Three-tip sage (Artemisia tripartite) with visible yellow flowers. – Photo Courtesy and Copyright Dr. Leila Shultz
Zane Gray’s “Riders of the Purple Sage” and Steve Tremble’s “Sage Brush Ocean” are book titles that may invoke excitement from your literary past. Or you may be traveling along the interstates and side roads of our great state as monotony sets in and drowsiness tightens your grip on the wheel while you nod your way through endless miles of this seemingly drab landscape.
In science jargon it’s referred to as sage steppe, the dominant landscape throughout much of Utah and the Great Basin. Much of this maligned biotic community has been degraded or lost through various mismanagement practices. Sage Steppe is considered an endangered ecosystem despite the seemingly large area it inhabits, primarily due to fragmentation. And the iconic Gunnison sage grouse has followed its demise having recently been placed on the threatened species list.
I just returned from spending a day of study in the field with 16 college students running transects for the Grand Teton N.P. The park is spending millions in sage steppe restoration work to reclaim this critical plant community.
Sagebrush is an important member of an ecosystem that helps support many birds, reptiles, amphibians, and mammals, as well as an abundance of insects and microbes. One study found nearly 300 arthropod species directly living on just a few plants including- 72 spider, 237 insect, 42 of which were gall-forming, amongst many other species. Such diversity also indicates that sage is playing an important part in maintaining the health of the environment providing ecosystem services such as soil protection, water conservation and nutrient cycling.
Sage is well adapted to the demands of semi-arid deserts. It has tap roots that can go over 15 feet deep to suck up any ground water that might exist and forms extensive webs of surface roots in association with symbiotic fungal hyphae to efficiently gather any rain that might fall. Oftentimes, sagebrush grows in clonal communities with members that can live over 100 years!
Aromatic odors emanating from sage, especially following a downpour of rain, comes from a mix of chemicals including camphor, terpenoids, and a cocktail of other volatile compounds. Some of the chemicals have anti-herbivory action by killing the gut bacteria of carious browsers although pronghorn antelope seem to have evolved resistance to these toxins. Other browsers like cattle, sheep, and mule deer can only eat sagebrush in small doses or whan the leaves are young and tender.
It is this mixture of molecules that sagebrush produces which come into play for communication. Sagebrush is eaten by many mammals and insects. When sagebrush is browsed on by a pronghorn or grasshopper volatile compounds are released from the wound that warn other branches of the same sagebrush as well as the neighboring sage about the potential threat. The sagebrush in the area react to the warning by metabolizing toxins that make them taste unappealing and that cause digestive discomfort for future herbivores who try to make a meal of them.
Native Americans considered sage a sacred plant. It offered medicine, clothing, shelter, and was commonly used in their ceremonial sweat lodges. Last but not least, my lovely granddaughter was given the name Sage. So the next time you find yourself surrounded by our “sagebrush ocean” pay tribute to this vibrant and intricate community of life.
Jack Greene, a lover of sagebrush.
Credits:
Pictures: Courtesy and Copyright Dr. Leila Shultz
Text: Jack Greene, Bridgerland Audubon Society
Additional Reading:
Cutthroat Trout on the Logan River, Copyright (c) Chadd VanZanten, Photographer