Plants 30-60(-100+) cm. Stems proximally piloso-hirsute (hairs 1-3+ mm), distally stellate-pubescent and stipitate-glandular, sometimes piloso-hirsute as well (hairs 1-2+ mm). Leaves: basal 3-8+, cauline 1-5+; blades (often purple-mottled) lance-elliptic to lanceolate, 50-100 × 10-50+ mm, lengths 2-5 times widths, bases usually cuneate, sometimes rounded to truncate, margins ± dentate or entire, apices acute, faces usually ± piloso-hirsute (at least near margins, hairs 1-3+ mm), sometimes glabrate. Heads (1-)3-9+ in corymbiform arrays. Peduncles stellate-pubescent and stipitate-glandular. Calyculi: bractlets 13-16+. Involucres ± obconic, 8-10 mm. Phyllaries ca. 21+, apices acute to acuminate, abaxial faces stellate-pubescent and stipitate-glandular. Florets 40-80+; corollas yellow, 13-18 mm. Cypselae columnar, 2.5-3 mm; pappi of 30-40+, stramineous bristles in ± 2 series, ca. 5 mm. Flowering (Jun-)Jul-Aug. Disturbed sites, openings in thickets; 10-100+ m; Greenland; B.C., N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que.; Conn., Del., Maine, Mass., Mich., Minn., N.H., N.J., N.Y., Oreg., Pa., R.I., Vt., Wash., Wis.; Europe. The correct name for the species here called Hieracium vulgatum may be H. lachenallii C. C. Gmelin (E. Lepage 1971; E. G. Voss 1972-1996, vol. 3). Plants of H. groenlandicum (stems mostly piloso-hirsute and not stipitate-glandular, corolla lobes distally ciliate) are sometimes treated as distinct from H. vulgatum in a narrow sense (stems usually stipitate-glandular and not piloso-hirsute, corolla lobes not ciliate distally).
Plant with a short stout rhizome or caudex; stem 1.5-10 dm, sparsely setose and stellate to subglabrous; lvs long-hirsute, with narrowly to broadly elliptic or even lance-ovate blade 2-13 נ1.5-5.5 cm, tapering to the base, generally with at least a few sharp coarse teeth toward the base, mostly exceeding the petiole; cauline lvs 2-several, reduced and scattered upwards; infl open, corymbiform, the stout peduncles long-stipitate-glandular and ±stellate; invol 8-12 mm, hispid with blackish, gland-tipped hairs and often also stellate; fls 40-80; achenes 2.5-3.5 mm; 2n=27. Fields, roadsides, and other waste places; native to Europe, intr. from Nf. and Que. to N.J. and Minn. May-Aug. (H. maculatum, with spotted lvs; H. vulgatum)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.