Achnatherum thurberianum is a species of grass known by the common name Thurber's needlegrass. It is native to the western United States, where it occurs from Washington to California and east to Montana and Wyoming. This is a tufted perennial grass with erect stems reaching about 75 centimeters in maximum height. The tuft of stems may be circular in shape as the stems in the center die first. The inflorescence is a narrow panicle up to 15 centimeters long by 2.5 wide. The spikelet has a sharp tip and a long, hairy awn which may exceed 5 to 10 centimeters in length.