It is native to western North America from Alaska to California to Colorado, where it grows in moist habitat, often in forests.

Melica subulata is a main understory member of the Douglas-fir/Alaska oniongrass plant community, a rare plant association that occurs on the southern edge of Vancouver Island on the Strait of Georgia.

[2] This plant community once had a wider range, occurring also along the Puget Sound and in the Willamette Valley.

[2] Melica subulata is a rhizomatous perennial grass with clustered onionlike corms at the base of each stem.

The inflorescence is a narrow or spreading panicle of cylindrical, pointed spikelets which may be nearly 3 centimeters long.