North America Native Plant

Southern Threeawn

Botanical name: Aristida simpliciflora

USDA symbol: ARSI3

Life cycle: perennial

Habit: grass

Native status: Native to the lower 48 states  

Southern Threeawn: A Delicate Native Grass Worth Getting to Know If you’re looking to add some authentic southeastern charm to your native garden, meet the southern threeawn (Aristida simpliciflora). This understated perennial grass might not steal the show like flashier wildflowers, but it brings its own quiet elegance to the ...

Rare plant alert!

Region: Alabama

Status: S3S4: Status is uncertain but is somewhere between the following rankings: Vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 10,000 individuals ⚘ Critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘

Region: Alabama

Southern Threeawn: A Delicate Native Grass Worth Getting to Know

If you’re looking to add some authentic southeastern charm to your native garden, meet the southern threeawn (Aristida simpliciflora). This understated perennial grass might not steal the show like flashier wildflowers, but it brings its own quiet elegance to the landscape while supporting local ecosystems.

What Makes Southern Threeawn Special?

Southern threeawn is a native perennial grass that calls the southeastern United States home. You’ll find this graceful grass naturally growing across Alabama, Florida, Georgia, Mississippi, and North Carolina, where it has adapted perfectly to the regional climate and soils.

What sets this grass apart is its delicate, three-awned seed heads that dance in the breeze, creating subtle movement and texture in the garden. The fine foliage forms neat clumps that work beautifully as accent plants or when massed for a naturalized look.

Important Considerations: Rarity Status

Here’s something important to know: southern threeawn is considered rare in Alabama, with a conservation status of S1. This means if you’re planning to add this grass to your garden, it’s crucial to source it responsibly. Always purchase from reputable native plant nurseries that propagate their own stock rather than wild-collecting. Never harvest seeds or plants from wild populations.

Where Southern Threeawn Shines in Your Landscape

This native grass is perfect for:

  • Native plant gardens and prairie restorations
  • Coastal and sandy soil landscapes
  • Wildlife-friendly gardens
  • Low-maintenance naturalized areas
  • Accent plantings among other native species

Southern threeawn has a facultative wetland status in the Atlantic and Gulf Coastal Plain region, meaning it’s adaptable and can thrive in both wetland and upland conditions. This versatility makes it a great choice for gardens with varying moisture levels.

Growing Southern Threeawn Successfully

The good news? This native grass is refreshingly low-maintenance once you understand its preferences.

Climate Requirements: Southern threeawn thrives in USDA hardiness zones 8-10, making it well-suited for the warm, humid conditions of the Southeast.

Soil and Sun Needs: This grass loves full sun and performs best in sandy, well-draining soils. It’s naturally drought-tolerant once established, making it an excellent choice for low-water gardens.

Planting Tips:

  • Plant in spring or early fall for best establishment
  • Space plants 12-18 inches apart for individual specimens
  • Water regularly during the first growing season, then reduce watering
  • Minimal fertilization needed – this grass prefers lean soils

Care and Maintenance: Once established, southern threeawn is remarkably self-sufficient. Cut back in late winter before new growth emerges. The grass will naturally self-seed in favorable conditions, though seed production may be light.

Wildlife and Ecosystem Benefits

While southern threeawn is wind-pollinated and doesn’t directly attract pollinators like flowering plants do, it plays an important role in the ecosystem. Native grasses provide habitat for beneficial insects, nesting material for birds, and help support the complex web of native wildlife.

The seeds, though small, can provide food for small birds and other wildlife, while the grass structure offers shelter and overwintering sites for beneficial insects.

The Bottom Line

Southern threeawn is a wonderful choice for gardeners who appreciate subtle beauty and want to support native ecosystems. Its low-maintenance nature and adaptability make it suitable for both novice and experienced native plant gardeners. Just remember to source responsibly due to its rarity status, and you’ll have a lovely native grass that truly belongs in your southeastern landscape.

If you can’t find southern threeawn from responsible sources, consider other native Aristida species or southeastern native grasses like little bluestem or Gulf muhly as alternatives that offer similar benefits with less conservation concern.

Southern Threeawn

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Poaceae Barnhart - Grass family

Genus

Aristida L. - threeawn

Species

Aristida simpliciflora Chapm. - southern threeawn

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA