Join / Renew / Gift Donate Shop Member Portal Language

Search
npsot_bluebonnet_full_color

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

Disturbed Areas, Grassland, Riparian

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. Native habitat: moist meadows, streambanks, and shores of ponds or lakes.

Description

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

2026 Fall Symposium Logo

This low-elevations region of Texas extends inland from the barrier islands, about 60 or so miles, and stretches from Brownsville to Louisiana. In total, it covers about 9.5 million acres, with a high point of 150 feet in elevation. More than 1000 species of plants can be found in this region. On the southern end, species more common in Mexico (such as Sabal mexicana) and Central America occur.

The barrier islands provide us with dune systems, and clay flats to the inland side, which have species found in these areas alone. Many plants here, such as Ipomoea pes-caprae (beach morning glory), can be found throughout tropical regions of the globe. I’ve encountered the same species on the beaches of Guam.

Once inland, vast marshes and wet prairies occur. Occasionally, oak (Quercus fusiformis) groves can be found. Common grasses include species of Bothriochloa, Paspalum, and Sporobolus; eastern gamagrass (Tripsacum dactyloides); and switchgrass (Panicum species). Many rivers and creeks cut through the Gulf Prairies, and along these riparian areas various species of trees, Sabal minor, and other plants adapted to clay soils can be found. Due to overgrazing, farming, and fire suppression, woody species such as mesquite (Prosopis glandulosa) and huisache (Acacia farnesiana), and invasive species such as chinaberry (Melia azedarach), Brazilian pepper (Schinus terebinthifolius), and Chinese tallow (Sapium sebiferum) have increased and displaced our native flora.

Source: Wildflowers of Texas by Michael Eason