''Eriocoma occidentalis'' is a species of

grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...

known by the common name western needlegrass. It is native to western North America from

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

, and Arizona and in northeastern Mexico (Chihuahua), where it grows in many types of habitat. This is a tufting perennial bunchgrass forming tight clumps of erect stems up to about in maximum height, but sometimes much shorter. The hairlike leaves are less than a millimeter wide and may have rolled edges. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is up to long, with each hairy spikelet bearing an awn up to 4 or 5 centimeters long. The awn is kinked twice.

Subspecies

Three subspecies are accepted: *''Eriocoma occidentalis'' subsp. ''californica'' – Washington, Oregon, California, Nevada, Idaho, and Alberta *''Eriocoma occidentalis'' subsp. ''occidentalis'' – California *''Eriocoma occidentalis'' subsp. ''pubescens'' – British Columbia and Alberta to California, Arizona, Colorado, and northeastern Mexico (Chihuahua)

References

External links

Jepson Manual TreatmentUSDA Plants ProfilePhoto gallery
occidentalis Bunchgrasses of North America Native grasses of California Grasses of the United States Grasses of Canada Flora of the Sierra Nevada (United States) Plants described in 1871 {{Pooideae-stub