A review of dipterocarps - Center for International Forestry Research

Plantations
G. Weinland
Introduction
Research on establishment and maintenance of
dipterocarp plantations has been pursued now for almost
seventy years. Efforts were especially intensive in three
countries: India, Indonesia and Malaysia. In India the
research concentrated mainly on Shorea robusta because
of its abundance and its significance for agroforestry
systems. In Indonesia and Malaysia and some other
countries of the Indo-Malayan region a wider range of
dipterocarp species was investigated. The research
covered the whole range of plantation problems, albeit
not with the same species over the whole range. Probably
with exception of S. robusta no other dipterocarp species
has been so well studied for operational schemes. On the
whole, young dipterocarp plants were considered
sensitive, delicate, and unsuitable for even-aged
plantations but appropriate for enrichment planting. The
fear of over-exposing sensitive young dipterocarp plants
to light, however, has led to frequent failures of planting
operations. It was thought that the young plants needed
overhead shade for survival and good growth. The wide
tolerance variation among different dipterocarp species,
and their changes with age, were not recognised.
In India, the earliest plantation efforts recorded are
for Shorea robusta in 1860 at Barielly in Uttar Pradesh
and Hopea parviflora in 1880 in South Kanara, Karnataka.
Hopea was underplanted in teak plantations as a possible
second storey crop in the coastal plains. Around 1890,
taungya systems were started in West Bengal and Uttar
Pradesh. This still continues, but on a reduced scale as
there is progressively less and less clear-felling of forests.
In Uttar Pradesh the main dipterocarp species was S.
robusta, while in West Bengal, which has a more humid
climate with less seasonality of rainfall, S. robusta was
mixed with Chukrassia tabularis and Michelia champaca.
The practice was to sow seeds in lines. Around 1910,
Hopea parviflora, Dipterocarpus turbinatus and Vateria
indica were raised in a clear-felled area in Makut
Chapter 9
(Karnataka). In South Kanara district, the home of five
Hopea spp., techniques for raising H. parviflora and H.
wightiana were already perfected by this time. The two
species are raised together in private woodlots by local
people, H. parviflora for timber and poles and H.
wightiana for fuel wood. Currently, all these species are
being planted for restoration of degraded rain forests and
re-afforestation of barren land. The nursery techniques
for some of these species have been standardised (Rai
1983) and experimental results on restoration of degraded
rain forests have been reported (Rai 1990). In the
Andaman Islands, the Andaman Canopy Lifting System
was developed to secure the regeneration of dipterocarp
species (Chengappa 1944). To ensure regeneration of
Dipterocarpus macrocarpus in North East India, a system
called Aided Natural Regeneration involving
supplementary planting of dipterocarps, is popular.
Dipterocarp plantation research or research with relevance
to dipterocarps covered a very wide range. The majority
of the research was devoted to Shorea robusta. Aspects
especially investigated were seed procurement/production
and germination (e.g., Verma and Sharma 1978, Rai 1983,
Prasad and Parvez-Jalil 1987), soils and nutrition (e.g.,
Bhatnagar 1978), rehabilitation of degraded sites (e.g.,
Prasad 1988, Rai 1990), pests and diseases (e.g., Harsh
et al. 1989, Sen-Sarma and Thakur 1986) and agroforestry
(e.g., Jha et al. 1991). In situ gene conservation of Vateria
indica is carried out in the Western Ghats (Negi 1994).
Troup’s Indian Silviculture (1980) gives a full account
of silviculture in India and Burma and contains in the
second volume the complete silviculture of sal (Shorea
robusta) including plantation silviculture. Additionally,
it contains the silvicultural characteristics of the following
dipterocarp species: Shorea assamica, S. talura (syn.
roxburghii), S. tumbuggaia, Dipterocarpus alatus, D.
bourdilloni, D. costatus, D. grandiflorus, D. indicus (syn.
turbinatus), D. kerrii, D. macrocarpus, D. pilosus, D.
tuberculatus, D. turbinatus, Hopea glabra, H. odorata,
H. parviflora, H. utilis, H. wightiana, Vateria