Important Trees of Haiti

112 Kasya
and the sandstone-derived soils of the Plateau Central as well as basaltic soils.
Seedlings and coppice shoots are shade tolerant and exhibit a yellowish-green growth
under its own deep shade. The species prefers to grow in full light and caphlres the site
to the exclusion of other species once it is established. However, it is not as aggressive
as other fast-growing species, with a much lower rate of natural seeding than Leucaena
and Azadirachta indica.
Tree Characteristics: The tree rarely grows taller than 18 m in Haiti, having stems that
range from a low-forking bole to a single main stem that may reach to 10m, partiClIlarly
in pure stands (Fig. 14.2). Stem form appears to be sensitive to soil conditions;
scattered stands of excellent form occasionally are seen throughout Haiti, mainly on
basaltic and sandy loams. Multiple and low-forking stems require early pruning to
develop straight wood for construction purposes. The tree coppices well in partial
shade; boundary and fence trees can be pol larded for fuelwood and light management
for understory crops. Crown diameters extend up to 8 m, with an average crown
width:DBH ratio of 29.6. Peak fruiting occurs around December, but seed is available
between October and February and again during April and May. There are approximately
30,000-40,000 seeds kg· l •
Wood density is moderate, ranging from 0.57-0.83 for samples taken from 5-yearold
trees in the Northwest. The dark brown-black heartwood ofS. siamea is streaked and
hard, while the sapwood is light brown and moderately hard, but not durable.
Utilization: S. siamea traditionally was planted as an ornamental and shade tree in areas
of southeast Asia where it is native. It forms a good windbreak with a closed and erect
crown. In Haiti, it has become a general-purpose tree, providing a quick source ofwood
for construction material and fuelwood
(Fig. 14.3 and Fig. 14.4). The
bark is used as a source of tannin. It is
not a preferred browse species and is
reported to be toxic to pigs. However,
ruminants can eat it as part of the diet
(Geilfus, 1989). As a fodder, it generally
is planted along the garden
boundary and lopped as required. The
proximate analysis is shown in Table
14.1.
The wood is susceptible to decay
and termite attack, with 60% of
untreated posts tested in Puerto Rico
considered unserviceable after 1 year
(Englerth, 1960). The grain is interlocked,
but takes a good polish and is
acceptable for turnery. Charcoal
made from the wood is considered
Figure 14.2 Five-year-old S. siamea provenance
trial at Mirebalais.
medium grade and inferior to
Prosopis. Acacia and Casuarina