Western wheatgrass

A blue-green prairie grass whose underground rhizomes weave a tough sod — the official state grass of North and South Dakota.

Western wheatgrass at a glance

Pascopyrum smithii PASS-koh-PY-rum SMITH-ee-eye

Type
Plant · grasses
Diet
Producer
Size
Grows 1 to 3 feet tall, about knee to waist height on a kid, with a bristly seed spike 2 to 6 inches long, about the length of a crayon box.
Lifespan
A long-lived perennial; a single patch of rhizomes can hold the same ground for many years.
Conservation
Not formally assessed by IUCN; common and secure across the Great Plains and Rocky Mountain West

A green plant that makes its own food from sunlight. Its strong, spreading underground stems, called rhizomes, store water and food below ground through drought and winter.

Is it safe to touch?

Harmless. No thorns, no poison. It's a grass you can walk through and run your hand across.

A watershed dam in Kansas took 14 inches of rain in a single storm and was overtopped. The earth held. USDA researchers name the reason: a stand of western wheatgrass growing on the dam, a grass most people would walk past without a second look, spreading its roots through the dirt tightly enough to keep the whole structure from washing out.

The trick is underground. Western wheatgrass spreads by rhizomes, tough stems that run sideways beneath the soil and send up new shoots as they go, weaving themselves into a dense sod. Above ground it looks like an ordinary blue-green grass, knee to waist high, with a stiff seed spike about the length of a crayon box. Below ground it is a woven mat strong enough to survive drought, hard freezes, salty soil, and, on that Kansas dam, a flood.

Both North Dakota and South Dakota looked at that same grass and made the identical decision: each state named it, separately, its official state grass. Walk the mixed-grass prairie at Badlands, Wind Cave, or Theodore Roosevelt and you are standing on the plant both states picked to represent them, holding the ground exactly the way it held that dam.

Did you know?

  • A patch of western wheatgrass once helped hold a Kansas watershed dam together when 14 inches of rain in a single storm overtopped it.
  • It is the official state grass of both North Dakota (1977) and South Dakota (1970), the same species claimed twice.
  • Its bluish, coarse-veined leaves earned it the nickname bluestem wheatgrass, even though it belongs to a different grass group than true bluestems.

Common questions

What does western wheatgrass look like?

A blue-green grass, 1 to 3 feet tall, with coarse leaves and a stiff, narrow seed spike. Its bluish color earned it the nickname bluestem wheatgrass.

Why is western wheatgrass good at stopping erosion?

Its underground rhizomes spread out and weave together into a tough sod. That mat of roots held together well enough to help save a Kansas dam during a major storm.

Is western wheatgrass a state symbol?

Yes. It's the official state grass of both North Dakota and South Dakota.

Do animals eat western wheatgrass?

Elk and cattle graze on it most of the year, and deer eat it in spring. Ranchers also plant it on purpose as livestock forage.

Where it lives

Where we got this