LEGUME FAMILY (LEGUMINOSAE) 



CASSIA SUBFAMILY (CAESALPINIOIDEAE; CAESALPINIACEAE) 



74. Casia de Siam, Siamese cassia Cassia siamea Lam.* 



This introduced tree commonly planted along 

 highways and in windbreaks is characterized by : 

 (1) a generally erect crown, not spreading like 

 most similar species; (2) even pinnate leaves 9-13 

 inches long, with 1-2--2-2 paired oblong or lance- 

 shaped leaflets rounded at both ends and slightly 

 shiny green above; (3) the erect large terminal 

 clusters of numerous bright yellow flowers I14 

 inches across the 5 rounded petals; and (4) the 

 many long, narrow, flat, dark brown pods which 

 split open to release the seeds. 



A medium-sized evergreen tree to 60 feet in 

 height and 1 foot in trunk diameter or sometimes 

 larger, with straight axis. The bark is gray or 

 light brown, smoothish but becoming slightly fis- 

 sured. Inner bark is light bi'own, gritty and taste- 

 less. The twigs are greenish and minutely hairy 

 when young, turning brown. 



The alternate leaves bear leaflets in pairs along 

 the slender, grooved, green and reddish-tinged axis 

 on short stalks i/g "i^h long. The leaflet blades 

 are almost all the same size, I14-3 inches long and 

 ■V^~T^s i'T^li broad, with a tiny bristle tip, the edges 

 without teetli, tliin, the upper surface almost hair- 

 less, and the lower surface gray green with minute 

 hairs. 



Flower clusters (panicles) are branched, 8-12 

 inches long and 5 inches broad, with many, almost 

 regular flowers on straight, yellow-green, finely 

 hairy stalks l-li/i inches long. There are 5 con- 

 cave, pointed, greenish-yellow, finely hairy sepals 

 S'lR inch long; 5 spreading, nearly equal, yellow 

 petals %-% inch long, short-stalked; 7 stamens of 

 different lengths and 3 smaller sterile stamens ; and 

 a pistil with pale green, minutely hairy, 1-celled 

 ovary and curved style. 



The pods, so nmiierous that tliey sometimes give 

 an initidy appearance to the tree, are 6-10 inches 

 long, about 1/0 inch broad, and V^g inch thick, stiff, 

 and often slightly curved. They split up the sides 

 into 2 parts, releasing the many flat, shiny, dark 

 brown seeds ^/iq inch long and 16,000 to a j^ound. 

 In flower and fruit throughout tlie year. 



The sapwood is light brown and moderately 

 hard. The heartwood is dark brown and streaked 

 and hard. The wood, which is very susceptible to 



attack by dry-wood termites, is used locally as a 

 good fuel and for posts. Elsewhere employed for 

 construction, furniture, turnery, and similar pur- 

 poses. Tannin has been extracted from the bark. 



In Puerto Rico and the Virgin Islands the 

 principal uses of the trees a.re for ornament, shade, 

 aiul windbreaks. They form good windbreaks be- 

 cause they retain a deep closed crown. This 

 s])ecies is a relatively recent introduction in Puerto 

 Rico but now widespread as a result of distribu- 

 tion of quantities of seedlings by the government. 

 It was brought to Jamaica before 1837 and in 

 ( Guadeloupe has been planted as shade for coffee 

 and cacao. The trees are propagated by seeds, 

 grow very rapidly in full sunlight, and are suitable 

 for fuel within a few years. However, they are 

 very suscejjtible to attack by scale insects. 



The seeds, pods, and foliage are toxic to hogs 

 and cause death quickly after being eaten. As 

 hogs relish the poisonous leaves, farmers in 

 Puerto Rico have suffered losses. Trees blown 

 over or broken by storms increase the danger. 

 Thus, swine and ]5erhaps other livestock should 

 be kept away from these trees. 



Commonly planted along highways and streets 

 and in parks and yards in both the moist and dry 

 coastal regions, the moist limestone region, and in 

 the lower mountain regions of Puerto Rico. Also 

 common, especially in windbreaks, in St. Croix, 

 St. Thomas, and St. John. 



Raxge. — Native of East Indies, Malaya, India, 

 and Ceylon but spread by cultivation. First de- 

 scribed from Siam, as the common and scientific 

 names indicate. Widely planted through West 

 Indies in Greater Antilles and many of Lesser 

 Antilles to Trinidad and escaped and naturalized 

 locally. Less common in southern Florida and 

 from Guatemala to northern South America. 



Other commox names. — casia amarilla, casia, 

 casia siamea (Puerto Rico) ; yellow cassia (Virgin 

 Islands) ; flamboUan amarillo (Dominican Re- 

 public) ; casia siamea (Cuba) ; Siamese senna, 

 Siamese shower, kassod-tree (L'nited States); 

 Siamese cassia, kassod-tree, Bombay blackwood 

 (English) ; casse de Siam (Guadeloupe). 



Botanical s y n o n y m. — Sciacn.^sia siamea 

 (Lam.) Britton. 



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