North America Native Plant

Achnatherum ×bloomeri

Botanical name: Achnatherum ×bloomeri

USDA symbol: ACBL

Life cycle: perennial

Habit: grass

Native status: Native to the lower 48 states  

Synonyms: Oryzopsis bloomeri (Bol.) Ricker (ORBL)  ⚘  Stipa bloomeri Bol. (STBL4)  ⚘  Stiporyzopsis bloomeri (Bol.) B.L. Johnson (STBL5)   

Achnatherum ×bloomeri: A Lesser-Known Native Western Grass Meet Achnatherum ×bloomeri, a native perennial grass that’s more of a botanical mystery than a garden center staple. If you’ve never heard of this plant, you’re not alone – it’s one of those fascinating native species that flies under the radar in the ...

Achnatherum ×bloomeri: A Lesser-Known Native Western Grass

Meet Achnatherum ×bloomeri, a native perennial grass that’s more of a botanical mystery than a garden center staple. If you’ve never heard of this plant, you’re not alone – it’s one of those fascinating native species that flies under the radar in the gardening world.

What Exactly Is Achnatherum ×bloomeri?

This perennial grass belongs to the graminoid family, which is botanist-speak for grass-like plants. The × in its name is your clue that this is a hybrid species – nature’s own plant breeding experiment. You might also see it listed under its historical names like Oryzopsis bloomeri or Stipa bloomeri, as botanists have shuffled it around the classification system over the years.

As a true native of the American West, this grass calls the lower 48 states home, specifically thriving across eleven western states including Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming.

The Garden Reality Check

Here’s where things get interesting (and a bit disappointing for eager native plant gardeners): Achnatherum ×bloomeri is rarely found in cultivation. Unlike its more famous grass cousins, this species hasn’t made the jump from wild landscapes to garden centers. This means you won’t find growing guides, care instructions, or nursery sources readily available.

Why the Mystery?

Several factors contribute to this plant’s low profile in the gardening world:

  • Limited research on cultivation requirements
  • Unclear propagation methods
  • Unknown garden performance and aesthetic appeal
  • Lack of commercial availability

What This Means for Native Plant Enthusiasts

If you’re passionate about growing western native grasses, you might need to look elsewhere for now. Instead, consider these well-documented native alternatives that offer similar ecological benefits:

  • Blue grama (Bouteloua gracilis)
  • Buffalo grass (Poaceae dactyloides)
  • Western wheatgrass (Pascopyrum smithii)
  • Needle-and-thread grass (Hesperostipa comata)

The Bottom Line

While Achnatherum ×bloomeri represents an authentic piece of western American flora, it remains more of a botanical curiosity than a practical garden choice. Its native status across eleven western states suggests it plays an important ecological role in wild landscapes, but until more research emerges about its cultivation needs and garden performance, it’s likely to remain a specialist’s plant rather than a mainstream garden addition.

Sometimes the most interesting native plants are the ones that keep their secrets – and Achnatherum ×bloomeri is definitely one of those enigmatic species that reminds us there’s still so much to discover about our native flora.

Achnatherum ×bloomeri

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

Achnatherum P. Beauv. - needlegrass

Species

Achnatherum ×bloomeri (Bol.) Barkworth [hymenoides × occidentale]

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