Dry or moist soil in woods and fields, bogs, meadows, roadsides. Tufted perennial grass with fibrous roots. Borne in spikelets, the spikelets many in a loose panicle, the panicle branches divergent from the main axis, usually purple at maturity, the panicle up to 1 foot long, the branches of the panicle thread-like, rough to the touch.
Grains ellipsoid, smooth.
Gleason and Cronquist use Poaceae for the name of this family. This species is sometimes called ticklegrass.