MORMON TEA (EPHEDRA species) Main sources: Dimmit, Mark, "Ephedraceae (ephedra family)", in Steven Phillips and Patricia Comus, eds., 2000, A Natural History of the Sonoran Desert, pp. 236-38, Arizona-Sonora Desert Museum Press, p. 224; "Virtual Paleobotany", in http://ucmp.berkeley.edu/lb181/VPL/Dir.html. Ephedra, like the Horsetail (Equisetum) plant whose jointed stem structure its branches resemble, is a botanically important relic of a very distant geological past. In fact, there is current debate as to which evolutionary branch of the “Seed plants” (Spermatophytes) its family (the Gnetophytes) belongs -- whether the “Naked Seeds” (Gymnosperms, including prominently the conifers) or the “Boxed Seeds” (Angiosperms, i.e. the flowering plants). The Gnetophytes are joint-branched woody shrubs or vines (each branch segment appears to sit atop the other -- see below) whose Ephedra-like pollens are first known from the Triassic period (246-208 mya), leading some botanists to infer that Ephedra "represents the basal group in gnetotype evolution", which would mean that this xerophytic plant has survived more or less intact from that time. Like the other non-flowering seed plants, Gnetophytes were much more diverse during the Mesozoic era than they are today. Today only three genera remain -- one a moist-tropics type of vines, the second a bizarre, rare plant of the Namibian Desert in SW Africa, and the third are Ephedra species (distributed globally in arid lands, some 30 species, of which there are several in our area). In our area, Ephedra shrubs grow from 2 to 5 feet tall and wide, and their thin, green stems have leaves that are very greatly reduced and spike-like (look closely at the stems in the banner photo above, and also below). The jointed quality of the stems, which has led these types to be called "joint firs", may be examined more closely in this photo:
Here (below) is a large Ephedra located on the Pool Wash ridge road, beside a small Cholla cactus to the left (October 2002):
Their seeds are contained in papery cones which have flower-like qualities (reflecting their apparent marginality between Gymnosperms and Angiosperms), and their reproductive mechanisms also link them to the Angiosperms: below left, an ephedra in bloom (March 2003); right, a closeup of the cones/inflorescences showing their ambiguity: (click on right image to enlarge):
The stems contain ephedrine -- a bronchiodilator -- and pseudoephedrine -- a nasal decongestant. While currently available cold/allergy medications have been based on a Chinese species of Ephedra which contains much stronger concentrations of these drugs than our local plants (and which has been used by people in China for more than 4,000 years), stems from the Ephedra of our area were drunk in tea both by the O'odham and by Mormon settlers, hence the plant is known as “Mormon Tea” or "Squaw Tea.” Cattle will browse Ephedra, but only when other plants are unavailable, so when ranchers see it being browsed they know it's time to move the animals. (It was the main plant found in the dung of the last known surviving southwestern ground sloths -- see Pleistocene Megafauna.) Mormon Tea is, like Creosotebush, very drought-resistant, but under conditions of severe drought it will lose its green color and become an almost flaming orange, as in this specimen (below), photographed at the climax of the drought of May 2002:
(The green branches in the background are those of Palo Verde trees.) |
