Aristida purpurea Nutt.
Purple Threeawn, Purple 3-awn, Purple Three-awn, Red Threeawn
Poaceae (Grass Family)
USDA Symbol: arpu9
Often in large bunches, the culms and leaf blades of this grass rise 12-20 in. in height. The seedhead is narrow and nodding with lax, purplish branches. Three long, bristles occur from each flower.
From the Image Gallery
Plant CharacteristicsDuration: Annual
Root Type: Fibrous
Leaf Retention: Deciduous
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Shape: Linear
Leaf Venation: Parallel
Fruit Type: Caryopsis
Size Notes: Low tufted culms 25-70 cm. tall.
Autumn Foliage: yes
Bloom InformationBloom Color: Purple
Bloom Time: Apr , May , Jun , Jul , Aug , Sep , Oct
DistributionUSA: AR , AZ , CA , CO , IA , ID , IL , KS , LA , MN , MT , NC , ND , NE , NM , NV , OK , OR , SC , SD , TX , UT , WA , WY
Canada: AB , SK
Native Distribution: Throughout Texas north to Utah, Colorado and Kansas, south to northern Mexico.
Native Habitat: Sun, open ground, well-drained sand, clay, loam, limestone; Overgrazed ranges, disturbed roadsides, abandoned fields.
Growing ConditionsWater Use: Low
Light Requirement: Sun
Soil Moisture: Dry
CaCO3 Tolerance: High
Drought Tolerance: High
Soil Description: Dry, rocky soils.
Conditions Comments: With a gentle breeze passing through purple three-awn inflorescences (grass flowers), a dreamer can imagine that the earth has purple hair. This low-growing prairie grass is good for erosion control on banks and provides a root matrix for many wildflower species. Purple three-awn is an early successional species.
BenefitUse Wildlife: Seldom grazed. The seeds are food for some song birds, like the Junco. The plants provide nesting materials or habitat for some fur and game animals.
Conspicuous Flowers: yes
Interesting Foliage: yes
Larval Host: Skippers, Satyrs
Deer Resistant: High
Value to Beneficial InsectsProvides Nesting Materials/Structure for Native Bees
This information was provided by the Pollinator Program at The Xerces Society for Invertebrate Conservation.
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Find seed sources for this species at the Native Seed 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...
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From the National Organizations DirectoryAccording to the species list provided by Affiliate Organizations, this plant is on display at the following locations:
Lady Bird Johnson Wildflower Center - Austin, TX
Santa Barbara Botanic Garden - Santa Barbara, CA
Brackenridge Field Laboratory - Austin, TX
Nueces River Authority - Uvalde, TX
Native Seed Network - Corvallis, OR
Jacob's Well Natural Area - Wimberley, TX
Herbarium Specimen(s)NPSOT 0356 Collected May 19, 1993 in Bexar County by Louise Morrell
Wildflower Center Seed BankLBJWC-89 Collected 2003-05-13 in Travis County by Lady Bird Johnson Wildflower Center
BibliographyBibref 946 - Gardening with Prairie Plants: How to Create Beautiful Native Landscapes (2002) Wasowski, Sally
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Additional resourcesUSDA: Find Aristida purpurea in USDA Plants
FNA: Find Aristida purpurea in the Flora of North America (if available)
Google: Search Google for Aristida purpurea
MetadataRecord Modified: 2019-03-28
Research By: TWC Staff