RUE FAMILY (RUTACEAE) 



102. Espino rubial, white-prickle, Martinique prickly-ash 



Zanthoxylum martinicense (Lam.) DC. 



This medium-sized tree is characterized by: 

 (1) tlie very stout conical spines V^-l incli lon<j 

 and broad on the smoothish liglit gmy trunk and 

 usually smaller spines on the twigs; (2) the pin- 

 nate leaves with 7-19 stalkless oblong to lance- 

 shaped leaflets H/2-5 inches long and V2-'^V2 inches 

 broad, very finely wavy margined, and with mi- 

 nute glancl dots; (3) many small greenish-white 

 5-parted flowers %(i inch long and broad; and 

 (4) the dry fruits, deeply 5-parted, i/^ inch long 

 and s/ju inch broad, dark brown. 



An evergreen tree becoming 20-65 feet in 

 height and 18 inches in trunk diameter, with thin 

 spreading crown. The bark is smoothish, light 

 gray, about i/i inch thick, with spines on larger 

 trees becoming 2 inches long and broad. Inner 

 bark brown, with citrus spicy taste and also 

 slightly gritty. The twigs are gray, stout, brittle, 

 minutely bristly hairy when young, usually spiny 

 with many stout gray spines Vie-^ inch long. 



The alternate leaves are 6-12 inches long, the 

 axes and midribs finely haii-y and often spiny. 

 The leaflets are short-pointed to i-ounded at apex, 

 slightly oblique at base, thin, upper surface gi-een 

 and hairless, lower surface paler and minutely 

 hairy on veins. 



Flower clusters (panicles) are terminal and lat- 

 eral, much branched, 2-6 inches long and broad, 

 beai-ing many almost stalkless flowei-s, male and 

 female on different trees (dioecious). There are 5 

 minute sepals; 5 spreading petals; in male flowers 

 5 stamens longer than petals; and in female flowers 

 a pistil with deeply 5-lobed 5-celled ovary and 

 5-lobed stigma. The fruits are deeply 5-parted, 

 each part (follicle) sjditting open and with 1 

 nearly round shiny black seed Vs inch long. Flow- 

 ering and fruiting from spring to fall. 



The sapwood is whitish, and the heartwood light 

 yellow to light yellowish browni. The wood is of 

 medium weight (specific gravity 0.46), hard, of 

 medium to fine texture, with growth rings clearly 



defined, but without distinctive figure. It is very 

 susceptible to attack by dry-wood termites and 

 other insects and is not durable where exposed. 

 The rate of air-seasoning is rapid, but the amount 

 of degrade is considerable. Machining character- 

 istics are as follows : planing, shaping, boring, and 

 mortising are fair; turning and sancling are poor; 

 and resistance to screw sjilitting is good. 



Because of the small size of the remaining trees, 

 the wood is seldom used. It is suitable for boxes, 

 crates, general carpentry, low-grade furniture, 

 light construction, concrete forms, and similar 

 uses. 



This species requires overhead light and grows 

 i-apidly. In Trinidad it spreads naturally and 

 vigorously in clearings. It has been grown for 

 shade in Cuba and southern Florida, though the 

 spines may be objectionable for this purpose. 

 Also a honey plant. 



Widely distributed in the coastal, limestone, and 

 lower mountain forest regions of Puei'to Rico. 

 Also in Vieques, St. Croix, St. Thomas, St. John, 

 and Tortola. 



Public forests. — Cambalache, Carite, Guaja- 

 taca, Guanica, Guilarte, Luquillo, Maricao, Rio 

 Abajo, Susiia, Toro Negro, Vega. 



Municipalities where especially common. — 

 14, 20, ;30, 40, 42, 47, 68, 69. 



Range. — Throughout West Indies from Cuba 

 and Jamaica to Trinidad and Tobago. 



Other common names. — cenizo, espino, espin- 

 osa, ayua (Puerto Rico); pino macho (Domini- 

 can Republic) ; ayiia, ayua amarilla, bayua 

 (Cuba) ; jjrickly-yellow, yellow Hercules (Jamai- 

 ca) ; Martinique prickly-ash (English) ; Pepine 

 gomniier (St. Lucia); Tepine (Dominica); 

 le))inet (Trinidad) ; yellow-prickle (Tobago) ; 

 bois pine (Haiti) ; lepine jaune, lepuni jaune, 

 lepineux jaune (Guadeloupe, Martinique) ; yel- 

 low-prickle (Dutch West Indies). 



Botanical synonym. — Fagara martinicensis 

 Lam. 



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