Straggling shrub 1-2.5 m, rarely arborescent and to 4 m; lvs firm, oblong or elliptic, 4-7 cm, half as wide, obtuse or acute, broadly cuneate to obtuse at base, finely serrate with broadly triangular to semicircular, abruptly acuminate teeth, rugose above, finely and
rather roughly hairy beneath; pedicels 5-10 mm, finely hairy; hypanthium pubescent; sep oblong, 2.5 mm, finely hairy; pet obovate, 5-6 mm, cuneate at base; fr glaucous, purplish-black to sometimes red or yellow, subglobose, 1.5 cm; stone turgid, truncate at base; 2n=16. Dunes and sandy soil near the coast; N.B. to Md., occasionally extending some distance inland; c. Mich. May. (P. gravesii, a single unusual clone-colony in Conn., with small, subrotund lvs)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.