'' Artemisia tridentata'', commonly called big sagebrush,MacKay, Pam (2013), ''Mojave Desert Wildflowers'', 2nd ed., , p. 264. Great Basin sagebrush or simply sagebrush (one of several related species of this name), is an aromatic

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

from the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

. It grows in arid and semi-arid conditions, throughout a range of cold

desert A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the la ...

steppe In physical geography, a steppe () is an ecoregion characterized by grassland plains without closed forests except near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the tropical and subtropica ...

, and

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher t ...

habitats in the Intermountain West of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

. Big sagebrush and other ''Artemisia'' shrubs are the dominant plant species across large portions of the Great Basin. Sagebrush provides food and

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

for a variety of species, such as sage grouse, pronghorn antelope, grey vireo, pygmy rabbit, and

mule deer The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer. Unlike the related whit ...

. Several major threats exist to sagebrush ecosystems, including human settlements, conversion to

agricultural Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created f ...

land, invasive plant species, and

wildfire A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a ...

s. Native Americans have used the plant medicinally. It is also useful as firewood.

Description

Big sagebrush is a coarse, many-branched, pale-grey shrub with yellow

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s and silvery-grey

foliage A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, f ...

, which is generally tall. A deep

taproot A taproot is a large, central, and dominant root from which other roots sprout laterally. Typically a taproot is somewhat straight and very thick, is tapering in shape, and grows directly downward. In some plants, such as the carrot, the taproot ...

in length, coupled with laterally spreading roots near the surface, allows sagebrush to gather water from both surface precipitation and the water table several meters beneath. Big sagebrush that is over a meter tall is an indicator of arable land, because it prefers deep, basic soils. Sagebrush is generally long-lived once it makes it past the seedling stage, and can reach ages of over 100 years. Artemisia tridentata 2

The species has a strong pungent fragrance (especially when wet) due to the presence of

camphor Camphor () is a waxy, colorless solid with a strong aroma. It is classified as a terpenoid and a cyclic ketone. It is found in the wood of the camphor laurel (''Cinnamomum camphora''), a large evergreen tree found in East Asia; and in the kapu ...

terpenoid The terpenoids, also known as isoprenoids, are a class of naturally occurring organic compound, organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeabl ...

s and other volatile oils. The taste is bitter and, together with the odor, serves to discourage browsing by many herbivores. It is an

evergreen In botany, an evergreen is a plant which has Leaf, foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season. Consisting of many diffe ...

shrub, keeping some of its leaves year-round (although it loses many of them in the late summer). The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

—attached to the branches at the axillary nodes—are wedge-shaped, long and 0.3–1 cm broad, with the wider outer tips divided into three lobes (hence the scientific name ''tridentata''). The leaves are covered with fine silvery hairs. The plant flowers in the late summer or early fall. The small yellow flowers are in long, loosely arranged tubular clusters. The fruits are seed-like and have a small amount of hairs on the surface. Big sagebrush can also reproduce through sprouts, which shoot up from the underground rhizome. The sprouts are an extension of the parental plant while seedlings are completely individualistic to any other plant. Among these two strategies, the seedlings need more moisture for germination and early survival. This is due to the sprouts being connected to already healthy and associated plants while the new seedlings will start anew.

Chemistry

Sagebrush essential oil contains approximately 40% ''l''-camphor; 20%

pinene Pinene is a collection of unsaturated bicyclic monoterpenes. Two geometric isomers of pinene are found in nature, α-pinene and β-pinene. Both are chiral. As the name suggests, pinenes are found in pines. Specifically, pinene is the major comp ...

; 7% cineole; 5% methacrolein; and 12% ''a''-terpinene, ''d''-camphor, and sesqiterpenoids.

Taxonomy

Much discussion and disagreement revolves around the question of how to divide the species into varieties and subgenera. The following

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

are accepted by some authors, though others advocate different systems. * ''A. tridentata'' subsp. ''tridentata'' ("basin big sagebrush") * ''A. tridentata'' subsp. ''vaseyana'' ("mountain big sagebrush") * ''A. tridentata'' subsp. ''wyomingensis'' ("Wyoming big sagebrush") – Found in the drier portions of the sagebrush steppe. Shrub density is generally less than 1 plant/m², with little herbaceous cover surrounding the shrub. * ''A. tridentata'' subsp. ''xericensis'' ("scabland big sagebrush") * ''A. tridentata'' subsp. ''spiciformis'' ("subalpine big sagebrush") * ''A. tridentata'' subsp. ''parishii'' ("Parish's big sagebrush")

Distribution and habitat

''Artemisia tridentata'' grows in arid and semi-arid conditions, throughout the Intermountain West of

. Sagebrush is not a

plant, but rather a resident of the

, in areas that receive of annual precipitation. Big sagebrush and other '' Artemisia'' species are the dominant plants across large portions of the Great Basin, covering some in 11 western U.S. states and Canadian provinces. The range extends northward through

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

's southern interior, south into

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

, and east into the western

Great Plains The Great Plains is a broad expanse of plain, flatland in North America. The region stretches east of the Rocky Mountains, much of it covered in prairie, steppe, and grassland. They are the western part of the Interior Plains, which include th ...

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

Nebraska Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Ka ...

, and the Dakotas.

Ecology

Sagebrush provides food and

for a variety of animal species, such as sage grouse, pronghorn, gray vireo, pygmy rabbit, and

. It is especially important to game animals during the winter. Sagebrush also creates habitat for many species of

grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...

es and

herb Herbs are a widely distributed and widespread group of plants, excluding vegetables, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal purposes, or for fragrances. Culinary use typically distingu ...

s. Besides providing shade and shelter from the wind, the long taproot of sagebrush draws water up from deep in the soil, some of which becomes available to these surrounding shallow-rooted plants. The terpenoid compounds in big sagebrush are thought to ward off herbivores. These oils, at high concentrations, are toxic to the

symbiotic Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biolo ...

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

in the

rumen The rumen, also known as a paunch, is the largest stomach compartment in ruminants. The rumen and the reticulum make up the reticulorumen in ruminant animals. The diverse microbial communities in the rumen allows it to serve as the primary si ...

of some

ruminant Ruminants are herbivorous grazing or browsing artiodactyls belonging to the suborder Ruminantia that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion, principally through microb ...

s like deer and cattle. Pronghorn are the only large

herbivore A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...

to browse sagebrush extensively. Damage to sagebrush plants caused by grazing herbivores results in the release of volatile chemicals, which are used to signal a warning to nearby plants, so that they can increase the production of repellent chemical compounds. This plant-to-plant communication can take place at distances of up to . Antilocapra americana

Several major threats exist to sage brush ecosystems, including human settlements, conversion to

land, invasive plant species,

s, and

climate change Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...

. Due to large periods of time where sagebrush was the primary shrub, many species have become adapted to this habitat. The burning of the shrubs leads to habitat loss of many species and can be very detrimental to the ecosystem as a whole. Furthermore, the destruction of native grasses and forbs by grazing and fire creates conditions where invasive plants colonize the area. The invasive species which has destroyed the largest amount of sagebrush habitat is cheatgrass (''Bromus tectorum''). Since its accidental introduction in the 1890s, cheatgrass has radically altered the native shrub ecosystem by replacing indigenous vegetation, and by creating a fire cycle that is too frequent to allow sagebrush to re-establish itself. Sagebrush lacks fire tolerance and relies on wind-blown seeds from outside the burned area for re-establishment. Some tree species have also encroached on big sagebrush habitat. For example, in the late 20th century, ''

Abies concolor ''Abies concolor'', the white fir, concolor fir, or Colorado fir, is a coniferous tree in the pine family Pinaceae. This tree is native to the mountains of western North America, including the Sierra Nevada and southern Rocky Mountains, and int ...

'' (white fir) was out-competing big sagebrush in Warner Mountains in California.

Galls

This species is host to the following insect induced galls: * '' Eutreta diana'' fly bud gall * '' Eutreta divisa'' fly bud gall * '' Eutreta oregona'' fly bud gall * '' Eutreta pollinosa'' fly bud? gall * '' Oxyna aterrima'' fly bud gall * ''Rhopalomyia (ampullaria, anthoides, brevibulla,calvipomum, conica, cramboides,culmata, florella, gossypina, hirticaulis, hirtipomum, lignea, lignitubus, mammilla, medusa, medusirrasa, nucula, obovata, occidentalis, pomum, rugosa, tridentatae, tubulus, tumidibulla, tumidicaulis)'' Various gall midges
external link to gallformers
Eutreta diana 1.jpg, ''Eutreta diana'' Rhopalomyia calvipomum.jpg, ''Rhopalomyia calvipomum'' Rhopalomyia conica 1.jpg, ''Rhopalomyia conica'' Rhopalomyia pomum gall.jpg, ''Rhopalomyia pomum'' Rhopalomyia_medusa_1.jpg, ''Rhopalomyia medusa''

Uses

The Cahuilla used to gather large quantities of sagebrush seed and grind it to make flour. The main modern use is as firewood, with the wood's oils being particularly flammable.

Medicinal

The plant's active medicinal constituents include camphor, terpenoids, and

tannin Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and Precipitation (chemistry), precipitate proteins and various other organic compounds including amino acids and alkaloids. The term ''tannin'' is widel ...

s. It is used as a

herbal medicine Herbal medicine (also called herbalism, phytomedicine or phytotherapy) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. Scientific evidence for the effectiveness of many herbal treatments ...

by Native Americans throughout the Intermountain West of North America, most notably as a smudging herb. It is also used for preventing infection in wounds, stopping internal bleeding, and treating

headache A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...

s and colds. The

Navajo The Navajo or Diné are an Indigenous people of the Southwestern United States. Their traditional language is Diné bizaad, a Southern Athabascan language. The states with the largest Diné populations are Arizona (140,263) and New Mexico (1 ...

use the vapors of sagebrush as a treatment for headache.''Edible and Medicinal Plants of the West'', Gregory L. Tilford, The

Okanagan The Okanagan ( ), also called the Okanagan Valley and sometimes the Okanagan Country, is a region in the Canadian province of British Columbia defined by the basin of Okanagan Lake and the Canadian portion of the Okanagan River. It is part of ...

and Colville people used sagebrush to smoke hides. Among the

Zuni people The Zuni (; formerly spelled ''Zuñi'') are Native American Pueblo peoples native to the Zuni River valley. The Zuni people today are federally recognized as the Zuni Tribe of the Zuni Reservation, New Mexico, and most live in the Pueblo o ...

, an infusion of the leaves is used externally for body aches. The infusion is also taken as a cold medicine. It is also placed in shoes to treat athlete's foot, fissures between toes, and as a foot deodorant.Camazine, Scott and Robert A. Bye 1980 A Study Of The Medical Ethnobotany Of The Zuni Indians of New Mexico" ''Journal of Ethnopharmacology'' 2:365–88 (p. 374)

Culture

''Artemisia tridentata'' is the state flower of

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

References

External links

* * *
GIS Database for Sage Grouse and Shrubsteppe Management in the Intermountain West

Jepson eFlora (TJM2) treatment of ''Artemisia tridentata''

The Sagebrush Sea
{{Taxonbar, from=Q2117903 tridentata Flora of the Northwestern United States Flora of the North-Central United States Flora of the Southwestern United States Flora of Western Canada Flora of the California desert regions Flora of the Great Basin Flora of New Mexico Flora of the Sierra Nevada (United States) Natural history of the California chaparral and woodlands Plants described in 1841 Plants used in traditional Native American medicine Forages Flora without expected TNC conservation status