Extract Ratio:5:1,10:1
Cascara sagrada (Rhamnus Purshiana, U.S.P.) is the dried bark of Rhamnus purshianus, DC. (N.O. Rhamneae), a shrub growing in North California, Oregon, and Washington. It is collected in the spring and early summer, and dried in the shade. It is generally considered that the action of the bark becomes milder and less emetic by keeping; hence matured bark (three years old) is preferred for pharmaceutical purposes. The bark occurs in quilled, channelled, or curved pieces, varying considerably in size, but often about 10 centimetres long, 1 to 2 centimetres wide, and 1 to 2 millimetres thick, thin bark being preferred for use in pharmacy. The cork is nearly smooth, dark purplish-brown in colour, and bears scattered lenticels, but in most pieces the cork is more or less completely covered by a whitish coat of lichens; the inner surface is of a yellowish-brown or dark brown colour, and faintly striated and corrugated. It breaks with a short fracture, which is somewhat fibrous near the inner surface. The transverse section exhibits a narrow purplish cork, a yellowish-grey cortex, in which groups of sclerenchymatous cells may be distinguished, and a brownish-yellow bast, containing wavy, medullary rays. The odour is characteristic, though not powerful; the taste is nauseous and persistently bitter.
