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Native Plant Society of Texas

Prairie Wedgescale

Sphenopholis obtusata

Other common name(s):

Prairie Wedgegrass

Family:

Poaceae (Grass Family)

Plant Ecoregion Distribution Map

This map uses data from the US EPA. EPA  servers have been offline frequently so maps may not display. We are working on a solution.

Chihuahuan Deserts, Cross Timbers, East Central Texas Plains, Edwards Plateau, Gulf Coast Prairies and Marshes, Southern Texas Plains, Texas Blackland Prairies, Western Gulf Coastal Plain
Chihuahuan Desert Grasslands
Grand Prairie
Bastrop Lost Pines, Floodplains and Low Terraces2, Northern Post Oak Savanna, Northern Prairie Outliers, San Antonio Prairie, Southern Post Oak Savanna
Balcones Canyonlands, Llano Uplift
Laguna Madre Barrier Island and Coastal Marshes, Mid-Coast Barrier Islands and Coastal Marshes, Northern Humid Gulf Coastal Prairies, Texas-Louisiana Coastal Marshes
Semiarid Edwards Bajada
Floodplains and Low Terraces1, Northern Blackland Prairie, Southern Blackland Prairie
Flatwoods, Floodplains and Low Terraces3, Pleistocene Fluvial Terraces, Red River Bottomlands, Southern Tertiary Uplands, Tertiary Uplands

Plant Characteristics

Growth Form

Grass & Sedge

Height

1
to
3
ft.

Spread

1
to
2
ft.

Leaf Retention

Deciduous

Lifespan

Annual

Habitat and Care Requirements

Soil Type(s)

Clay, Moist

Light Requirement

Sun, Part Shade

Water Requirement

Medium

Native Habitat

Grassland, Woodland

Bloom and Attraction

Bloom Color

Green

Bloom Season

Summer

Seasonal Interest

Nectar, Pollen

Wildlife Benefit

Butterflies

Maintenance

A cool season, clump forming grass. Adaptable to many sites. Roots should not be allowed to be perpetually dry or flooded. This species establishes well in recently disturbed areas, therefore it can be a good competitor with non-native species. A hardy species that can be used to fill empty spaces in native plant gardens. It behaves as an annual or short-lived perennial. The fibrous roots hold soil but do not colonize. Propagation: seed.

Comments

Blooms March-May. A cool-season grass. Foliage will lean gracefully to one side as the plant sets seed. The inflorescence is a layered spike. It will change from pale green in the spring to an oatmeal-tan color when it is mature. The seed spikelet will sometimes turn an attractive purple color.
Previous Scientific Name(s): Aira obtusata, Sphenopholis obtusata var. lobata, Sphenopholis obtusata var. pubescens

References

Learn about how to propagate Texas native plants.

Material Treatment Method Collection References
Seed No Treatment Can be sown directly in the soil outdoors. Seeds germinate after sowing in a warm location. When direct sowing, space the seeds 6-12 inches apart and lightly cover them with soil. If starting indoors, use seed starting trays and place them in a sunny window or under grow lights. Keep the soil consistently moist but not waterlogged. Germination typically takes 1-2 weeks, but can vary depending on temperature and soil conditions. Once your seedlings emerge, thin them to allow for proper spacing. The seeds mature in late summer or early fall. Look for the seed heads turning brown and ready to shed their seeds. Carefully collect these seed heads and store them in a cool, dry place until you’re ready to plant. 1) https://www.prairiemoon.com/sphenopholis-obtusata-prairie-wedgegrass#panel-planting 2) https://propagate.one/how-to-propagate-sphenopholis-obtusata/
Seed Scarification You can scarify your seeds by gently rubbing them against coarse sandpaper or placing them in a bowl of boiling water for a few minutes, followed by an immediate ice water bath. Keep the soil consistently moist but not waterlogged. Germination typically takes 1-2 weeks, but can vary depending on temperature and soil conditions. Once your seedlings emerge, thin them to allow for proper spacing. The seeds mature in late summer or early fall. Look for the seed heads turning brown and ready to shed their seeds. Carefully collect these seed heads and store them in a cool, dry place until you’re ready to plant. https://propagate.one/how-to-propagate-sphenopholis-obtusata/

About the Region

Fall Symposium 2025 Logo - Teach for the Future

Salado, the location of our Fall 2025 Symposium, lies at the intersection of two ecoregions: the Edwards Plateau (Limestone Cut Plain) and Blackland Prairie (Northern Blackland Prairie).

The Edwards Plateau area is also called the Hill Country; however, this general term covers a much larger area extending farther north. Spring-fed creeks are found throughout the region; deep limestone canyons, rivers, and lakes (reservoirs) are common. Ashe juniper is perhaps the most common woody species found throughout the region. Additional woody species include various species of oak, with live oak (Quercus fusiformis) being the most common. Sycamores (Platanus occidentalis) and bald cypress (Taxodium distichum) border waterways. This area is well known for its spring wildflower displays, though they may be viewed in spring, late summer, and fall, as well. According to Texas Parks and Wildlife, average annual rainfall in the Edwards Plateau ranges from 15 to 34 inches.

The Blackland Prairie extends from the Red River south to San Antonio, bordered on the west by the Edwards Plateau and the Cross Timbers, and on the east by the Post Oak Savannah. Annual rainfall averages 30 to 40 inches, with higher averages to the east. This region is dominated by prairie species. The most common grass species include little bluestem (Schizachyrium scoparium) and Indian grass (Sorghastrum nutans) in the uplands and switchgrass (Panicum virgatum) in the riparian areas and drainages. Common herbaceous flowering plants include salvias, penstemons, and silphiums. This area has suffered greatly from overgrazing and agricultural use. Few intact areas remain, though many of the plants can be found along county roadsides throughout the region.

Our fall Symposium host chapter, the Tonkawa Chapter, includes both of these ecoregions.

Source: Wildflowers of Texas by Michael Eason