Plants short-lived perennials; cespitose, not mat-forming. Culms 10–65 cm, usually decumbent and geniculate, sometimes erect. Ligules 1–2 mm, obtuse to truncate, entire; blades 2–7 mm wide, flat, folded, or involute. Panicles 4–16 cm, compact to diffuse at maturity, linear to pyramidal, lower branches ascending to erect, spikelet-bearing nearly to the base; pedicels slightly to densely scabrous, often with tumid epidermal cells. Spikelets 3–6 mm, with 2–6 florets. Glumes rounded over the back, veins prominent to obscure, apices acute to obtuse; lower glumes 0.8–1.6 mm; upper glumes 1.2–2.3 mm; calluses with a few hairs; lemmas 1.8–3 mm, slightly to markedly coriaceous throughout, glabrous or with a few hairs near the base, backs rounded, 5-veined, veins obscure, midveins usually excurrent, sometimes ending at the margins, apices acute to obtuse, entire, apical margins smooth or with a few scattered scabrules; palea veins glabrous proximally, scabrous to shortly hispid near midlength, scabrous distally; anthers 0.6–1 mm. 2n = 28.
Puccinellia fasciculata is native to Europe. In the Flora region, it is found principally along the east coast, but it is also established at a few sites in Arizona and Utah, and has been reported from Nevada. All occurrences in the Flora region are probably the result of human introductions.