Needle Grass (Stipa)

By Bruce Homer-Smith

Stipa is the primary California genus in the Needlegrass Tribe.

California’s needle grasses have distinctive characters:

· They’re bunch grasses with narrow, branched inflorescences.

· Spikelets have a single cylindrical floret, commonly with an awn from 1/8” to 9” long, sometimes bent.

· The floret is membranous to rigid.

· Glumes are membranous and long enough to hide the floret.

Here are some examples:

Purple Needle Grass (Stipa pulchra)

Drawing © John Muir Laws

Foothill Needlegrass (Stipa lepida)

Illustrated Flora of the Pacific States

King’s Ricegrass (Stipa kingii)

Photo by Steve Matson

Little Ricegrass (Stipa exigua)

Photo by Steve Matson

The top photos are classic, native needle grass species, widespread in California. The rice grasses below are also natives but with smaller spikelets and awns.

Leaf sheaths are open. Ligules have fine hairs on their edges.

Parish’s Needlegrass (Stipa parishii var. parishii)

Photo by Keir Morse

California has 31 species of Stipa. They fall into two groups – needle grasses with their needle look, and rice grasses that resemble true rice (Oryza).

Corrections/Comments: bruce@PlantID.net