Plants forming dense, extensive colonies, 1-3 dm; twigs of current season green to glaucous, ± angled, glabrous or hairy. Leaves deciduous; blade dark to pale green or glaucous, elliptic to narrowly elliptic, 15-41 × (5-)6-16(-20) mm, margins usually sharply, uniformly serrate (serrations sometimes minute, tipped with stipitate gland), surfaces glabrous or hairy, especially along abaxial midvein, eglandular abaxially. Flowers: calyx green, glaucous, glabrous; corolla usually white, cylindric to urceolate, 4-6 mm; filaments ciliate; (tubules with introrse, elongate pores). Berries black or blue, rarely white, 3-12 mm diam., glabrous. Seeds (3-)10-15(-20), ca. 1.2 mm. 2n = 48. Flowering spring-early summer. Headlands, high moors, dry, sandy areas, peaty barrens, rocky outcroppings, pine barrens, oak parklands, regeneration forests, abandoned pastures and bogs; 0-1900 m; St. Pierre and Miquelon; Man., N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que.; Conn., Del., Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., Tenn., Vt., Va., W.Va., Wis. Vaccinium angustifolium is extensively harvested from cultivated and wild plants in New England (especially Maine) and in Quebec and the Canadian Maritime Provinces.
From Flora of Indiana (1940) by Charles C. Deam
Erect or ascending shrubs, usually 10-20 inches high. Its preferred habitat is sandy white oak, black and white oak, and pin and black oak woods. It is usually associated with dryland blueberry. [Deam also recognized V. angustifolium var. nigrum, a form with leaves glaucous beneath but fruit lacking a bloom. About this variety he says:] I studied for two successive years, both in flower and in fruit, a large colony of this variety in Starke County, growing in an acre or more of shrubs of the typical species. The following differences were noted. The leaves were more or less glaucous, both on unfolding and at fruiting time; the corolla was about 0.5 mm wider; and the fruit longer than wide, and black with little or no bloom. I collected this variety also in La Porte County.
Shrubs 1-6 dm, extensively colonial; lvs deciduous, ±elliptic, mostly (1-)1.5-3 cm, a third to half as wide, sharply serrulate, green and glabrous (or with a few hairs along the veins) to less often glaucous; cal and pedicel often glaucous; cor cylindric to urceolate, 4-6 mm; fr blue-glaucous or less often black, 5-10 mm; 2n=48. Moist or dry, sandy or rocky soil, often in burned-over sites; Lab. and Nf. to Man., s. to N.J., Pa., Ill., and Minn., and in the mts. to N.C. (V. brittonii; V. lamarckii; Cyanococcus a.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.