BOMBAX FAMILY (BOMBACACEAE) 



Key to the 3 native species, all illustrated (Nos. 153-155) 



A. Leaves digitate (palmate), with 5-S lance-shaped or oblong leaflets — 153. C'eiba pentandra. 

 AA. Leaves simple. 



B. Leaves with 5-9 main veins from base — 154. Ochroma pyramidale. 

 BB. Leaves with 1 main vein or midrib — 155. Qiiararibaea iurbinata. 



153. Ceiba, silk-cotton-tree 



Ceiba pentandra (L.) Gaertn. 



This giant tree, one of the lai'gest m tropical 

 America, is easily recognized by the massive gray- 

 green or gray smoothisli trunk ( spiny when small) 

 which reaches an enormous size of 5-8 feet or more 

 in diameter above the unusually large narrow but- 

 tresses and by the very broad flat crown of hori- 

 zontal branches. Other distinguishing character- 

 istics are: (1) the palmately compound leaves 

 (digitate) of 5-8 lance-shaped or oblong leaflets 

 3-8 inches long, drooping from the end of a long 

 petiole; (2) numerous spreading 5-parted whitish 

 to pink flowers 11/4-11/2 inches long and broad ; and 

 (3) oblong or elliptic seed capsules 3-6 inches or 

 more in length and 2 inches in diameter, contain- 

 ing many seeds and woolly hairs, the kapok of 

 commerce. 



Ceiba is a rapidly growing deciduous tre« be- 

 coming 80 feet or more in height. The buttresses, 

 6-12 inches thick, extend horizontally out from 

 the tnuik over the large roots as much as 10 feet 

 and almost as high. Many stout conical spines 

 i/g-l inch long are present on branches and small 

 trunks but are. mostly absent on large tnuiks. The 

 thick inner bark is light brown and almost taste- 

 less. The thin crown is commonly broader than 

 the height of tlie tree. Twigs are stout, green at 

 tip, and becoming gray. 



Leaves are alternate, with slender green petioles 

 3-9 inches long. The leaflets hang clown on short, 

 stalks V8-% inch long and are 3-8 inches long and 

 %-l% inches broad, short-pointed at base and 

 apex, not toothed on edges, thin, above bright 

 green to dark gre«n, and beneath dull green. 



Great quantities of flowers are produced in la- 

 teral clusters near the ends of twigs in winter or 

 early spring (December to February) though not 

 every year, often while the tree is leafless. Flower 

 stalks are l-li/^ inches long. The calyx is cup- 

 shaped, about 1/2 inch long and broad, with 5-10 

 shallow teeth. The 5 petals are about IV4 inches 

 long, whitish to rose colored, and densely brown 

 silky hairy on the outer surface. Five stamens, 

 longer than the petals, are united into a column 

 near the base. The pistil consists of 5-celled ovarj- , 

 a long style curved near apex, and enlarged stigma. 



Seed capsules mature in spring and summer, 

 splitting open along 5 lines. Many rounded black 

 seeds less than % inch long (about 3,200 to a 

 pound) are imbedded in a dense mass of gray 

 woolly hairs. 



The wood is very light brown but nearly al- 

 ways turned to blue gray by sap-staining fungi, 



the sapwood almost the same color and not readily 

 distinguished. It is very soft, exceedingly light- 

 weight (specific gravity 0.23), weak, coarse-tex- 

 tured, and straight -grained. The rate of air-sea- 

 soning and amount of degrade are moderate. The 

 wood machines easily but not satisfactorily. Ma- 

 chining characteristics are as follows: planing, 

 sanding, and resistance to screw splitting are ex- 

 cellent; shaping and boring are poor; turning is 

 very poor; and mortising is fair. Logs and lum- 

 ber are very susceptible to attack by insects and de- 

 cay. However, blue-stain can be prevented by dip- 

 ping the lumber in a fungicide solution soon after 

 sawing. 



The wood is seldom used in Puerto Rico al- 

 though sometimes has served for interior sheath- 

 ing. It resembles heavier grades of balsa 

 (guano) but is twice as strong and could be used 

 similarly. It is suitable for boxes, slack cooper- 

 age, toys, light construction, patternmaking, and 

 utility-grade plywood. Because it is easily worked 

 and in spite of lack of durability, the wood has 

 been employed for tubs and basins. Indians made 

 drums of the wood and hollowed out the trunks 

 for dugout canoes of large size. 



Trees are occasionally planted for shade and 

 ornament, and young cut branches or cuttings will 

 root when planted. In many tropical towns a 

 giant spreading ceiba occupies the center of the 

 plaza. Classed as a valuable honey plant. It is 

 repotted that the leaves are edible when cooked. 



Kapok, the woolly or silky hair from the seed 

 pods, is an important product of this species. The 

 harvest is mainly from planted trees in Java and 

 the Philippines. A growing tree produces about 

 600-900 seed capsules or 6-9 pounds of clean floss 

 annually. This fiber is fine, lightweight, and elas- 

 tic and does not become matted vmder pressure. 

 Because of these characteristics and its insulating 

 qualities, kapok is preferred for linings of sleep- 

 ing bags and was a strategic material in the last 

 war. Another use is for life preservers. In many 

 places kapok has been used locally in stuffing pil- 

 lows and mattresses, and commercial development 

 has been su.crgested where the trees are sufficiently 

 common. The fiber is brittle and inflammable and 

 not suitable for spinning into threads. An oil 

 suitable for making soap and illumination has been 

 extracted from the seeds. 



Ceiba is .scattered and widely distributed in 

 Puerto Rico along river banks and open hillsides 

 on the coastal plain and in the lower mountain 



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