22. Pinus serotina Michaux, Fl. Bor.-Amer. 2: 205. 1803.
Pinus rigida Miller subsp. serotina (Michaux) R.T. Clausen; P. rigida var. serotina (Michaux) Hoopes
Trees to 21m; trunk to 0.6m diam., straight or more often crooked, commonly with adventitious sprouts; crown becoming ragged, thin, often broadly rounded or flat. Bark red-brown, irregularly furrowed and cross-checked into rectangular, flat, scaly plates. Branches spreading to ascending; twigs stout, orange- to yellow-orange, frequently glaucous, aging darker. Buds ovoid to narrowly ovoid, red-brown, 1--1.5(--2)cm, resinous. Leaves 3 per fascicle (to 5 in adventitious or disturbed growth), spreading to ascending, persisting 2--3 years, (12--)15--20(--21)cm ´ 1.3--1.5(--2)mm, slightly twisted, tufted at twig tips, straight, yellow-green, all surfaces with fine stomatal lines, margins serrulate, apex acuminate; sheath 1--2cm, base persistent. Pollen cones cylindric, to 30mm, yellow-brown. Seed cones maturing in 2 years, in some populations beginning to shed seeds then but more often variably serotinous, long-persistent, often whorled, symmetric, ovoid to lanceoloid before opening, broadly ovoid to nearly globose when open, 5--8cm, pale red-brown to creamy brown, sessile or on stalks to 1cm, scales with dark red-brown border on adaxial surface distally; apophyses slightly thickened, low, rhombic, low cross-keeled; umbo central, low-conic, with short, weak prickle, sometimes unarmed. Seeds ellipsoid, oblique at tip, somewhat compressed; body 5--6mm, pale brown, mottled darker or nearly black; wing to 20mm. 2 n =24.
Flatwoods, flatwoods bogs, savannas, and barrens; 0--200m; Ala., Del., Fla., Ga., Md., N.J., N.C., S.C., Va.
Pinus serotina is fire successional and sprouts adventitiously after crown fires. It is part of a distinct forest type including Taxodium distichum (Linnaeus) Richard, Nyssa biflora Walter, Magnolia virginiana Linnaeus, Persea sp., and Ilex sp. Of good form when protected from fire, P . serotina then much resembles P . taeda , with which it hybridizes naturally. It is of increasing importance as pulpwood.