Trees to 40m (usually much shorter in North America); trunk to 0.6m diam. (usually less in North America), straight or contorted, erect or leaning; crown broad-conic to irregular or flattened. Bark ashy gray to brown, furrowed, ridges irregularly rectangular, scaly, orange on upper sections of trunk, platy. Branches spreading to ascending, poorly self-pruning; twigs slender, dull green- to orange-brown, not glaucous, aging gray-brown, rough. Buds conic-ovoid, red-brown, 0.6--1.1cm, resinous. Leaves 2 per fascicle, spreading to ascending-upcurved, persisting 2--4 years, 4--6(--8)cm ´ 2mm, strongly twisted, somewhat flattened, blue- to gray- or yellow-green, all surfaces with evident stomatal lines, margins entire to finely serrulate, apex acute to abruptly acuminate; sheath 0.3--0.6cm, base semipersistent. Pollen cones ovoid, to 10mm, yellow or pale pink. Seed cones maturing in 2 years, shedding seeds and mostly falling soon thereafter, nearly symmetric, narrowly ovoid or lanceoloid before opening, broadly ovoid to depressed-globose when open, 3--6cm, dull gray-brown to tan or greenish gray, nearly sessile or on stalks to 1cm, scales lacking contrasting border on adaxial surface distally; apophyses slightly raised, isodiametric, 4-keeled, more elongate abaxially toward cone base; umbo central, raised to depressed, truncate, mostly umbilicate, unarmed. Seeds asymmetrically obovoid; body 3--5mm, gray to near black; wing to 15mm.

Pinus sylvestris is a Eurasian species widely planted and escaping from cultivation over much of northern United States and southern Canada. Representatives of the species in the flora originated from mostly poor seed stock of var. sylvestris . They are not much used for timber (as the tree is in Europe and Asia, where several varieties are known) but are used for pulpwood and Christmas trees.