North America Native Plant

Woollysheath Threeawn

Botanical name: Aristida lanosa

USDA symbol: ARLA6

Life cycle: perennial

Habit: grass

Native status: Native to the lower 48 states  

Synonyms: Aristida lanosa Muhl. ex Elliott var. macera Fernald & Grisc. (ARLAM)   

Woollysheath Threeawn: A Delicate Native Grass Worth Protecting If you’re looking to add some wispy, graceful texture to your native plant garden, woollysheath threeawn (Aristida lanosa) might just be the understated beauty you’ve been searching for. This perennial native grass brings a delicate, almost ethereal quality to landscapes while supporting ...

Rare plant alert!

Region: New Jersey

Status: S2: Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ New Jersey Highlands region ⚘ New Jersey Pinelands region ⚘ 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) ⚘ Endangered: In danger of extinction throughout all or a significant portion of its range. ⚘

Region: New Jersey

Status: Endangered, Listed Pinelands, Highlands Listed, S1: Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ New Jersey Highlands region ⚘ New Jersey Pinelands region ⚘ 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) ⚘ Endangered: In danger of extinction throughout all or a significant portion of its range. ⚘

Woollysheath Threeawn: A Delicate Native Grass Worth Protecting

If you’re looking to add some wispy, graceful texture to your native plant garden, woollysheath threeawn (Aristida lanosa) might just be the understated beauty you’ve been searching for. This perennial native grass brings a delicate, almost ethereal quality to landscapes while supporting local ecosystems—but there’s an important conservation story that comes with it.

What Makes Woollysheath Threeawn Special

Woollysheath threeawn is a charming native grass that forms neat clumps of fine-textured foliage topped with delicate, airy seed heads. The plant gets its common name from the woolly sheaths that wrap around the base of its leaves, giving it a distinctive fuzzy appearance that sets it apart from other native grasses.

This perennial graminoid typically reaches 1-3 feet in height and maintains a tidy clumping growth habit, making it perfect for adding vertical interest without overwhelming smaller garden spaces.

Where This Native Beauty Calls Home

Woollysheath threeawn is native to the lower 48 states, with a natural range spanning across the southeastern and south-central United States. You can find this grass naturally occurring in Alabama, Arkansas, Delaware, Florida, Georgia, Illinois, Louisiana, Maryland, Mississippi, Missouri, New Jersey, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, and West Virginia.

A Conservation Concern Worth Noting

Here’s where things get important: woollysheath threeawn is considered rare in several states. In New Jersey, it’s listed as Endangered with an S1 conservation status, while Arkansas has designated it as S2. This means the plant faces significant threats to its survival in these areas.

If you’re considering adding this grass to your garden, please only use responsibly sourced material. This means purchasing from reputable native plant nurseries that propagate their own plants rather than collecting from wild populations. Never collect seeds or plants from natural areas, as this can further threaten already vulnerable populations.

Why Grow Woollysheath Threeawn?

Despite its conservation concerns—or perhaps because of them—this grass offers several compelling reasons to include it in appropriate gardens:

  • Native authenticity: Perfect for prairie restorations and native plant gardens
  • Low maintenance: Once established, it requires minimal care
  • Drought tolerance: Thrives in well-drained, sandy soils
  • Textural interest: Adds delicate, wispy movement to plantings
  • Conservation value: Helps support local ecosystems and preserve genetic diversity

Growing Conditions and Care

Woollysheath threeawn is surprisingly easy to grow once you understand its preferences:

Sunlight: Thrives in full sun locations

Soil: Prefers sandy, well-drained soils but adapts to various soil types as long as drainage is good

Hardiness: Suitable for USDA zones 6-9

Water: Drought tolerant once established, making it perfect for xeriscape gardens

Planting and Establishment Tips

Getting woollysheath threeawn established is straightforward with the right approach:

  • Plant in fall for best establishment
  • Direct seeding works well if you can source seeds responsibly
  • Space plants 12-18 inches apart if using transplants
  • Water regularly the first season, then reduce watering as the plant establishes
  • Minimal fertilization needed—this grass prefers lean soils

Design Ideas and Garden Roles

Woollysheath threeawn shines in several garden settings:

  • Prairie and meadow gardens: Adds authentic native character
  • Native plant borders: Provides textural contrast to broader-leafed natives
  • Xeriscape designs: Perfect for low-water landscaping
  • Conservation gardens: Helps preserve rare native genetics

The Bottom Line

Woollysheath threeawn represents both an opportunity and a responsibility for native plant gardeners. While it’s a beautiful, low-maintenance grass that supports local ecosystems, its rare status in some areas means we must be thoughtful about how we source and grow it.

If you can obtain responsibly sourced plants or seeds, this delicate native grass makes a wonderful addition to sunny, well-drained gardens. Just remember—by choosing to grow rare native plants like woollysheath threeawn, you’re not just gardening; you’re participating in conservation.

Woollysheath 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 lanosa Muhl. ex Elliott - woollysheath threeawn

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