Frangula purshiana
species of plant
Frangula purshiana (cascara, cascara buckthorn, cascara sagrada, bearberry, and in Chinook Jargon, chittem stick and chitticum stick; syn. Rhamnus purshiana) is a species of plant in the family Rhamnaceae. It is native to western North America from southern British Columbia south to central California, and eastward to northwestern Montana.
The dried bark of cascara was used as a laxative in folk medicine by the indigenous peoples of the Pacific Northwest, and later worldwide in conventional medicines until 2002.
Description
Cascara is a large shrub or small tree 4.5–12 m (15–39 ft) tall, with a trunk 20–50 cm (7.9–19.7 in) in diameter. The buds have no scales, unique for the northwest region.
The thin bark is brownish to silver-gray with light splotching (often, in part, from lichens); the inner bark is smooth and yellowish (turning dark brown with age and/or exposure to sunlight). Cascara bark has an intensely bitter flavor that will remain in the mouth for hours, overpowering and even numbing the taste buds.
The leaves are simple, deciduous, alternate, clustered near the ends of twigs. They are oval, 5–15 cm (2.0–5.9 in) long and 2–5 cm (0.79–1.97 in) wide with a 0.6–2 cm (0.24–0.79 in) petiole, shiny and green on top, and a dull, paler green below; they have tiny teeth on the margins, and 10–12 pairs of pinnate veins.
Begin with the source’s own compact description: “Frangula purshiana” is species of plant. The dossier treats that line as a proposition to test through Frangula, purshiana and species, not as a finished interpretation.
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This entry incorporates text from “Frangula purshiana” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.