useful plants and
57 It is suggested that at least 11.8% of the terra firme forest in the Brazilian Amazon alone is of archaic, cultural
origin (BaBe, 1989).
35

36
animals thrive to produce diverse products 58 (Balee and Gely, 1989). Similarly, the Mexican Husatec
and Peruvian Bora fanners create mosaics of eco-units. In addition to the opened lands for
agriculture, at any given time secondary successional species are reproducing somewhere in the
mosaic and mature forest species are reproducing somewhere else. In this way, the elements
necessary to regenerate forests are retained in the system (Alcom, 1990)59.
Traditional agroecosystems focus on processes, rather than spatial structures, the usual subject of
western attention. They are a fluid complex of planted fields, fallows, savanna, dooryards, forests,
rivers, and river banks, rather than distinct, static structures (Alcom, 1989; 1993). According to
Alcom (199), indigenous agroforestry systems share seven attributes: they take advantage of the
variety of native trees and tree communities, planting or protecting those most desired; rely on natural
successional processes to produce resources, improve and protect soils, and reduce pest problems;
use natural environmental variation; incorporate numerous crop and native species; are flexible and
personalisable, and may vary by site or year; spread risks by retaining diversity; and maintain a
reliable back-up to meet needs should other sources fail.
Indigenous sequential agroforestry systems that integrate secondary successional vegetation are
usually complimented by managed forest grove systems from which fruits, wood, and game are
harvested. In Huastec communities, 25% of a community's land is held in forested groves, usually
situated along creeks or on steep slopes where they prevent soil erosion and protect watersheds. They
are managed by a combination of arboriculture and natural forest management to create a mixture
of native species of primary and secondary forest, and introduced species. A typical forest grove
contains over 300 species and 90% have known uses (as food, construction material, medicine,
firewood and livestock forage)60 (Alcom, 1990).
58 Over 76% of the plant species used by the Kayapo Indians of Brazil are not "domesticated" nor can they be
considered "wild" since they have been systematically selected for desimble traits and propagated in a variety of habitats
(posey, 1992).
59 Irvine (1989) found that the Runa Indian community in Ecuador have an important impact on forest structure and
composition through succession management. Regeneration in the fallow forest is managed to develop a characteristic
form, and so alters the plant composition of the developing forests. Planting of species that can mature during the fallow
period occurs early in the agricultural cycle. Light-demanding fruit trees are planted concurrently with manioc, for
example, to benefit from the larger gap in the forest at this stage. Selective cutting of the forest understorey or overstory
during garden clearing, and subsequent weeding, also favours certain forest species as sources of regeneration. Both
planting and protection of valuable species vary from the careful to the casual. Managed fallows had a more diverse
canopy, with a higher proportion ofenrichment (8-19% planted species); unmanaged fallows were dominated by a unifonn
canopy of Caecropia spp.
60 An ethnobotanical survey conducted by Boom (1989) of the plants used by the Chacabo Indians of Amazonian
Bolivia showed that 360 (or 82%, of the tree species and 95% of the individual trees) individuals in one hectare of forest
near their principle village, Alto Ivon, were used: food (33 spp., 264 individuals), fuel (14 spp., 163 individuals),
construction and crafts (23 spp., 225 individuals), medicines (23 spp., 271 individuals) and commercial sources of cash
(2 species: Hevea brasiliensis and Bertholletia excelsa).

38
With slight modification, this could be a list of management activities employed by the forester.
Rarely, however, are these traditional management systems - developed over millennia by the
inhabitants of extremely unique and complex ecosystems - seriously considered in the design of
natural forest management 63 • Elaborate scientific studies are undertaken to articulate the subtleties of
what often amounts to a small component of traditional management systems, and extensive
ignorance of the ecology of tropical forests is widely professed. While this research is of academic
interest, it will take many decades to arrive at a well-articulated scientific understanding of even a
small portion of the tropics, and the forest manager must rely on more immediate guidance. For lowintensity,
multi-purpose natural forest management, traditional management systems provide an
enormous headstart 64 (Alcorn, 1990; Gomez-Pompa, 1991; Salick, 1992; Posey, 1988; Zemer, 1993;
Lamb, 1991).
IX. Natural Forest Management and the Conservation of Biodiversity
Approximately 1.4,000,000 species of animals and plants are known to science, and it is thought that
more than three times this number exist (Sayer, 1991). Tropical forests, which cover only 7% of the
earth's land mass, are estimated to contain well over half its species. One ha of tropical forest is
estimated to contain between 100 and 300 trees species alone, with most species being represented
by only one or two individuals per hectare. The general trend of high species diversity with low
species density has been documented repeatedly in tropical forest inventories (Peters, 1993). As a
result, tropical forest species appear especially prone to extinctions and sustainable resource
63 Admittedly, there are numerous obstacles to this, not least of which is the lack of respect western-style managers
often have for traditional systems of management that are based not upon fonnal science but rather on customary practice,
cultural traditions, and local knowledge of land and natural resources (Othole and Anton, 1993; Poole, P. 1993; Berkes
et al., 1991). Traditional, largely decentralized and consensus-based systems of management that are enforced through
social sanctions, contrast markedly with the "western" hierarchical, centralized, regulatory, and time-based systems of
management.
As the Zuni Indians Othole and Anyon (1993) state: "because the entire legal, regulatory, and guideline framework is a
non-Indian construct, it is often difficult to fit the needs of the developer and agency with the needs of the tribe ... even
the word 'property' albeit a necessity of tenninology because of the language of federal law ... can raise serious concerns
within the traditional and religious leadership".
64 For example, Salick (1992) has found that the increased dominance of secondary forest species and the importance
of coppicing as a source of regeneration in the strip-clear cutting silvicultural system employed in Palcazu Peru,
resembled fallows common to indigenous systems of forest management from the area. She recommended using
indigenous forest and fallow management as the theoretical underpinning to natural forest management; by applying these
techniques, forests may be more productive. For example, to maximize regeneration of desired species in the relatively
large gaps of the strip clear-cut, in addition to managing seed sources, emphasis should be placed on management
practices that encourage healthy coppicing, as has been done successfully in the indigenous system (Salick, 1992).
Phillips and Gentry (1993) have developed a simple quantitative technique for evaluating the relative usefulness of plants
to people; they feel that compilation-style approaches to ethnobotany must be modified by developing methods that allow
researchers to quantitatively describe and analyze patterns in what they study. In this way, ethnobotanical studies will
provide scientifically higher-quality infonnation on why and how people use plants, and so might more easily be
incorpomted into the research and design of management systems for natural forests by other scientists, including
foresters.

exploitation is a difficult management problem (Sayer, 1991; Peters, 1993)65. As A.D. John (1992)
stated, "in practice, the precise environmental factors to which species may be responding are difficult
to define". As a result, we cannot accurately determine the impact of logging on biodiversity and the
many forest products that draw on this diversity. The implications of our ignorance of species
diversity and tropical ecosystems for natural forest management are clear - we know little, are only
very slowly learning more, and so must err on the side of caution.
Nepsted et al. (1992) describe two types of biotic impoverishment, or ecological degradation, that
result from human use of forest resources: population impoverishment and ecosystem
impoverishment 66 . Ecosystem impoverishment always influences populations, but we do not have
sufficient information to predict the exact nature of these impacts. The harvest of non-timber forest
products, for example of tapir and brazil nuts in the extractive reserve of Porongaba in the Amazon,
could result in population impoverishment, but rarely ecosystem impoverishment. Logging in the
same area can lead to the population impoverishment of roughly 100 tree species and an unknown
number of animal species, and potentially severe ecosystem impoverishment due largely to the 50%
canopy reduction with which logging is associated (Nepstad et aI., 1989).
Gaps in the natural forest created from disturbances such as landslides, earthquakes, rivers switching
course, or individual tree falls are theorized to contribute to species diversity, but gaps created by
logging regimes generally do not result in more diverse forests as a whole (Brown, 1992). In general,
the smaller the scale of disturbance, the more likely local structural, floristic and faunistic diversity
will be temporarily enhanced or remain the same. Larger scale disturbances tend to simplify
ecosystems, which results in a loss of biodiversity both locally and regionally. There is always a
trade-off, then, between the intensity of timber production and the conservation of biodiversity (ITTO,
Draft Guidelines for Biological Diversity Conservation, 1992; Poore and Sayer, 1991).
65 There are exceptions to the rule of high species diversity in tropical forests. Oligarchic forests, dominated by only
one or two tree species, occupy tens of millions of hectares in Amazonia. In many cases, the dominant species produce
fruits, seeds or oils of economic importance. In terms of density and yield, oligarchic forests may rival many of the
commercial fruit plantations in the tropics, and so are a valuable source of non-timber forest products (peters, 1993; Peters
et al., 1989). For example, camu-camu (Myrciaria dubia), a shrub or small tree native to the floodplains of Amazonia,
is often found in large, mono-specific populations; isolated individuals are rarely encountered. In natum! populations,
12,310 individuals/hectare have been found (C. Peters, pers. comm, in Clay and Clement, 1993). Camu-camu fruits
contain one of the highest concentrations of vitamin C in the plant kingdom (2,000-2,994 mg ascorbic acid/lOO g of fruit
pulp), and are widely used locally in juices, ice creams and liqueurs (peters et al., 1989).
66 Population impoverishment results when the genetic diversity or abundance of a population declines as a result of
human activity. Hunting or harvesting practices that favour certain types of animal or plant characteristics or that exceed
the regenerative capacity of the population impoverish the population genetically and structurally. Populations can also
decline as the indirect result of human activity if pollinators or seed dispersal agents are eliminated. Ecosystem
impoverishment results when forest use alters the structural and functional integrity of the forest, changing its ability to
regulate the storage and flow of water, energy, carbon, and mineral nutrients (Nepsted et al., 1992).
39

40
Timber harvesting may not always lead to a reduction in species numbers, but can produce qualitative
changes whereby generalists replace old-growth specialists and a few species come to numerically
dominate 67 (IITO, 1992; John, A.D., 1992; Dahaban, Nordin and Bennett, 1992; Kemp et al., 1993).
Logging damage is essentially random, in that it is spread over all tree taxa. As a result, rare species
are particularly susceptible to the impacts of logging, especially those that are also highly valued
timbers 68 (John, A.D., 1992). Timber species with a limited geographic range, poor dispersal ability,
and few seedlings and saplings in the understorey are generally less equipped to deal with logging
pressures than those widely distributed, with long seed dispersal distances and with numerous
seedlings and saplings in the understorey. Amazonian species such as Swietenia macrophylla,
Vouacapoua americana, Torresia acreana (used locally for medicine and perfume) and Euxylophora
paraensis were found to be susceptible to pressures in the face of intensive logging, while Tabebuia
serratifolia, Hura creptans (exudate used locally for poisons) and Astronium urundeuva (wood used
locally for crafts) might be favoured by changes induced by logging. Most species fell between the
two extremes 69 (Martini et al., 1992). The qualitative changes in forest composition as a result of
logging can promote some timber species used locally for NTFPs, while reducing populations of
others. But most communities rely on a variety and range of forest products to meet their needs and
a reduction in the diversity of available species can have significant repercussions on local
consumption and trading patterns. Similarly, the conservation of biodiversity does not depend upon
the total number of species in a small area, but the number within an entire region. While the
disturbances created by logging, differential species success in varying gap sizes, and the resulting
67 For example, in preliminary studies in unlogged and logged dipterocarp forest in Sarawak, environmental changes
have produced considerable drops in termite species richness, favouring mound-building species over those constructing
simple nests in soil (John, A.D., 1992). Another study in dipterocarp forest in Sarawak demonstrated that following
logging the trend is for edge or colonizer species to replace primary forest species. A number of species appeared that
had never been seen before in the forest, but are common to secondary forests and gardens, such as the plain-tail squirrel
(Callosciurus notatus) and shrews (Tupaia sp.). Those that disappeared after logging were all endangered or totally
protected species or both, such as the clouded leopard (Neofelis nebulosa), sun bear (Helarctos malayanus) and oriental
small-clawed otter (Aonyx conerea) (Dahaban, Nordin, and Bennett, 1992). Stoekdale (pers. comm., 1993) has found that
in 12 year old logged forest in East Kalimantan, populations of the slow-growing, high quality Calamus and Daemonorops
rattan species have been reduced, while the lower value, pioneer-like Korthalsia species have increased in number. This
will obviously have important economic implications for future harvests of rattan in the region.
68 For example, Brazilwood (Caesalpinia echinata) has been eradicated from most of its former range in Amazonian
(John, A.D., 1992). Ceiba pentandra, which has religious importance for many traditional communities, and the seeds
of which are used locally to stuff mattresses and the wood for construction, was extirpated from Iquitos, Peru by intensive
logging operations (Gentry and Vasquez, 1988; Orejuela, 1992).
69 The eight parameters used to evaluate a species' ability to resist the negative impacts of logging include: 1)
effective long-distance dispersal ability; 2) abundance of saplings in the forest regeneration; 3) rapid growth in full sun;
4) ability to resprout; 5) capacity to withstand fire (by virtue of thick bark); 6) broad geographic distribution; 7) even
distribution over the landscape; and 8) high density of adults (Martini et al., 1992).

increases in "edges" can produce localized increases in diversity, it does not increase biodiversity for
the region as a whole 70 (Dahaban, Nordin and Bennett, 1992).
Logging can also impact the survival or density of keystone or pivotal species that control the
structure of the community and help determine which other species are present (WRI et al., 1992).
At Kutai, East Kalimantan, for example, it was found that the "keystone" Ficus species are
significantly associated with some of the major timber species which logging selectively depletes
(Whitmore, 1991)71. In these cases, population impoverishment, as described by Nepstad et al.
(1992), can lead to ecosystem impoverishment, because keystone species are not "redundant" - there
do not exist several other species that perform similar ecosystem functions.
When species are left in small isolated populations they become susceptible to extinction by random
events and genetic deterioration. This, again, is a potentially hidden side-effect of logging operations,
and is particularly important in tropical regions where local endemism is high (John, A.D., 1992).
Heywood and Stuart (1992) state that the loss of genetic variation in species' populations is at least
as important as the loss of entire species, and is the "essence of the process of extinction". Genetic
variation, like soil fertility, can be impossible or extremely slow to rehabilitate through management
schemes. Therefore, fragmentation of forests during logging operations should be kept to a minimum;
logging should be staggered so that various areas are at various stages of succession following
disturbance and mature stands lie in close proximity to each other (WRI et al., 1992). Uncontrolled
selective logging can also eliminate the more desirable genetic characteristics of a timber species by
systematically "creaming" or removing individuals that display valuable traits (Uhl, 1989; Oldfield,
1989; Schmidt, 1991; Clay and Clement, 1993). The intensive collection of fruits from trees that
produce those of the highest quality can similarly result in a population dominated by trees of
marginal economic value (Peters, 1993).
There exists no objective, long-term data on complete logging cycles, so we can only theorize on
impacts over time. Different sites have a wide variation in species abundances and distribution over
even quite small areas, so each forest area must be individually assessed with regards to local species
diversity, endemism and degrees to which logging disturbance produces negative effects. In the short
tenn, studies often demonstrate little decline in species diversity, so long-term studies must be
implemented that detect not only changes in species numbers but in density, as well. The study of
local structural, floral and faunal diversity can be incorporated into permanent sample plots set up
to measure the growth, mortality, and regeneration rates of commercial timber (and non-timber)
species, and other changes in the forest over time (Alder and Synnott, 1992).
70 There is little available information on the effect of disturbance on most species, nor on the relative effects of
shorter and longer felling cycles. (Ashton, pers. comm. in Heywood and Stuan, 1992). Species loss is a logarithmic
function, and so repeated logging, or re-logging before full regeneration of the forest has occurred could lead to severe
and permanent effects on biodiversity (John, A.D., 1992) Many studies which have attempted to detennine the impact
of selective logging or other disturbances on species diversity have produced inconclusive results due to the variety of
factors involved (John, R.D., 1992).
For example, RJ. John (1992) found that in Papua New Guinea he could not adequately detennine the effects of selective
logging on species diversity. He suggests that the major impacts of logging are the physical effects of the removal of logs
and post-logging development of lands made accessible through logging operations.
71 Many of these species are used extensively by local peoples, as well. In the Gunung Leuser National Park, for
example, Ficus species are collected for traditional medical treatments (Sayer, 1991).
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42
The management of natural tropical forests for timber production will inevitably result in a loss of
species and structural diversity, but these forests can form an important component of national landuse
systems that attempt to conserve biodiversity. In no tropical country today will the lands
demarcated as strict nature reserves protect an adequate proportion of that country's biodiversity
(Hansen et al., 1991; Blockhus et al., 1992; WRI et aI., 1992). Forest management for non-timber
products alone is usually more compatible with biodiversity conservation 72 (Salick, 1992; Gomez­
Pompa, 1990). But because a significant proportion of the world's remaining natural forests are
allocated for timber production, the survival of biodiversity depends in large part on the
implementation of natural forest management systems that integrate timber, non-timber products and
conservation objectives.
Because forests are dynamic, they are reasonably robust in their ability to recover from localized and
periodic disturbance. The selective removal of a small volume of timber and non-timber forest
products, followed by management that allows regeneration to occur, can retain a significant portion
of species. The number of species whose populations are critically reduced by logging, and so the
speed with which the original animal and plant communities are reestablished, is related to: the
degree to which the forest is disturbed; the proximity of undisturbed patches which can act as refuges
for mobile species; and the maintenance or return of substantial portions of the forest to the mature
phase structural complexity in which dominance by a few species becomes impossible and diversity
is maintained (IITO, 1992; Reid, 1992; Blockhus et al., 1992; Brown and Brown, 1992, John, A.D.,
1992).
The Impact of Natural Forest Management on Wildlife
Animal-plant relationships are a significant factor in the long-term success of natural forest
management. Regeneration of valuable commercial timber species does not take place in an
ecological vacuum, and is not based solely on the size and frequency with which gaps are opened
during logging operations and the effectiveness of silvicultural treatments. Through predation,
pollination, and seed dispersal, animals play an integral role the regeneration and survival of tree
species.
There exist wide variations in the response of wildlife to changed conditions of habitat and food
supply due to logging. Small, less mobile species are most likely to suffer population reductions as
a result of patchy food sources, and this may affect ranging patterns, breeding success and even gene
flow. Large-bodied, wide-ranging species with generalized diets that may opt for alternative sources
of food will fare best (John, A.D., 1992). Whitmore notes that elephants, rhinoceros, pigs, and other
species that feed generally on lush herbs and shrubs found along valleys and on landslips actually
benefit from the young regrowth along logging tracks, while specialists such as cuckoos, trogans and
many insectivores do not fair as well (Whitmore, 1991). But Dahaban, Nordin and Bennett (1992)
found that in dipterocarp forests in Sarawak the diversity and density ofprimates, squirrels, and other
72 Salick (1992) found that forest under more or less traditional management, although containing fewer species than
primary forest, had higher densities of those species of larger non-timber value, including ipecac and wicker. Selectively
logged forest had fewer species overall and fewer useful non-timber species. Boom (1989) found that the Chacabo Indians
in Bolivia similarly managed forest to increase the proportion of useful species in proximity to their village. High species
dominance is often a reflection of past management activities, including the equivalent of forest gardens, and the
protection and enrichment of valuable species (Gomez-Pompa, 1990).

mammals was severely affected following logging 73 . A.D. John (1991) found in Western Amazonian
that avifaunas in disturbed habitats were dissimilar to that of undisturbed forest to a degree
proportional to the extent of disturbance. Understorey insectivorous birds with specialized foraging
strategies tend to be least able to adjust to conditions of disturbance (John, 1991; Alejandro Grajal,
Wildlife Conservation Society, pers. comm., 1993).
In most tropical countries over 70% of resident vertebrate species are commonly reported to be
dependant upon closed forest, and the figure for invertebrates is probably a great deal higher (John,
A.D., 1992). Invertebrates are far more species-rich than vertebrates and have high microhabitat
specialization, so are likely to be severely affected by logging disturbance, but virtually nothing is
known about them (John, A.D., 1992).
Animals in recently logged forest may face three problems concerning food source trees: fewer trees,
different spatial distribution of trees, and different patterns of fruit and leaf production. The initial
loss during logging of trees used as food sources by wildlife might be buffered by increased levels
of fruiting and new leaf production stimulated by increased light from the opening of the canopy, but
the full range of food sources will not return until the regeneration of primary forest seedlings reach
reproductive maturity (John, A.D., 1992; 1988)74.
Crome (1991) found that while selectively logged forests can provide an excellent habitat for many
species of wildlife, it can threaten specialist frugivorous that are important components of the forest
ecosystem and through dispersal impact the demography of plant species 75 . Uhl (1989) found that
in the Amazon many of the most sought-after timber species produce fruits that are important food
for forest animals. For example, Manilkara huberi, which accounted for 30% of the 1988 timber
volume harvested in Para, has cherry-sized fruits that are consumed by parrots, monkeys, coati, deer
and turtles. A.D. John (1988) found in a West Malaysian dipterocarp forest that residual damage from
logging operations drastically reduced overall availability of food sources for frugivorous and
folivores, even where timber trees are not themselves used by animals.
Post-logging silvicultural treatments can also negatively impact wildlife populations. By promoting
the regeneration of larger proportions of commercial species, poisoning the undesirable, and
"enriching" the forest - often with exotics - silvicultural interventions can alter plant species
composition and destroy species that maintain wildlife populations (Caldecott, 1988; Crome, 1991).
In a study of the commercial species of preference in Queensland Crome (1991) found that the vast
73 Borean gibbons (Hylobates muellerz) decreased by more than 70% in group density after logging. The group density
of maroon langurs (Presbytis rubicunda) dropped about 45% after logging, while that of the white-fronted langurs (P.
frontata) decreased by 35%. Giant squirrels (Ratufa affinis) showed a reduction of 71 % in individual density after logging.
The diversity of species in these areas also decreased markedly. (Dahaban, Nordin, and Bennett, 1992).
74 The uncontrolled collection of non-timber forest product reproductive propagules (fruits, nuts/seeds, and oilseeds)
can also disturb food availability for wildlife. In effect, collectors compete with forest frugivorous, reducing the total
supply of food resources available to ground-foraging animals. Frugivorous might subsequently migrate off-site and
disrupt seed dispersal and seedling establishment for those species whose seeds require scarification by animals to
germinate (peters, 1993).
75 "Legitimate" frugivorous, which digest only the pericarp and void the seeds intact, require fruits of high nutritive
value, are highly specialized and are maintained by a succession of appropriate plant species fruiting sequentially. In lean
periods, they rely on "keystone" species and are highly vulnerable to the loss of a food source (Crome, 1991).
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44
majority of frugivorous rely on uncommercial species, rather than the increasing proportions of highvalue
commercial species with woody fruits and wind dispersed seeds. Silvicultural regimes,
therefore, promoted a decrease in the populations of trees needed during lean times for food.
Enrichment planting of local wild seedlings, such as those recommended by the ITTO, may not
always adequately protect wildlife diversity, although they will undoubtably be an improvement on
planting of exotics 76 (ITTO, Draft Guidelines for Biological Diversity Conservation, 1992). In
Venezuela, enrichment plantings of non-indigenous commercial species in strips were found to
contain 30% fewer species than the surrounding forest; this was less than the number in the logged
over forest left to naturally regenerate (Alejandro Grajal, Wildlife Conservation Society, pers. comm.,
1993).
In Sarawak there is typically a sharp decline in wildlife harvests within ten years of an area first
being logged due to a combination of ecological, social and economic factors 77 : the immediate
physical disturbance resulting from logging; the long-term change in the forest composition and
structure; the influx of timber company workers, many of whom will hunt themselves 78 ; and
improved lines of communication and often additional cash incomes for many rural people. These
factors result in increased hunting pressure as people take advantage of new markets and the access
provided by logging road openings into previously undisturbed forest (Caldecott, 1989; John, R.J.,
1992; Dahaban, Nordin and Bennett, 1992; Wilkie et aI., 1992). Some species are particularly
vulnerable to extermination by hunting, such as rhinoceros, gibbons, bears, leaf monkeys, proboscis
monkeys, clouded leopards and marine turtles (Caldecott, 1988; Dahaban, Nordin and Bennett, 1992).
In this way, the increased opportunities for feeding on herbs along logging tracks suggested by
Whitmore, and the resilience John (1992) suggests primates might show following logging operations,
are off-set by increased hunting pressures (John, A.D., 1986; Redford, 1991; Whitmore, 1991).
In Sarawak, Dahaban, Nordin and Bennett (1992) found that the access provided by logging roads
resulted in a sharp increase in hunting pressures on once remote forest (about 40 km from the nearest
human settlement). Hunting was often carried out from vehicles, and hunters used spotlights at night
to stun animals. In the Republic of Congo, Wilkie et al. (1992) found that the highly selective
logging practised in the concession under study was unlikely to affect faunal populations, but that
the active and passive facilitation providing by logging operations (vehicles, roads, facilities and
company time were often used in support of poaching) increased pressures on wildlife substantially.
76 Although F. Omari (pers. comm. in John, A.D., 1992) found that the impact on food sources for local wildlife was
minimized by the replanting of Calophyllum inophyllum on Zanzibar Island.
77 Hunting in logged areas results in a sharp decline in the estimated wild meat ration per person/year from 54 to 18
g. This effect is exacerbated by a serious decline in riverine fish stocks due to mud and diesel pollution from logging
operations (Caldecott, 1988).
78 In the Neotropics as well, hunting is frequently perfonned by people engaged in forest extraction activities who
are given ammunition but little food, and are expected to hunt to feed themselves. Venezuela et al. (1988) found that in
a watershed near Iquitos, Peru, lumbennen accounted for 51 % ofthe ungulate harvest, illegal commercial hunters for 11 %
and subsistence hunters for only 38% (Redford, 1991).

Many of the most popular game animals are also those which Terborgh refers to as having a
"stabilizing function" and through "indirect effects" maintain the diversity of tropical forests 79
(Terborgh, 1988). In Mexico, Dirzo and Miranda (1990 in Redford) compared two tropical forests,
one with its full compliment of large mammals (peccaries, deer and tapir) and the other in which
these species had been extirpated by hunters. The hunted forest was typified by seedling carpets, piles
of uneaten rotting fruits and seeds, and herbs and seedlings undamaged by mammalian herbivores
(Redford, 1991). Although many important forest animals may not yet be extinct, their populations
may have been reduced to such an extent that they no longer perform their ecological functions SO
(Redford, 1991). A decrease in the number of animals in a forest area can also lead to a number of
more subtle, largely unrecorded, changes within populations. These include changed reproductive
behaviour, sex and age ratios, average body size, patterns in habitat use, and the genetic structure of
a population 81 •
Unfortunately, the pressure to log primary tropical forests is too great to be able to wait for the type
of information needed to determine the ecological mechanisms by which sustainable natural forest
management is possible. In the interim, a compromise must be practised in which indicator species,
coupled with long-term monitoring, allows us to determine a maximum threshold for damage to
wildlife and biodiversity resulting from timber production.
x. Conclusion
In many ways the integration of non-timber and timber products is a new arena of forest
management. Although forest-dwelling peoples have harvested both timber and NTFPs for millennia,
and the harvest of NTFPs often occurs vicariously in recently logged forest or forests managed for
timber production, the industrial, usually capital-intensive forestry practised over the past half a
century, has been almost entirely divorced from non-timber concerns. There has also existed the
perception that what isn't marketed in scale isn't important, and isn't "developed" (Redford, 1991;
FAO, 1991).
As a result, parallel fields of study, literature and academic departments have developed for the same
forests. Ethnobotanists, anthropologists, "social" foresters, and cultural ecologists have a welldeveloped
literature and discussion underway on the role of NTFPs in local forest management.
Foresters, on the other hand, have developed their own plans for the same forests. Rarely will these
professionals interact - rarely will they read the same literature, attend the same conferences, or
collaborate on projects. Lip service is being paid to the integration of the forest sciences and "multi-
79 ttIndirect effects" refer to "the propagation of perturbations through one or more trophic levels in an ecosystem,
so that consequences are felt in organisms that may seem far removed, both ecologically and taxonomically, from the
subjects of perturbation" (Terborgh, 1988).
80 "Ecological extinction tt is defined as "the reduction of a species to such a low abundance that although it is still
present in the community it no longer interacts significantly with other species" (Estes et al., 1989).
81 A.D. Johns (1992) describes changes in hummingbird communities in the neotropics as a result of logging.
Hummingbirds are generally co-adapted with communities of flowering plants, with the different species of hummingbird
diverging in bill shape to exploit corolla design. In the regeneration of logged forest, much available nectar comes from
colonizing shrubs and climbers with flowers of generalized corolla shape. This resulted in the social reorganization of
hummingbird communities to one of aggressive defense of resources (interference competition).
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46
disciplinarytf approaches to forest management, but schemes to integrate non-timber forest products
and multiple-use with timber production are virtually non-existent. As a result, the successful
practical integration of timber and non-timber forest products into natural management of tropical
forests may still be some way off.
In this context, the certification and labelling of tropical timbers from sustainable sources has
emerged. In their efforts to achieve "socially beneficial, economically viable, and environmentally
benign" timber extraction, certifiers and their potential accreditors in the form of the Forest
Stewardship Council, have come to realize that non-timber forest products are an integral component
of sustainable natural forest management (Forest Stewardship, Draft Principles and Criteria, 1993;
Donovan, 1993). As a result, they have made a significant step towards bridging the gap that lies
between the non-timber product sphere of expertise and the timber. In the Draft Principles and
Criteria of the Forest Stewardship Council, for example, "non-timber forest resources must be
inventoried and continued access to such resources by local people incorporated into forest
management" and "research must be conducted on the full range of timber and non-timber forest
products and services found in the forest area, and incorporated into management planning" (FSC,
1993).
Following are some basic suggestions relevant to the integration of non-timber product and timber
forest management. General principles of sound forest management and social and environmental
responsibility, as outlined in the Forest Stewardship Council's Principles and Criteria, the ITIO
Guidelines for the Conservation of Biological Diversity in Forests Managed for Timber and
Guidelinesfor Sustainable Management, and The Smart Wood Certification Program Guidelines, will
not be reiterated here.
It is important that foresters, timber companies and governments do not try to implement integrated
forest management on their own. Collaborations with local, national and international researchers,
NGOs, and development agencies, can bring to the operation a knowledge of local forests, species,
NTFPs, and people that will compliment that of the timber specialists.
NTFPs should not be an add-on, randomly attached to established management plans. Inventories
of species, assessments of their social and economic value to local people, and a rough estimate
of existing trade patterns, must be quantified in some way prior to the setting of management
objectives (De beer and McDermott (1989), for example, provide a list of quantifiable indicators
of the economic value of NTFPs to rural people).
Similarly, local people should not be "consulted tf regarding an existing management plan, but
should be integrated into the process by which priorities and objectives are set and decisions
made. This process not only acts as a catalyst by which various interest groups can imagine and
formulate various futures, but when completed it serves as a contract setting out the
responsibilities of the local users and the company/government (Berkes et al., 1991). Likewise,
the practical management of forest resources should involve the active participation of local
people, and their responsibility for the overall venture should be significant.
The market values of NTFPs should be included in any financial analysis of forest management.
Ethnobotanical literature on the region in which harvesting operations are to take place should
be consulted. Traditional uses of species recorded in this literature can provide an idea of the

ange of products contained in the forest, and traditional management practices (such as
management of fallows) can provide important "headstarts" in the design of appropriate
silvicultural regimes.
Harvesting operations should be staggered so that various areas are at various stages of
succession following disturbance and mature stands lie close to each other (WRI et al., 1992).
By minimizing fragmentation, greater species diversity is maintained, and the likelihood of loss
of NTFP species minimized.
Refuges (composing 5-20% of the forest area), representing all forest types and particularly those
with high species diversity and endemism, and corridors should be left between forest patches.
Areas with unusual land fonns, geology or other physical features should be protected. Major
saltlicks, feeding grounds, and other features which maintain particular wildlife populations
should be preserved. Tree taxa that are important food sources for wild animals should be
protected from harm during the logging operation and subsequent silvicultural regimes. Hunting
by timber company employees or non-locals should be prohibited. Wildlife populations should
be continuously monitored (Caldecott, 1988, Crome, 1991; John, A.D., 1992; ITIO Guidelines,
1992).
In addition to refuges established primarily to maintain wildlife and species diversity, areas
containing significant numbers of non-timber forest product species should be avoided by logging
operations (Lamb, 1991). Incentives and disincentives should be provided to loggers to insure
that these measures are adequately carried out.
Local communities should work with forest managers to design a schedule for logging operations
that compliments their needs for employment, and incorporates the pre- and post-logging harvest
of NTFPs. The planning of roads and skid trails should include provisions to not disrupt and
perhaps facilitate the harvesting and transport of NTFPs.
Silvicultural systems should not drastically alter the structural or species diversity of the forest.
Enrichment plantings should be of native species, and should include multi-purpose species.
The ecological sustainability of all NTFPs should be assessed, as far as is feasible, based on the
plant part used, the floristic composition of the forest, the nature and intensity of harvesting, and
the particular species or type of resource under exploitation (Peters, 1993), and should be
monitored through a system of permanent sample plots.
A diversity of non-timber forest products should be extracted from the forest to produce a system
with seasonally complimentary harvests, and with reduced vulnerability to fluctuations in market
demand for a particular product (Padoch et al., 1992; Reining and Heinzman, 1992; Phillips,
1992).
Where appropriate, local, regional and international NGOs should be enlisted to assist with the
selection of species and development and expansion of external markets for a diversity of
products (Clay, 1992; Ziffer, 1992; Clay and Clement, 1993; Gentry, 1992). Where demand could
exceed the capacity of existing harvesting systems to supply the market, alternative systems
(including domestication of important species outside the forest area by local communities), must
be employed (Cunningham, 1991).
47

48
The primary importance of non-timber forest products for subsistence and local markets should
not be superseded by international demand for any NTFP product.
Expropriation of resource use rights by powerful elites within these regions should be actively
denied.
The traditionally lopsided distribution of income from NTFPs - that is, the inverse relationship
between the effort expended to produce a product and the income received - should be altered
by the development or promotion of cooperatives, value-added processing and more equitable
distribution of income along the chain of producers and marketers. The successful incorporation
of NTFP extraction into forest management should not be dependent upon the physical and
economic privation of extractors (Sizer, 1992; Browder, 1992).
Traditional systems of resource management and regulation of harvesting should be employed,
or their remnants built upon, to control resource extraction in the forest. Policing the removal of
NTFPs by local people is not a viable option. Collection of NTFPs by non-locals, however,
should be discouraged, and methods employed devised by local communities.
The long-tenn ownership and control of forest resources should clearly rest in the hands of local
communities. In addition to the obvious ethical justification for land tenure, sustainable
production is more likely to result from secure tenure in systems where the long-tenn, lowintensity
harvesting ofspecies from high-diversity forests can prove difficult and time-consuming.
The nature and scale of timber harvesting operations should be adjusted to fit in with the existing
NTFP harvest and trade patterns of local communities in cases where these are well-developed.
Timber extraction should be seen as a compliment to these activities, rather than the primary
objective of forest management.

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