Host an Event Volunteer Join Tickets

Support the plant database you love!

Share

Plant Database

Search for native plants by scientific name, common name or family. If you are not sure what you are looking for, try the Combination Search or our Recommended Species lists.

Enter a Plant Name:
Or you can choose a plant family:
Pascopyrum smithii (Western wheatgrass)
Wasowski, Sally and Andy

Pascopyrum smithii

Pascopyrum smithii (Rydb.) Á. Löve

Western Wheatgrass

Poaceae (Grass Family)

Synonym(s): Agropyron molle, Agropyron smithii, Agropyron smithii var. molle, Agropyron smithii var. palmeri, Elymus smithii, Elytrigia smithii, Elytrigia smithii var. mollis

USDA Symbol: pasm

USDA Native Status: L48 (N), AK (I), CAN (N)

Western Wheatgrass is a 10-36 in., cool-season, sod-forming, perennial grass. Its dense, narrow, 3-6 in. spikes occur at the top of stout culms. The entire plant is often covered with a white coating, lending a silvery caste to its blue-green leaves. The leaves are less than a quarter inch wide and, when dry, roll up longitudinally to display prominent ridges on the tops.

This densely colonizing turf grass is commonly found in western North America in low-lying areas subject to seasonal poor drainage. During wet times, this grass becomes aggressive and can crowd out neighboring grasses and forbs. For this reason, and for its silvery blue-green leaves, Western Wheatgrass is favored for erosion control. It covers so thickly, however, that it is not the best choice for a wildflower meadow. It won't allow many other plants room.

 

From the Image Gallery

3 photo(s) available in the Image Gallery

Plant Characteristics

Duration: Perennial
Habit: Grass/Grass-like
Root Type: Fibrous
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Venation: Parallel
Inflorescence: Spike
Fruit Type: Caryopsis
Size Notes: Up to about 3 feet tall.
Leaf: Gray-green, blue-green, or silvery green

Bloom Information

Bloom Color: Yellow
Bloom Time: May , Jun

Distribution

USA: AK , AR , AZ , CA , CO , GA , IA , ID , IL , IN , KS , KY , MA , MI , MN , MO , MT , ND , NE , NH , NM , NV , NY , OH , OK , OR , SD , TN , TX , UT , WA , WI , WY
Canada: AB , SK
Native Distribution: Ont. to B.C., s. to KY, TX, AZ & e. of the Cascades to n.e. CA
Native Habitat: Hillsides; bottomlands; canyons; open woods; prairies; scrubland. Often in swales and ditches with seasonal poor drainage.

Growing Conditions

Water Use: Medium
Light Requirement: Sun , Part Shade
Soil Moisture: Moist
CaCO3 Tolerance: High
Drought Tolerance: High
Soil Description: Moist, alkaline clay, loam, sand.
Conditions Comments: Thrives in seasonal poor drainage and high-rainfall years, when it can become aggressive enough to crowd out many other grasses and forbs.

Benefit

Use Ornamental: A blue-green turf grass that can be mowed
Use Other: Widely used for erosion control
Attracts: Birds

Propagation

Propagation Material: Root Division , Seeds
Description: Increase is easiest by rhizome division. Seeds have poor germination.
Seed Treatment: A KNO3 enrichment enhances germination but is not necessary.
Commercially Avail: yes
Maintenance: If gets too aggressive, reduce water.

Find Seed or Plants

Order seed of this species from Native American Seed and help support the Wildflower Center.

Find seed sources for this species at the Native Seed Network.

View propagation protocol from Native Plants Network.

Mr. Smarty Plants says

Plants to stop erosion in Arizona
January 17, 2009
I'm looking for a plant to stop erosion; I have big wash outs that are starting to erode my yard so I guess I'm looking for deep rooting plants. I live south of Tucson, Arizona. If you can advise me...
view the full question and answer

National Wetland Indicator Status

Region:AGCPAKAWCBEMPGPHIMWNCNEWMVE
Status: FACU UPL FAC UPL FACU FACU FACU FACU
This information is derived from the U.S. Army Corps of Engineers National Wetland Plant List, Version 3.1 (Lichvar, R.W. 2013. The National Wetland Plant List: 2013 wetland ratings. Phytoneuron 2013-49: 1-241). Click here for map of regions.

From the National Organizations Directory

According to the species list provided by Affiliate Organizations, this plant is on display at the following locations:

Texas Parks and Wildlife Department - Austin, TX
Native Seed Network - Corvallis, OR

Bibliography

Bibref 946 - Gardening with Prairie Plants: How to Create Beautiful Native Landscapes (2002) Wasowski, Sally
Bibref 841 - Native Alternatives to Invasive Plants (2006) Burrell, C. C.
Bibref 318 - Native Texas Plants: Landscaping Region by Region (2002) Wasowski, S. & A. Wasowski

Search More Titles in Bibliography

Web Reference

Webref 38 - Flora of North America (2019) Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.

From the Archive

Wildflower Newsletter 1989 VOL. 6, NO.4 - Spring Climbs Rockies Slowly, Colorado Cooler, Conference of Wildflower and Nati...

Additional resources

USDA: Find Pascopyrum smithii in USDA Plants
FNA: Find Pascopyrum smithii in the Flora of North America (if available)
Google: Search Google for Pascopyrum smithii

Metadata

Record Modified: 2023-01-25
Research By: TWC Staff

Go back