by Terry Ryan
Break off a sprig of big sagebrush and inhale its aroma: the fragrance is clean, sharp and as cool as the smell of winter. Call it camphor blended with a touch of Christmas. Crush a few leaves between your fingertips and the scent is suddenly somewhat bitter and more pungent. Let the sprig dry for a few hours and you’ll find that the fragrance gradually loses its bite, softening to crisp evergreen with a hint of juicy berry.
Big sagebrush flourishes throughout North America’s Great Basin and sagebrush steppe. One of more than a dozen species of Artemisia, big, or tall, sagebrush is the most common, ranging from as far south as New Mexico all the way up into the Dakotas, Montana, and British Columbia. This woody-stemmed evergreen shrub is able to thrive in such widely diverse environments because it has double systems of roots, branches, and leaves.
First, let’s talk about the roots. One network of small roots laces out beneath shallow layers of soil, enabling the plant to soak up sudden rainfall or meltwater before evaporation occurs. Meanwhile tresses of longer, tougher roots plumb deeper into the earth, searching out underground water reserves.
Now let’s examine the branches. Big sagebrush produces both vegetative and reproductive branches. Vegetative branches are leafy. Small yellow flowers blossom on reproductive branches in late summer and early fall. After the seeds ripen, reproductive branches die off, but may remain on the shrub for another year.
Now for the leaves. The first type—non-lobed ephemerals—sprout in early spring and die off as the soil dries up in summer. Shorter leaves pop up in late spring and carry on photosynthesis throughout the winter. It’s from these shorter leaves, graced with three lobes at the tip, that big sagebrush derives its official name: Artemesia tridentata. Both the ephemeral and the lobed leaves are tiny, usually from one-quarter of an inch to one inch long. A coating of fine gray hairs covers each leaf, imparting a frostiness that gives big sagebrush its characteristic silvery green color. Run your hands along a branch of big sagebrush and you’ll find its leaves feel as soft and smooth as fine suede.
Big sagebrush is a survivor. A healthy shrub may live up to 100 years. It competes with native and non-native grasses, and tends to grow abundantly in areas damaged by overgrazing. The size of the shrub depends upon the moisture content of the soil. The average shrub stands from two to four feet tall; however, in dry areas big sagebrush may be as small as 6 inches, and in wetter climes the plant has been known to grow as high as 15 feet. Its branches provide winter forage for deer and elk, as well as a food and habitat for sage grouse and other birds and small animals.
Anthropologists have found that early Native Americans used big sagebrush for a variety of medicinal and domestic purposes. The Shoshone and Paiute used the leaves to relieve toothaches. The Coahuilla, Hopi and Tewa peoples brewed a potent tea to treat stomach ailments. The Navajo wrapped aching, rheumatic joints in bandages of wet sagebrush leaves; they also boiled a sagebrush tea for treatment of post-partum pain suffered by new mothers, as well as for coughs and colds. Other tribes burned or steamed the fragrant leaves to purify the air.
Whether or not you like the Christmasy, camphoraceous scent of big sagebrush is a matter of personal taste. But one thing is certain: mention sagebrush and you conjure up the myth of the American West. If the western states ever decide to fly their own flag, it will probably be the silvery green color of sagebrush.
Every week since 1991, Field Notes has inquired about Montana’s natural history. Field Notes are written by naturalists, students, and listeners about the puzzle-tree bark, eagle talons, woolly aphids, and giant puffballs of Western, Central and Southwestern Montana and aired weekly on Montana Public Radio.
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