North America Non-native Plant

Elymus Longearistatus

Botanical name: Elymus longearistatus

USDA symbol: ELLO4

Habit: grass

Native status: Not native but doesn't reproduce and persist in the wild

Synonyms: Agropyron longearistatum (Boiss.) Boiss. (AGLO3)   

Elymus longearistatus: The Mystery Grass You Probably Shouldn’t Plant Ever stumbled across a plant name that sounds intriguing but leaves you scratching your head when you try to find information about it? Meet Elymus longearistatus, a grass species that’s about as elusive as a gardener’s perfect watering schedule. While this ...

Elymus longearistatus: The Mystery Grass You Probably Shouldn’t Plant

Ever stumbled across a plant name that sounds intriguing but leaves you scratching your head when you try to find information about it? Meet Elymus longearistatus, a grass species that’s about as elusive as a gardener’s perfect watering schedule. While this member of the grass family (Poaceae) might sound impressive with its scientific nomenclature, it’s one of those plants that falls into the proceed with extreme caution category.

What We Know (Spoiler Alert: It’s Not Much)

Elymus longearistatus belongs to the wildrye grass genus, and like its grass relatives, it would theoretically be a graminoid – that’s fancy talk for grass-like plants. The species has a synonym, Agropyron longearistatum, which suggests it may have been reclassified at some point in botanical history. Beyond these basic taxonomic details, reliable information about this particular species is surprisingly scarce.

The Problem with Mystery Plants

Here’s where things get tricky for home gardeners. When a plant species lacks readily available information about:

  • Its native range and habitat requirements
  • Growth characteristics and mature size
  • Invasive potential in different regions
  • Cultivation needs and hardiness zones
  • Ecological benefits for local wildlife

It becomes nearly impossible to make informed gardening decisions. Without knowing where Elymus longearistatus naturally occurs, we can’t determine if it’s appropriate for your local ecosystem or if it might become problematic.

Why This Matters for Your Garden

Responsible gardening means choosing plants that:

  • Support local ecosystems and wildlife
  • Won’t escape cultivation and harm native plant communities
  • Are likely to thrive in your specific growing conditions
  • Come from reputable, sustainable sources

With Elymus longearistatus, we simply don’t have enough information to check any of these boxes confidently.

Better Alternatives: Well-Documented Native Grasses

Instead of gambling with an unknown species, consider these well-researched native grass alternatives that offer proven benefits:

  • Little bluestem (Schizachyrium scoparium) – A beautiful bunch grass with stunning fall color
  • Buffalo grass (Poaceae dactyloides) – Perfect for low-water landscapes
  • Purple lovegrass (Eragrostis spectabilis) – Creates lovely purple clouds when in bloom
  • Canada wildrye (Elymus canadensis) – A well-documented relative that supports wildlife

The Bottom Line

While Elymus longearistatus might sound exotic and appealing, the lack of available information makes it a poor choice for most gardeners. In the world of native gardening, knowledge is power – and without adequate information about a species’ behavior, requirements, and ecological impact, you’re essentially conducting an uncontrolled experiment in your backyard.

Stick with well-documented native grasses that have proven track records of supporting local ecosystems while providing the aesthetic and functional benefits you’re seeking. Your garden (and local wildlife) will thank you for making informed, responsible plant choices.

Elymus Longearistatus

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

Elymus L. - wildrye

Species

Elymus longearistatus (Boiss.) Tzvelev

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