North America Native Plant

Firethread Sedge

Botanical name: Carex scopulorum var. prionophylla

USDA symbol: CASCP

Life cycle: perennial

Habit: grass

Native status: Native to Canada âš˜ Native to the lower 48 states  

Synonyms: Carex miserabilis Mack. (CAMI11)  âš˜  Carex prionophylla T. Holm (CAPR13)   

Firethread Sedge: A Hardy Northwestern Native for Your Garden Meet the firethread sedge (Carex scopulorum var. prionophylla), a tough little perennial that’s perfectly at home in the rugged landscapes of the Pacific Northwest and northern Rocky Mountains. While it might not have the flashiest flowers in the garden, this native ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3?: Status is uncertain but is somewhere between the following rankings: Inexact rank: ⚘ Subspecies or variety is 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. ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Firethread Sedge: A Hardy Northwestern Native for Your Garden

Meet the firethread sedge (Carex scopulorum var. prionophylla), a tough little perennial that’s perfectly at home in the rugged landscapes of the Pacific Northwest and northern Rocky Mountains. While it might not have the flashiest flowers in the garden, this native sedge brings something equally valuable: reliable, low-maintenance ground cover that connects your landscape to the region’s natural heritage.

What Makes Firethread Sedge Special?

As a member of the sedge family, firethread sedge is what botanists call a graminoid – basically a grass-like plant that forms the backbone of many natural ecosystems. This perennial has earned its place in native plant circles for being incredibly hardy and well-adapted to challenging mountain conditions.

You might also see this plant listed under its synonyms Carex miserabilis or Carex prionophylla in older gardening references, but don’t let the scientific names intimidate you – this is one accommodating plant once you understand its needs.

Where Does Firethread Sedge Call Home?

This sedge is a true child of the North American mountains, naturally occurring across British Columbia, Idaho, Montana, and Washington. It’s native to both Canada and the lower 48 states, making it a great choice for gardeners wanting to support regional biodiversity.

Why Consider Firethread Sedge for Your Garden?

Here’s where firethread sedge really shines in the home landscape:

  • Low maintenance: Once established, it requires minimal care – perfect for busy gardeners
  • Native credentials: Supporting local ecosystems while reducing the need for fertilizers and excessive watering
  • Erosion control: Those fibrous roots help hold soil in place on slopes
  • Natural look: Creates authentic northwest mountain meadow vibes in your garden
  • Wildlife habitat: Provides cover and nesting material for small creatures

Perfect Garden Settings

Firethread sedge works beautifully in:

  • Native plant gardens and natural landscapes
  • Rock gardens and alpine-style plantings
  • Slope stabilization projects
  • Low-water or xeriscaped areas
  • Transitional zones between cultivated and wild spaces

Growing Conditions and Care

Based on its natural mountain habitat, firethread sedge likely prefers:

  • Sun exposure: Full sun to partial shade
  • Soil: Well-draining soils, including rocky or sandy conditions
  • Water: Moderate moisture, but drought-tolerant once established
  • Climate: Hardy in USDA zones 3-7, perfect for cooler mountain climates

The beauty of native sedges like this one is that they’ve evolved to thrive in your local conditions without fuss. Once planted, they typically need little beyond occasional watering during establishment.

Planting Tips for Success

  • Plant in spring or early fall for best establishment
  • Space plants according to your coverage goals – they’ll naturally spread over time
  • Water regularly the first year, then reduce as the plant establishes
  • No fertilizer needed – these mountain natives prefer lean soils
  • Divide clumps every few years if you want to spread them around your garden

A Note on Responsible Sourcing

Since firethread sedge has a somewhat uncertain conservation status, it’s important to source your plants from reputable native plant nurseries rather than collecting from the wild. This ensures you’re supporting conservation efforts while adding authentic regional character to your landscape.

The Bottom Line

Firethread sedge might not be the showiest plant in the nursery, but it’s exactly the kind of steady, reliable native that makes gardens both beautiful and ecologically meaningful. If you’re looking to create a low-maintenance landscape that celebrates the natural beauty of the Pacific Northwest and northern Rocky Mountains, this hardy sedge deserves a spot in your garden planning.

Plus, there’s something deeply satisfying about growing a plant that’s perfectly adapted to where you live – it’s gardening in harmony with nature, and firethread sedge makes that partnership remarkably easy.

Firethread Sedge

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

Cyperaceae Juss. - Sedge family

Genus

Carex L. - sedge

Species

Carex scopulorum T. Holm - mountain sedge

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