Bwa-yo - Société Audubon Haiti

124 Lisina ...Delen
Figure 15.6 Leucaena fodder banks are an
excellent source of nutrition to complement
food rations of goats and other livestock.
desirable genotypes. Efforts to maintain
the genetic vigor of the hedgerows with
improved glabrata varieties must be
ensured with isolated and secure seed
orchards.
A variety of container types have
been used to propagate the species, the
most appropriate being a function of
nursery costs. Rootrainer and Winstrips
were utilized during most of the 1980s
in Haiti, though ODH utilized a much
smaller Styrofoam SpeedJing tray for
seedlings planted on fertile land.
Manual scarification, by nicking the
cotyledon end of the seed, is recommended
for research and experimental
seed lots; immersion in hot water, at
least 49° C, followed by a 2-day soak, is
the method most often used for mass
propagation purposes. Inoculation by
Rhizobium, either coating the seed or
drenching the sown seed, is a safeguard
for insufficient field inoculum.
Inoculation procedures are recommended following pesticide applications for psyllid
and root rot attacks. Generally 14 weeks is sufficient to raise seedlings, with an initial
3 weeks of shade and a final 4 weeks of hardening off. Psyllid (H. cubana) (Fig. 15.7),
damping off and root rot diseases (Pythium, Rhizoctonia, Phytophtora, Alternaria,
Fusarium, Myrothecium) have been observed to attack nursery seedlings (Tourigny,
1987; Runion et aI., 1990). The species can be top-pruned, if necessary, prior to outplanting.
Stump propagation and vegetative methods, including root cuttings and tissue culture
have not been experimented in Haiti, though these have been reported from other
countries and are examined in Pound and Martinez (1984).
Biomass Studies: Regression equations to estimate the biomass of subspecies glabrata
were conducted at four sites for 5-7-year-old trees and once for a 2-year-old coppice
rotation. These equations a]Jow one to estimate various tree dry weights based on easily
measured stem and height measurements. There is a significant difference in the coefficients
between coppice and seedling rotations because of the difference in stem and
canopy forms, with the coppice stem concentrating a much greater amount of the total
tree weight as polewood rather than as fuelwood. The differences in estimates among the
equations for the standards (i.e., seedling rotation) are mainly because of the differences
in sampling distribution rather than differences in form. A summary of the biomass
equations is provided in Table 15.2.
Charcoal and Lumber Conversion Rates: When 3-4-year-old L. leucocephala is converted
to charcoal, only about 17-20% of the wood dry weight becomes merchantable