Flora of Dominica, Part 2 - Smithsonian Institution Libraries

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secondary forest, noting it has been reduced by man and is not
a climax community. Hodge notes diverse components as
Pithecellobiurn jupunba (bois cicerou), Swartzia simplex
(z'oranger), Andira inermis (angelin), Cedrela odorata (acajou),
Myrcia splendens ('ti feuille), Daphnopsis caribaea (bois
piment), Byrsonima spicata (bois tan), Calophyllum antillanum
(galba), Buchenavia tetraphylla (z'olivier), and a fern, Blechnum
occidentale, here a dominant.
Hodge's key separates a Semi-Evergreen Seasonal Forest
from the true Deciduous Forest, noting that the former has trees
in three strata with less than 1/3 of the top stratum being
deciduous. The latter has trees in only two strata with more than
l/3 of the top stratum being deciduous.
5. RaiMorest Proper: This is the most luxuriant and
extensive of all forests on Dominica, lying roughly at
1000-2500 ft (305-762 m). The luxuriance is the result of
abundant rain averaging from 175 inches or 440 cm (Sylvania)
to 300 inches or 760 cm (Laudat). Much of the soil is a heavy
red earth underlaid by an impervious hardpan, reflected by the
shallow root systems of the trees. The forest floor is quite open
and easy to traverse, except for the exposed root systems of the
big trees. The canopy is usually closed overhead by the highest
trees, -100 ft (30 m). Beneath them is a layer of medium trees
40-80 ft (12-24 m) tall. A lower stratum of small trees 15-40
ft tall comes next. The bottom stratum is of herbs and shrubs,
often dominated by suppressed (low light conditions) seedlings
of the trees.
Among the common canopy trees are Dacryodes excelsa
(bois gommier), Sloanea caribaea (chataignier 'ti feuille),
Sloanea dentata (chataignier grande feuille), Talauma dodecapetala
(bois pin), Ormosia monosperma (caconier), Pouteria
semecarpifolia (contrevent), Chimarrhis cymosa (bois riviere),
and Dussia martinicensis (pommier). The forest is sometimes
called a Sloanea-Dacryodes association after its most conspicuous
dominants.
Among the trees of second stratum are Tapura antillana
(bois cote), Amanoa caribaea (carapite), Sterculia caribaea
(mahot cochon), Licania ternatensis (bois diable), Symplocos
martinicensis (graines bleues), Richeria grandis (bois bande),
Guatteria caribaea (bois violin), and Inga ingoides (pois doux
marron). The bois diable, so called because of its hard wood, is
much sought for making the finest charcoal.
Among the trees of the third stratum are Chrysophyllum
argenteum (bouis), Faramea occidentalis (cafe marron), Ixora
ferrea (bois pichette), Marila racemosa (cachiman falaise),
Heisteria coccinea (bois perdrix), and Cordia laevigata (coco
poule).
The shrubs of the lowest stratum include common and
showy Palicourea crocea, Psychotria uliginosa, Psychotria
urbaniana (including Cephaelis swartziz), and Stylogyne
canaliculata. Ferns abound (including a spiny tree-fern,
Cyathea muricata, often supporting colonies of the filmy fern,
Trichomanes polypodioides) and terrestrial orchids are to be
found.
There are many lianas, often difficult to identify because
their leaves and flowers are high in the canopy. Among these
are Marcgravia, Hillia parasitica, and Blakea pulverulenta,
Epiphytes are abundant, also often out-of-reach, if not
out-of-sight. One interesting one is Clusia major (kaklin),
which begins as a epiphyte and sends down strong roots that
eventually can strangle the host.
In some poorly drained areas at higher elevations one finds
stands of stilt-rooted trees known as mang, Tovomita plumieri
(mang rouge) and Symphonia globulifera (mang blanc).
When the rainforest canopy is opened by tree falls many
species of forest edges and river banks move in. Among these
are cre-cre (many species of melastomes, including Miconia
and Conostegia), Inga laurina (pois doux), Inga ingoides @is
doux marron), Cecropia peltata (bois canon), Simarouba
amara (bois blanc), and Chimarrhis cymosa (bois riviere).
The commonest shrubs include white-spiked Gonzalugunia
hirsuta (bois cabrit), Palicourea crocea (with yellow flowers
on showy red pedicels), and magenta-flowered Odontonema
nitidum (bois crapaud), Piper (doctor bush), and Psidium
guava (guava).
Weedy herbs include Ageratum conyzoides, Emilia sonchifo -
lia, Bidens, Desmodium, Stachytarpheta, and Alternanthera.
Razor-grass (Scleria secans) can make impenetrable thickets.
On bare slopes are several ferns, scrambling Dicranopteris
bijida, Cyathea arborea (a weedy tree-fern), Lycopodium
cernuum (club-moss), and the gold-fern (Pityrogramma
calomelanos).
6. Montane Rainforest: This community forms a transition
from the midland Rainforest proper and the Elfin Woodland of
windswept summits. It occurs on or near exposed mountain
ridges or summits of lesser peaks. One of the characteristic
species is Cyrilla racemiflora (bois rouge). Tree trunks are
mossy but otherwise free of epiphytes. The dominant trees are
Podocarpus coriaceus (raisinier montagne) and Richeria
grandis (bois bande). Prominent species cited by Hodge are
Byrsonima trinitensis (mauricif), Tovomita plumieri (mang
rouge), and Ilex macfadyenii ('ti citron). A fiercely spiny fern,
Cyathea imrayana, is a hazard to the stumbling botanist
reaching for support.
Hodge's key differentiates the Lower Montane Rainforest,
with dominant trees -30 m tall, from the true Montane Forest,
with dominant trees -20 m tall.
7. E@n Woodland: This is a low, impenetrable thicket-like
forest in which the leaves, branches, and tree trunks are covered
with epiphyllous hepatics and dripping mats of mosses,
sometimes called a Cloud Forest or Mossy Forest. It occurs on
the summits and upper slopes of the highest mountains and is
well-developed on the summits of Diablotins and Trois Pitons.
On slopes one must climb through the trees and on the summits
the woodland is virtually impassable without a path unless one
can walk on upper branches.
The Elfin Woodland probably has more species that are
endemic or have extremely restricted distributions than any