Over the centuries, various wild plants have been tried as teas, most of them lacking significant caffeine content, and in many cases, having the potential to sicken the imbibers. But the explorers, settlers and native peoples who did the experimenting had to settle for whatever species they could find in the remote boreal forests and deserts that they occupied or crossed.
Labrador tea or bog tea was a tea substitute made from any of three species of low-growing bog and boreal forest shrubs formerly considered to be in the small genus Ledum. These species, Rhododendron tomentosum, R. groenlandicum, and R. neoglandulosum are now absorbed into a separate section of the large genus Rhododendron within the family Ericaceae. Despite their frequent mention in the historical literature, opinions apparently differ as to the teas’ quality. One 19th century explorer, damning with faint praise, described one of the Labrador teas as “…a capital beverage in absence of a better.” (Fernald et al 1958).
Despite their use for human consumption, all the former members of the Ledum genus (as well as other rhododendrons) contain ledol (C15H26O)- a poisonous sesquiterpene (a toxic terpene of essential oils) which can cause cramps, paralysis and delirium but ordinarily is not lethal. Presumably preparation of the tea may aid in reducing the poisonous properties. The large class of hydrocarbon compounds called terpenes are generated in abundance by leaves and stems (e.g., in sap) of coniferous trees like pines and spruce, but many other plants like rhododendrons, cannabis, oak trees and even common vegetables produce terpenes as well. Terpenes and their derivatives are volatile and released by plants into the atmosphere where they participate in the formation of clouds and haze. Today, Ledum-derived preparations are sold as boosters of immunity, healing, and numerous other benefits that presumably contribute to well-being. A fourth species, R. lapponicum, a matted, low shrub of the far North, has also been prepared as a tea, but reports suggest the plant might be better used, as it was once in Lapland- as a mouse repellent!
Bog-rosemary (a single species known either as Andromeda glaucophylla or A. polifolia var.glaucophylla, depending on source) was reported as used by Ojibwe Indians as a tea. This is another northern bog-inhabiting member of the Ericaceae. As the leaves of bog-rosemary contain the toxic andromedotoxin (or rhodotoxin), a diterpene characteristic of the Ericaceae, the tea is made or consumed only by drawing water through the leaves without steeping or boiling, thereby preventing or reducing the migration of the toxin into the tea itself.
Andromedotoxin is known to contaminate the honey that is made by bees from the pollen and nectar of Rhododendron and related ericads. Chemically similar to components of turpentine, the andromedotoxin resin burns the mouth and appears to inhibit would-be herbivores. Although usually not reaching toxic levels, the honey of two species of Rhododendron growing around the Black Sea is known to have rendered those who gorge on it to become temporarily stupefied to the point of immobility. The tainted honey is recorded as having been used to stupefy enemy soldiers to the point of defenselessness on several occasions throughout history. The soldiers of Pompey, the famed general of ancient Rome, were so victimized by Mythridates of Pontus, as were the Russian foes of Olga of Kiev in 946 (CE).
Leather-leaf (Chamaedaphne calyculata)- like the previous species, is yet another low woody ericad from northern latitudes that has been reported in the literature as having been tried as a tea. The same cautions with respect to the toxin andromedotoxin that apply to bog-rosemary would also apply to leather-leaf.
Wintergreen or checkerberry (Gaultheria procumbens of the Ericaceae) is a small, trailing (rather than an upright, woody shrub as are the previous species) perennial of northern deciduous and coniferous woods, highly esteemed as a tea substitute. This species has a distribution that extends as far south as Virginia and Georgia (in the mountains).
As early as the 18th century in Quebec, the court-physician, a Dr. Gaultier, was an enthusiastic advocate of winterberry tea (Fernald et al., 1958). His enthusiasm has been memorialized in the generic epithet. Winterberry was also widely used as tea by woodsman in the northern U.S. and Canada and as a source of wintergreen oil. Its bright red berries have long been considered as one of the tastiest of wild fruits. The second member of the genus, G. hispidula, is smaller-leaved, and found farther north but also provided a tea. Its fruits are white and eaten fresh or in preparations that ranked it as “one of the greatest delicacies of the northern woods (e.g., the Gaspe’ and Newfoundland)” (Fernald et al. 1958).
Turning from bogs and boreal forest, we visit the deserts of the southwestern U.S. and adjacent Mexico. Here several species of Ephedra are widespread. Ephedra is a genus of low shrubs of desert regions that produces cones rather than flowers and is therefore considered as a gymnosperm, rather than an angiosperm, the class of flowering plants. As such, Ephedra is more closely related to coniferous trees (e.g., pines and spruce), yews and cycads than to flowering plants. Ephedra plants give little impression of having the potential to be of culinary interest to humans. Stems are green, tough, and tannin-laden, and are the chief organ of photosynthesis. Yet the ephedras of American and Mexican deserts were widely used as teas and given the common names of Mormon Tea, Mexican Tea, squaw tea or Indian tea. The tea is made by boiling the green or dried stems; while leaves are present, they are reduced to small scales and therefore contribute little to the tea or to the plant’s energy budget.
Ephedra species have in common the presence of the alkaloid ephedrine (C 10H15 NO) which is chemically related to methamphetamine as well as to the neural transmitter epinephrine. E. nevadensis and to a lesser extent, several other species of Ephedra growing in New World deserts, were used by various peoples inhabiting or settling in arid North America (including Mexico) to make a tea. Today there is little or no use of New World ephedra for making tea, but ephedrine remains available as a decongestant and bronchodilator for temporary relief from breathing and related problems. A number of potential side effects and cautions accompany the use of ephedrine for these and other purposes.
The Chinese ephedra, E. sinica, has served as a source of traditional Chinese medicines for millennia and is widely marketed in North America. However the U. S. Food and Drug Administration has recently banned the sale of dietary supplements containing ephedrine after cases of serious side effects and death were connected to consuming products containing ephedrine. Its use for applications other than dietary ones remain legal and broadly advertised.
Mesquite tea- (Prosopis velutina, one of about eight Prosopis species). This woody shrub or small tree (reaching about 20’ or 6 m, or even higher in Mexico) of the bean family (Fabaceae) is one of the most characteristic plants of arid and semi-arid regions of the Americas. Its use in grilling meats is widely appreciated in the U.S. but among its many uses, the flowers can be boiled to produce a tea. Pods and seeds can be ground into a meal that is used to make bread or allowed to ferment to produce a fizzy alcoholic drink. Leaves also serve as source of tea although this tea is best known for its use in curing headaches, gastric issues and painful gums!
On the other hand, in many places mesquite is regarded as a problem species and is classified as an invasive weed. In Australia four species of mesquite and several hybrids were introduced by man and are aggressively occupying grasslands, rangelands, and streamsides. One or more of the species of Prosopis also are invasive in South Africa, India, the West Indies and elsewhere. Even in the U.S., where several mesquite species are native, mesquite has invaded areas outside its native habitat, causing problems. Mesquite presumably co-evolved with large herbivores like mammoths and ground sloths which ate the pods and left the seeds to germinate. Today cattle fulfill this role, making it more difficult to control mesquite in rangelands.
Fernald, M.L., A.C. Kinsey and R.C. Rollins 1958. Edible Wild Plants of Eastern North America. Harper & Bros. New York.
Mayor, Adrienne. Mad Honey! Bees and the Baneful Rhododendron. Archaeology 46:32-40.