MULBERRY FAMILY (MORACEAE) 



20. Yagrumbo hembra, trumpet-tree 



One of the. most abundant trees in Pnerto Kico, 

 this species is easil}' recognized by : (1) a very thin 

 spreading crown of a few stont brandies arising 

 high on the trnnk and curving upward; (2) the 

 few very large thick unibrellalike (peltate) leaves 

 with l)lades 1-21/2 feet across, composed of 7-11 

 large lobes spreading at the end of a stont petiole 

 almost as long; (.'5) the whitish or silvery under- 

 surface of leaves readily seen when nptunied by 

 a breeze; and (4) the newer branches liollow ex- 

 cept for partitions at the nodes. 



A medium-sized evergreen tree to 70 feet high 

 and 2 feet in trunk diameter, deciduous in areas 

 witli a pronounced dry season. Sometimes de- 

 veloping prop roots around the base. The gray 

 bark is smootli and tliin, witli narrow rings and 

 large leaf .scars at the nodes or joints 2— i inches 

 apart. Inner bark is pinkish and slightly bitter, 

 with watery latex. The smallest branches are ll^ 

 inches in diameter, green and slightly liairy at 

 apex, becoming gray, with rings at nodes. There 

 is a giant bud covered by a large, pointed, reddish, 

 hairy scale (stipule) 5-10 inches long. 



Leaves are alternate but clustered at ends of 

 branches, each on a stout round green petiole 12-20 

 inches long, enlarged at base. The leaf blades, 

 rounded in outline, have 7-11 lobes and veins ra- 

 diating from the end of the petiole (palmate), the 

 lobes and sinuses rounded. Upper surface is 

 green, slightly rougli. and hairless, and lower sui-- 

 face with a dense coat of wiiitish hairs. 



Male and female flowers are on diffei-ent trees 

 (dioecious) in paired fingerlike clusters at leaf 

 bases. Male flower clusters have a stalk 2-3 inches 

 long bearing aliout 15 narrowly cylindrical pale 

 yellow branches (spikes) 2-3 Vo inches long and 

 %6 inch in diameter, each on a stalk V^-Vo inch 

 long. The very numerous, tiny, crowded male 

 flowers are Vie inch long and narrow and have a 

 tubular calyx and 2 stamens. 



Female flower clustere on stalks 2-3 inches long 

 consist of 2-5 stalkless, thicker, cylindrical, gray 

 branches (spikes). The minute female flowers 

 more than Vjg inch long, sunken in the axis, are 

 composed of a tubidar calyx enclosing ovary and 

 style and an exposed finely branched stigma. At 

 maturity the branches (multiple fruits) are 2i/4-i 

 inches long and %-V2 inch in diameter, gray and 

 slightly fleshy, dotted with many l-seedecl minute 

 fruits (about" 2,200,000 to the pou'nd). The numer- 

 ous l)rown seeds are more than t'lg inch long. In 

 flower and fniit probably through the year. 



The wood is whitish, liglit weight (specific grav- 

 ity 0.29), soft, weak, and lirittle, tjut tough for its 

 weight. It is not durable and is very susceptible 

 to attack by dry-wood tennites. Unlike the hollow 

 branches, the main trunk is solid. The rate of air- 

 seasoning is rapid, and amount of degrade is con- 



Cecropia peltata L. 



siderable. Machining characteristics are as fol- 

 lows: planing and sanding are good; shaping and 

 turning are fair; boring is very poor; mortising is 

 poor; and resistance to screw splitting is excellent. 



In Puerto Rico the wood is used for manufac- 

 ture of excelsior. Combined with cement, it is 

 made into a type of insulation board for light in- 

 terior construction and partitions. The wood 

 should be a suitable substitute for balsa in manu- 

 facture of toys, models, and other pi-oducts made 

 from moderately heavy grades of balsa. Else- 

 where the wood has been used for matchsticks, 

 boxes and crates, interior boarding, and paper 

 pulp. 



The liollow stems liave been used to make floats 

 for fishnets and life ])reservers and, when split in 

 two, have served as water troughs and guttei-s. 

 Substitutes for cork stoppers have been whittled 

 from the soft wood. In some countries the leaves, 

 bark, aiul latex have been employed in local medi- 

 cine. The fibrous bark of I'elated species was used 

 by Indians for cordage and mats. It is reported 

 that the wood ignites easily from friction and 

 serves as tinder. 



Hollow branches of this and related species else- 

 where are inhabited by small stinging ants which 

 bore holes to reach the interior. Early naturalists 

 obsei-ving this constant association imagined that 

 (lie ants, as payment for the residence furnished, 

 weie aggressive in diiving away insects or other 

 natural enemies threatening the tree. However, 

 in Puerto Rico ants are not associated with this 

 species, and the trees thrive. 



Abundant in open areas and in forests both vir- 

 gin and cutover. throughout Puerto Rico with the 

 exce])tion of parts of the dry coastal and dry lime- 

 stone regions. Also in Vieques, St. Croix, St. 

 Tliomas, St. John, and Tortola. 



The trees propagate naturally and at first grow 

 very ra]iidly (2-3 inches in diameter per year) but 

 require nearly full sunlight. The seeds appar- 

 ently germinate slowly. In Trinidad it was ob- 

 ser\ed that bats eat quantities of the succulent 

 fruits and are the chief agents of seed dispei-sal. 

 Birds also (li.stribute the seeds. This weed tree 

 commonly covers quickly all openings resulting 

 from cutting of trees in the forest. Its open shade 

 provides a good environment for the development 

 of a new forest. 



PiTRLic FORESTS. — Cambalache, Carite, Guaja- 

 taca, Guilarte, Luquillo, Maricao, Rio Abajo, 

 Susi^ia, Toro Negro, Vega. 



Municipalities where especially common. — 1, 

 5, 10, 14, 17, 19, 22, 23, 25, 27, 31, 34, 35, 36, 40, 43, 

 45, 49, 50, 51, 52, 53, 58, 59, 60, 62, 64, 70, 73, 74. 



Range. — Throughout West Indies from Cuba 

 and .Tamaica to Trinidad and Tobago. Also fi-om 

 Yucatan, Mexico, to Costa Rica and recorded in 



66 



