18. Quercus myrtifolia Willdenow, Sp. Pl. 4(1): 424. 1805.
Trees or shrubs , evergreen, to 12 m. Bark gray and smooth distally, dark and shallowly furrowed near base. Twigs dark red-brown, 1-2.5(-3) mm diam., persistently pubescent, rarely almost glabrous. Terminal buds reddish to purplish brown, ovoid, 2-5.5 mm, glabrous or with tuft of tawny hairs at apex. Leaves: petiole 1-5 mm, glabrous, occasionally sparsely pubescent. Leaf blade elliptic to narrowly or broadly obovate, occasionally spatulate, 15-50(-70) × 10-25(-35) mm, base cuneate to rounded, margins entire, somewhat revolute, with 1-4 awns, apex obtuse or rounded; surfaces abaxially glabrous except for axillary tufts of tomentum, occasionally yellow-scurfy, adaxial surface planar, glabrous. Acorns biennial; cup saucer-shaped to shallowly goblet-shaped, 4-7 mm high × 8.5-14.5 mm wide, covering 1/4-1/3 nut, outer surface puberulent, inner surface half to fully pubescent, scale tips tightly appressed, acute; nut broadly ovoid to globose, 9.5-14 × 8-13 mm, glabrate, scar diam. 5-8 mm.
Flowering spring. Dunes, hammocks, sandhills, dry sandy ridges, and oak scrub; 0-100 m; Ala., Fla., Ga., Miss., S.C.
This species flowers one to two weeks earlier than Q . inopina (A. F. Johnson and W. G. Abrahamson 1982).
Quercus myrtifolia reportedly hybridizes with Q . incana (= Q . × oviedoensis Sargent), but E. J. Palmer (1948) questioned the identification of the type specimen; the brief description by Sargent suggests that the specimen may be from an individual of Q . inopina . D. M. Hunt (1989) cited evidence of hybridization with Q . arkansana , Q . hemisphaerica , Q . inopina , Q . laurifolia , Q . marilandica , Q . nigra , and Q . pumila (Hunt suggested that the last may give rise to occasional reports of annual fruiting in Q . myrtifolia ).