CASHEW FAMILY (ANACARDLACEAE) 



Key to the 6 species illustrated (Nos. 130-135) 

 A. Leaves simple. 



B. Leaves elliptic or obovate. roiinded at both ends or slightly notched at apex — 130. Anacardiiim occidentale. 

 BB. Leaves lance-shai)ed, long-pointed at both end.s — 131. Mangifcra indica* 



AA. Leaves pinnate. 



C. Leaflets usually 5 (3-7), ovate, blunt-pointed or minutely notched at apex; sap poisonous to the touch — 132. 



Metopium toxiferum. 

 CC. Leaflets 9-25. 



1). Leaflets mostly lance-shaped, long- or short-pointed at apex, with .short stalks about % inch long. 

 E. Leaflets inconspicuously toothed — 133. Spotidias diilcis* 

 BE. Leaflets not toothed — 134. Spondias nwmbiii. 

 DD. Leaflets elliptic, rounded or short-pointed at apex, almost stalkless — 135. Spondias purpurea* 



130. Pajuil, cashew 



Known for its cashew nuts and fruits, this small 

 tree of sandy areas on the north coast of Puerto 

 Rico, sometimes planted, is identified by: (1) a 

 dense irregular crown of obovate or elliptic, dull 

 blue-green, leathery leaves 2i/o-6 inches long and 

 13/4-3 inches broad, rounded at both ends or slight- 

 ly notched at apex, with the edges turned under 

 and with prominent sunken lateral veins nearly 

 at right angles to the midrib; (2) many fragrant 

 pinkish flowers about % incli long, with 5 very 

 narrow petals, short-stalked and crowded toward 

 ends of terminal branched clusters; and (3) the 

 very odd fruits consisting of a shiny gray-brown 

 kidney-shaped or bean-shaped nut (edible only 

 when roasted), about 1-11/4 inches long on a yel- 

 low or reddish, fruitlike, enlarged, pear-shaped 

 stalk or false fruit about 13/4-3 inches long and 

 13/4-2 inches broad, juicy and edible, thus appear- 

 ing as if the nut grows outside the fruit. The nut 

 shell contains a caustic poisonous oil which blisters 

 or burns the skin. 



An evergi-een tree to 20 feet high and 6 inches 

 in trunk diameter, or often shrubby. The light 

 gray to brown bark is smoothish, becoming slightly 

 fissured. The whitish to reddish-brown inner bark 

 is thick, bitter, and a.stringent, and contains a 

 milky juice, and larger trunks yield a gum. Twigs 

 are yellow green and finely liairy when young, 

 becoming light gray, stiff, and crooked. 



The alternate leaves have broad yellow-green 

 petioles 1,4-^2 i'l^h long. Leaf blades slightly 

 thickened, pale beneath. 



The widely spreading flower clusters (panicles) 

 are 4—19 inches long and nearly as broad. Flowers 

 are male and bisexual on the same tree (polyg- 

 amous). Calyx is more than %f^ inch long, light 

 green and finely hairy, narrowly 5-lobed nearly 

 to ba.se; the 5 pinkish petals yellow green at first 

 are %-V2 i'^ch long, long-pointed, spreading and 

 curved backward, and miiuitely hairy ; 10 or fewer 

 stamens, 1 much longer than the others, slightly 

 united at base; and in bi.sexual flowers a pistil on 

 a disk with 1-celled ovary and slender curved 

 style on 1 side. 



The nuts, which are the true fruits, are attached 

 at end, dry, and do not split open. Inside the 

 poisonous shell is 1 large curved seed nearly 1 inch 

 long, the edible cashew nut. As the nut matures, 



286 



Anacardium occidentale L. 



the stalk (receptacle) at base enlarges rapidly 

 within a few days into a fleshy fruitlike structure 

 broadest at apex, popularly known as the fruit. 

 This thin-skinned edible cashew "fruit"" has light 

 yellow spongy flesh, which is very juicy and pleas- 

 antly acid and slightly astringent when eaten raw 

 l)ut highly astringent when green. Flowering 

 from February to May, the fruit maturing from 

 Ajn-il to August. 



The wood is whitish, brownish, or pinkish, of 

 medium hardness, mediumweight (specific gravity 

 0.5), moderately strong, and easy to work but 

 susceptible to attack by dry-wood termites. 

 Though little used in Puerto Rico, the wood has 

 been employed elsewhere locally in construction 

 and carpentry, including boatbuilding, yokes, 

 hubs, etc., and for charcoal. The bark has served 

 in tanning. Mucilage repellent to insects and var- 

 nish liave been made from the gum, which is 

 similar to gum arabic, and an indelible ink from 

 the milky sap. 



The tree is valued primarilv for the inits and 

 fruits. Roasted cashew nuts are an item of world 

 commerce. In roasting, the poisonous oil of the 

 shell is removed by heat, but the caustic fumes 

 and drops of oil may blister the skin and inflame 

 the eyes if care is not exercised. The "fruits" are 

 eaten fresh or in preserves and have been em- 

 ployed in preparation of wine and vinegar. 



Cardol oil, the poisonous, thick, black, very acrid 

 oil of the shell of the nut, has been used medici- 

 nally and to preserve book bindings, carved wood, 

 and similar articles against insects. A nutritious 

 oil similar to olive oil has been obtained from the 

 seeds. The bark has been the source of medicines 

 also. As the flowers are attractive to bees, this 

 species has been classed also among the honey 

 plants. 



Living fences have been made from the trees, 

 which sometimes are grown for ornament. The 

 l^lants mature at a very early age and are short- 

 lived, flowering and fruiting as early as the second 

 or third or sometimes the first year after sowing. 

 Through the tropics the trees are grown in planta- 

 tions for the nuts and "fruits," but they are semi- 

 wild or naturalized in many regions. In the Vir- 

 gin Islands the trees are uncommon but widely 

 planted for shade and fruit, such as around houses, 



