126. RHAMNUS PURSHIANA BEARBERRY. 23 



126. RHAMNUS PURSHIANA, DO. 



BEARBERRY, SACRED-BARK BUCKTHORN, SHITTIM-WOOD, WILD CHERRY. 



Ger., Kreuzdorn von Pursh; Fr., Nerprun de Pursh ; Sp., Cascara 



Sagrada. 



SPECIFIC CHARACTERS -.Leaves deciduous, elliptical to obovate, prominently 

 veined, 2-7 in. long, mostly acute at apex and obtuse rounded or subcordate at base, 

 serrulate to nearly entire with wavy margins, with scattering hairs beneath and 

 along the veins above; petioles scarcely in. in length, and as with the new growths 

 clothed in a brownish pubescence; stipules early deciduous. Flowers mostly perfect, 

 5-nunierous, with peduncles longer than the petioles, in umbellate cymes; calyx with 

 acuminate lobes ; petals minute and bifid at apex, hood-shaped and enveloping the 

 short stamens. Fruit black at maturity, globose-obovid, scarcely in. long, more or 

 less 2-3-lobed, with thin flesh and containing 2-3 obovate nutlets rounded on the back. 



(The specific name, Purshiana, is in compliment to Frederick Pursh, who first dis- 

 covered the species.) 



A small tree occasionally attaining the height of 40 ft. (12 m.) and 18 

 in. (0.45 m.) diameter of trunk, with large branches and full rounded 

 top. The bark of trunk is of a bluish-gray color mottled with whitish, 

 quite smooth and slightly checked longitudinally. It considerably 

 resembles the bark of the beech in the east. 



HABITAT. From the vicinity of Puget Sound southward to Lower 

 California and eastward into Montana, Colorado and Texas, on slopes 

 and uplands, often in the shade of other trees, and attaining its best 

 development in northern California and western Oregon. In many 

 localities it is no more than a large shrub. 



PHYSICAL PROPERTIES. Wood rather light, hard, close-grained, com- 

 pact, satiny, susceptible of a smooth polish, and with numerous fine 

 medullary rays. It is of a light yellowish-brown color, streaked with 

 purplish-brown, and with light yellow sap-wood. Specific Gravity, 

 0.5672; Percentage of Ash, 0.67; Relative Approximate Fuel Value, 

 0.5634; Coefficient of Elasticity, 91268; Modulus of Rupture, 750; Re- 

 sistance to Longitudinal Pressure, 621; Resistance to Indentation, 192; 

 Weight of a Cubic Foot in Pounds, 35.35. 



USES. Little, if any, use is made of the wood of this tree, but its 

 bark is a very important product on account of its medicinal properties. 



MEDICINAL PROPERTIES. The bark of this tree is considered an 

 excellent cathartic medicine, and is extensively administered in the 

 form of extracts and tinctures. 



ORDER SAFINDACEJE: SOAPBERRY FAMILY. 



Leaves simple or compound. Flowers polypetalous, often irregular and mostly 

 symmetrical; sepals and petals each 4-5, imbricated in the bud, the petals inserted 

 with the 5-10 stamens on a perigynous or hypogynous disk; ovary 2-3-celled and 

 lobed, usually 1-2 ovules in each cell, embryo mostly convoluted; no albumen. 

 Fruit a membranous, inflated pod, a leathery thick subspherical pod with nut-like 

 seeds, or a winged samara. 



