PHARMACAL PLANTS AND THEIR CULTURE. 
141 
exact comparative medicinal value. The Indians have long made medic- 
inal use of these plants and the whites ascertained their therapeutic 
value from the Indians. (See Dispensatories and Materia Medicas.) 
721. Rhamnus californica Eschw. Cascara sagrada (sacred bark). 
Coffee berry. Rhamnacece. 
Very common in California, varying in size from a small shrub to a 
tree of fair proportions. Readily cultivated. Common along the coast 
region. 
722. Rhamnus californica tomentella Br. and Wats. California 
coffee tree. Sacred bark. Rhamnacece. 
This tree is found in the interior of California, and is closely similar 
to the species both as to appearance and as to properties. A decoction 
is used as a poison oak remedy. The seeds are said to be used as a 
substitute for coffee. 
723. Rhamnus crocea ilicifolia Greene. Rhamnacece. 
The Piute Indians have used this plant as a cathartic and diuretic. 
The berries are eaten as food, and it is said that they tinge the veins 
red, due to a deposit of coloring matter. 
724. Rhamnus ilicifolia K. Buckthorn. Rhamnacece. 
Used medicinally by Indians. Has an orange-colored inner bark. 
Requires more careful study. (Contrib. U. S. Nat. Herb. 7 : 369.) 
725. Rhamnus purshiana D. C. Cascara sagrada. Rhamnacece. 
This species is exceedingly abundant in Oregon and Washington, 
somewhat less abundant in northern California. This is supposed to 
be the true medicinal sacred bark. 
726. Rheum species and varieties. Rhubarbs. Polygonacece. 
The rhubarbs, culinary as ivell as medicinal, thrive well in the State, 
particularly in the Coast region. The plants are propagated from 
seeds and from the lateral shoots, which are set out about six to eight 
feet apart, and left to grow from four to seven years, when the roots are 
dug up during dry weather, peeled and cut into pieces, varying in size. 
The initial drying is done in the open and completed by artificial heat, 
not to exceed 80° P. (See Chap. III.) (Proc. A. Ph. A. 25:132, 
1877), (Proc. A. Ph. A. 26:196-201, 1878), (Proc. A. Ph. A. 23:145. 
1875.) 
727. Rhododendron californicum Hook. California rose bay. Eri- 
caceae. 
It is stated that the honey made from the flowers of this plant is 
poisonous. The same is reported of the honey from R. occidentale 
Gray. The leaves and roots of the latter plant are said to contain a 
powerful narcotic poison. 
