• Wind Cave National Park - Two Worlds

    Wind Cave

    National Park South Dakota

Seed Study - Pascopyrum smithii

Pascopyrum smithii (Agropyron smithii) - Western Wheatgrass

Pascopyrum smithii (Agropyron smithii) - Western Wheatgrass

NPS Graphic

Species: Pascopyrum smithii (Agropyron smithii)
Common name: western wheatgrass

Vegetative identification: Emerges green with a very narrow spindly leaf, and gradually turns the distinctive blue-green color. The prominent veins and claw-like auricles are visible fairly early in growth. Seedlings are sometimes purplish or brown at the base and the emerging leaf often forms a corkscrew shape.

 
Picture of Pascopyrum smithii (Agropyron smithii) - Western Wheatgrass

NPS Photo

 

Pascopyrum smithii – western wheatgrass
Average number of good seeds per gram bulk matter: 15
Average number of good seeds per gram cleaned: 275
Commercial estimates of seeds per gram: 243; 300
Percent seed: 9.5
Percent live: n.m.
Collection dates: September 26; October 7 and 25
Collection effort: 370 gram in 14 person hours
Collection notes: Even though this species is a dominant grass in the park, in 2004 when we were trying to collect seed for the project we found no plants producing seed and very few even flowering. It was assumed this was because of drought. The seed used in the project was collected on private and Forest Service lands south of Custer SD. Plants there that produced seed were generally in shaded areas or at the bases of rock outcrops where moisture may have accumulated.
Cleaning notes: Bulk measurement included stems, leaves, lemmas, glumes, etc. Clean seed measurement was hard seed with a small amount of lemma and glume.

Did You Know?

American bison on the Wind Cave National Park prairie

The American bison is the largest terrestrial mammal in North America. Male bison can weigh a ton and can run 35 miles per hour. Do not approach bison. They weigh more and can outrun you. More...