Common Trees of Puerto Rico and the Virgin Islands

LEGUME FAMILY (LEGUMINOSAE)
Key to the 3 subfamilies
A. Flowers regular, with 10 to many long, spreading stamens, separate or united at base; petals meeting by edges
in bud: leaves bipinnate (pinnate in Infla)-Qlimosn Subfnmily (hfimosoideae; Mimosaceae), this page below.
AA. Flowers irregular, with 10 or fewer stamens, often united ; petals overlapping in bud.
B. Flowers only slightly irregular; the 5 petals separate, the largest petal innermost in bud; leaves pinnate or
bipinnate, sometimes of 2 leaflets or simpl+Cassia Subfamily (Caesalpinioideae; Caesalpiniaceae),
page 168.
BB. Flowers very irregular, beanlike or butterfly-shaped; the 5 petals being the standard (largest and o~~termost
in bud), 2 wings, and 2 slightly united forming the keel ; leaves pinnate, sometimes of 3 leaflets-Pea Sub-
family (Lotoideae ; Fabaceae) , page 188.
MIMOSA SUBFAMILY (MIMOSOIDEAE; MIMOSACEAE)
Key to the 13 species illustrated (Nos. 58-70)
A. Leaves pinnate. the leaflets in pairs.
B. Leaf axis winged ; leaflets hairy ; pods nearly cylindrical, 4-angled-*. Inga Vera.
BB. Leaf axis cylindrical, not winged : leaflets hairless or nearly so; pods flattened.
C. Leaflets 4 (sometimes only 2) -02. Inga laarina.
CC. Leaflets usually 6 or 8 (sometimes 4)--03. Inga quatcmata.*
AA. Leaves bipinnate.
D. Leaflets very narrow, less than 1h inch wide, relatively long.
E. Twigs with paired spines at nodes ; lateral axes (pinnae) 14.
F. Lateral axes 1 or sometimes 2 pairs, each with 12-25 pairs of leaflets 34-% inch long; spines brown
or gmy-70. Prosopir frc.liflora.*
FF. Lateral axes 2-6 pairs, each with 15-26; pairs of leaflets 4 946 inch long; spines whitish-58. Acacia
farnesiana.*
EE. Wigs not spiny ; lateral axes (pinnae) 3 to many pairs.
Q. Lateral axes no more than 10 pairs.
H. Lateral axes 3-10 pairs, each with 10-20 pair8 of my-green leaflets %o-% inch long--65. Leucaena
glauca.
HH. Lateral axes 8-10 pairs, each with 2040 pairs of shiny, dark green leaflets $d inch Iong-07.
Pithecellobiurn arboreutn.
GG. Lateral axes 20-35 pairs, each with 30-100 pairs of minute leaflets % inch or less in length--88.
Piptadenia peregritta.
DD. Leaflets more than inch broad, less than 4 times as long as broad.
I. Leaflets 2 palrs-68. Pitkecellobium dztlee.*
11. Leaflets many, lateral axes (pinnae) 2-7 pairs.
J. Leaflets slightly diamond-shaped, asymmetrical-69. Pithecellobiurn suman.*
JJ. Leaflets oblong, rounded at apex.
K. Leaflets oblique or asymmetrical at base.
L. Lateral axes W pairs, each with 4-9 pairs of leaflets %-I% inches long; the flat pods straw-
colored, more than 1 inch brond-60. Albizla lebbck.*
LL. Lateral axes 4-7 pairs, each with 6-14 pairs of leaflets; the flat pods rich red, turning to
brown, less than incli broad-01. Albizia procera.*
KK. Leaflets symmetrical, rounded at both ends, with tiny point at apex--60. Adenanthertz pavunina.*
58. Aroma, sweet acacia Acacia farnesiana (L.) Willd.*
A spiny shrub or small tree of dry areas, char- gland. The thin p en leaflets sometimes as much
acterized by : (1) the conspicuous paired whitish as 16/16 inch long are short-pointed at apex, rounded
spines (stipules) at nodes on the slightly zigzag at base, and hairless or sometimes hairy around
twigs; (2) tmice pinnate (bipinnate) leaves 2-4 edges.
inches long, with 2-6 pairs of lateral axes (pin- Flower heads are borne 1-3 together on hairy
nae), each with 10-25 pairs of narrow (linear or stalks 34-1% inches long and composed of numeroblong)
stslkless leaflets 4/s"9/16 inch long; (3) very ous narrow flowers about 1/4 inch long ending in
fiagmnt flowers in bright yellow balls (heads) vov man yellow threadlike stamens. Tlle tubuabout
y2 inch wross the numerous stamens on ltlr 5-toot T' led calyx is x6 inch long; the tubular
lateral stalks; and (4) dark brown to blachsh S-toothed comlla is % inch long; them are mpy
pods 1v23 inches long and 3/8-1/2 inch broad, thmadlike stamens almost inch long; and plstil
straight or slightly curved, 1-3 on a stalk.
3 / 1 ~ inch long of narrow ovary and slender style.
A deciduo~is sl~rub ust~ally less than 10 feet high The pods are thick and only slightly flattened
or sometimes a small tree, much branched and wlcl only a little narro~vecl between the seeds,
spreading. The bark is dark brown and srnooth- contain sweetish pulp, and open lab. There are
ish. The twigs are dark brown with light colored sevoml brown seeds, elli tic and sli htly flattened,
dots (lenticels) and with paired spines 4/s-% inch 956 inch long. Recorde B in flower F rom November
or more in length.
to February. The ftwits remain attached after
Often the alternate leaves are crowded on short, maturing.
spur twigs and appear h be inore than 1 at s The sapwood is yellowish and the heartwood
node. The slender hairy axis bears n. minute round roddish brown. The mood is hard and heavy
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