Luzula spp have a spikelike, pan-like, or umbellate inflorescence. Perianth is greenish to brown or purplish-brown, and often scarious. They are generally shiny, have 6 stamens, their caps are one celled, 3 seeded and are generally attached by cottony fibers, sometimes with a caruncle. They are a "grasslike" perennial herb that has closed leaves that are flat blades, fringed with small hairs.  One native western "woodrush" species found in the south Puget Sound glacial outwash prairies is Luzula comosa
Seed sample from: 2008
Average Measurement: 1.5 x 0.9 x 0.9
Measurement Range: L: 1.2 – 1.8, W: 0.8 – 1, D:0.8 – 1
Shape: Seeds have prominent white caruncle. Seed mostly round except for a slightly pointed tapering at hilum and opposite apex.
Color: Seed coat is white over a dark reddish brown seed body.
Surface: On one side of seed there is a cloudy white line that crosses from hilum to opposite apex. Seed is lustrous and marked with many fine longitudinal lines.
- Hitchcock and Cronquist "Flora of the Pacific Northwest"