 Steve Hurst @ USDA-NCRS PLANTS Database
Image 1- A. confertifolia distribution
 Image 2- Courtesy of www.librarygarden.com A. confertifolia mature
 Photo courtesy Michael Aust et al Copyright 2007 Virginia Forestry Department
Image 3- A. confertifolia seeds
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 Mileu
Shadscale, also known as saltsage or saltbush, is a perennial evergreen shrub from the Amaranthaceae family that is found in the deserts of North America- specifically the United States: AZ, CA, CO, ID, MT, ND, NM, NV, OR, TX, UT, and WY (see photo 1). A. confertifolia is located in regions where the elevation ranges from 4,000 to 7,000 feet. These areas are typically arid, and receive 6 to 10 inches of annual precipitation; for this reason, Shadscale is prevalent in the Great Basin region. In comparing A. confertifolia of the Great Basin and Colorado Plateau, Great Basin species have “narrower leaves and darker spines”1, while plants of the Colorado Plateau have “larger leaves and lighter colored spines”1. Thus, there is some phenotypic variation of the species in differing geographic environments. Sandy soil, little water, and a saline environment are what this C4 plant is adapted to (although its life is relatively short-lived). Like many other Atriplex species, A. confertifolia acts as an alkali halophyte in the saline and alkaline environments in which it exists.
 Structure
A. confertifolia has a rounded, clustered, dense shape (see image 2)- indeed, it is a round bush. It may reach a height of 20-81 cm and a width of 30-173 cm. Branches are smooth and solid when young, but become “spine-like” with age. Fruit is housed in a small utricle (4-12 mm) that usually carries one seed. Seeds width varies from 1.5 to 2 mm. The roots of A. confertifolia are deep, forming extensive root networks. Significant density differences between A. confertifolia roots have been observed 75 cm under the surface of the soil2.
 Identification and Seeds
Leafs are 39 to 80 cm long and ovate in shape (see image 3); this species is easy to identify from other Atriplex which typically have linear leaves. Although the leaves of A. confertifolia are similarly shaped as those of Atriplex garretti (ovate) and thus easy to confuse, those of A. garretti are slightly shorter (20-60 cm long).
 Fire Resistance
A. confertifolia is not resistant to fires. Historically, it was not surrounded by vegetation that was fire-prone (seeded range grasses) that could be used as fire fuel; therefore, it did not adapt fire-resistant characteristics to survive and still lacks them even today. Hence, fires are promoted when this plant is present4. Such was the case with the fire in 1998 in which more than 11,330 ha of rangeland were burned on Dugway Proving Ground in the West Desert of Utah.
 Palpable Parts and Reproduction
The fruit of A. confertifolia does not have four wings like other Atriplex plants do, but instead has two wings in a “v” shape. Leaves and fruits provide winter food for regional herbivores and livestock. Mule deer, birds and even small mammals (i.e. jackrabbits) feed on its vegetation. Thick spines develop as twigs reach maturity and these spinous twigs restrict additional use by other animals. Establishment, revegetation, and complex mechanisms of dormancy are some of A. confertifolia’s greatest reproductive restrictions.
 Medicinal Purposes
A. confertifolia has been inhaled in smoke form for epilepsy treatment, boiled and used as a liniment for sore muscles and aches, and mashed leaves have been used on the chest to treat colds3. Drinking a decoction of the leaves has also been used to treat colds3.
Intellectual recognition goes to the following web sites for images and literature sources.
1-128. Sanderson, S. C.; Stutz, H. C.; McArthur, E. D. 1990. Geographic differentiation in Atriplex confertifolia. American Journal of Botany. 77(4): 490-498
2- Hodgkinson, Ken C.; Johnson, Pat S.; Norton, Brien E. 1978. Influence of summer rainfall on root and shoot growth of a cold-winter desert shrub, Atriplex confertifolia. Oecologia. 34: 353-362
3- Moerman. D. Native American Ethnobotany Timber Press. Oregon. 1998
4- Banner, Roger E. 1992. Vegetation types of Utah. Journal of Range Management. 14(2): 109-114
http://www.librarygarden.com/detailPlant.php?ID=10
http://www.wildflower.org/gallery/result.php?id_image=17986
http://www.pfaf.org/database/plants.php?Atriplex+confertifolia
http://plants.usda.gov/java/profile?symbol=ATCO
www.wikipedia.org
http://www.fs.fed.us/database/feis/plants/shrub/atrcon/all.html#BLM%20PHYSIOGRAPHIC%20REGIONS
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