Growing as a small deciduous tree in the big-timber regions of the Pacific Northwest, the cascara buckthorn (Rhamnus purshiana) contains a medicinal extract in its bark that's a sure cure for one of mankind's most common maladies. For over 100 years, cascara buckthorn has brought relief to those suffering from constipation.
Although at 10' to 40' tall it's dwarfed by Douglas fir and other commercial species, the cascara buckthorn draws a small army of "cascara barkers" deep into the shady woods every summer. Using nothing more than a sharp knife, itinerant workers from Northern California to British Columbia collect about one million pounds of bark. A typical barker harvests 250 pounds in a day and collects $50 for the effort. When in doubt about the species, barkers simply taste a small sample of the bark for the bitter flavor and mouth-numbing effect that marks it as cascara.
Local Indians first alerted the area's Spanish missionaries to the beneficial effects of this bitter bark, which was thereafter dubbed cascara sagrada or "holy bark." Yet, it wasn't until 1878 that the Parke-Davis company began selling cascara extract to the rest of the country in an over-the-counter formula. By World War II, GIs weary and bloated with C-rations called cascara-based medicine "CC pills."
Cascara wood varies from yellow to orange-brown in color. Although easy to machine and finish, it has little commercial value.
Today, newer formulas have eroded cascara's once-dominant medicinal position. But if you read the labels in the pharmacy, you'll still occasionally see the holy bark—one of nature's safest, most effective laxatives—as an ingredient.