This is widely scattered in mesic woods on fertile soils in eastern states, but concentrated from mid-Atlantic to Ozarkian regions (K). P. sylvestris often grows near pratensis and can be confused, but it occurs mostly in deeper shade of woodland remnants, often associated with Carex jamesii (as in a few shady pre-1920 backyards of Lexington in FAYE). P. sylvestris is distinguished from pratensis by the absence of extensive rhizomes (versus present); larger blades tend to be broader (mostly 2-4 mm versus 1-3 mm), lax and horizontally spreading (versus moderately firm to involute, ascending); lower inflorescence branches are eventually reflexed (versus just widely spreading), often (?) densely scabrid (versus smooth to densely scabrid), and they tend to have fewer spikelets (1-11 versus 4-30); spikelets remain mostly plain green, contrasting with pale scarious margins when dried (versus bluish-green to more generally pale when dried), smaller (mostly 2.5-4.5 mm long versus 3.5-6 mm), with fewer florets (2-3 versus 2-5) and smaller lemmas (mostly 2-3.2 mm long versus 2-4.5 mm); 2n = 28 (versus 27-147).