PNW Native
Cascara buckthorn can range from a small shrub to a 35-ft tall tree. Leaves are 2-6 inches long, alternate, glossy, oblong, deep green, and have strikingly indented parallel venation. (Mackinnon & Pojar, 1994) Flowers are small, green-yellow, and inconspicuously arranged in a single-stalked cluster in the center of a leaf axil, with male and female flowers on different clusters blooming from April to June. (Mathews, 2021) Fruits range from a yellow to purplish-black single-seeded berry, which reach a size of up to ½ inch. (Mackinnon & Pojar, 1994) Cascara shrubs are found in low to montane elevations on both sides of the Cascades from Washington to south-central Oregon, (Lloyd & Chambers, 2014).
Cascara shrubs grow in riparian environments and forests in low to montane elevations, but they prefer shady, coniferous, streamside environments. (Lloyd & Chambers, 2014) The shrub is widely found in the mountainous forests of the region, but it is not particularly abundant. Cascara buckthorn is common winter browse for mule deer and elk, with Oregon gray foxes, raccoons, ring-tailed cats, and Olympic black bears also reported to use it as a source of sustenance. A few species of birds, including the Oregon ruffled grouse and band-tailed pigeon consume the berries. It is not a source of forage for livestock. (Haebeck, 1996)
Cascara bark was left to dry-cure for months, then boiled to make tea or syrup by the Nuxalk, Salish, Quileute, Nuu-cah-nulth, and Kwakwaka’wakw tribes among others. Bark was harvested in strips in spring or summer, aged for a year, then consumed the next summer. (Mackinnon & Pojar, 1994) The Kootenai and Flathead tribes of Montana that also consumed the laxative tea believed that the direction the strips of bark were harvested in would change the properties of the tea: if the strips were pulled from down to up the resulting medicine would be emetic and if stripped from up to down the drug would be purgative. (Habeck, 1992) Cascara had other medical uses including washing sores, treating excess bile, and easing heart strains.
When bark from the tree would be harvested, indigenous harvesters would ‘talk to the tree’ and ask consent to harvest from it, which was a common cultural practice for harvesting and using land resources, plant or animal. Additionally, a study conducted in 1990 showed that “more than fifty-one of the eighty-three reported medicinal remedies used by Saanich or Cowichan healers in one study (Turner and Hebda 1990) were used similarly in at least one other Northwest Coast group.” (Turner, 2015, Vol 2 p. 132) This highlights the complexity of knowledge-sharing amongst coastal peoples of the region as well as complex trade networks facilitating the spread of knowledge and goods.
After learning of cascara’s potent laxative properties from native Northwesterners, settlers manufactured the bark of the shrubs into a potent laxative. In the 1890s, the laxative, sold under “Chittambark” or “Cascara Sagrada”, holy bark in English. (Mathews, 2021)
When the bark is stripped from a cascara tree, the plant will die. Mature cascara trees are rare, and cascara is not an abundant shrub in its ecosystems. This dearth of cascara is due to overharvesting in the 19th century for pharmaceutical purposes. (Turner, 2015) United Plant Savers have placed cascara on their “To Watch” list due to its precarious status. Mindful practices must always be considered with harvesting and foraging. (Mathews, 2021)
MacKinnon, A., & Pojar, J. (1994). Plants of the Pacific Northwest Coast: Washington, Oregon, British Columbia & Alaska. Lone Pine Publishing : Partners Publishing : B.C. Ministry of Forests.
Mathews, D. (2021). Cascadia revealed: A guide to the plants, Animals & Geology of the Pacific Northwest Mountains. Timber Press, Inc.
Turner, N. J. (2015). Ancient pathways, ancestral knowledge: Ethnobotany and ecological wisdom of indigenous peoples of Northwestern North America. McGill-Queen’s University Press.
