32. Hieracium venosum Linnaeus, Sp. Pl. 2: 800. 1753.
Hieracium venosum var. nudicaule (Michaux) Farwell
Plants ca. 45 cm. Stems proximally piloso-hirsute (hairs 1–3+ mm) to glabrate, distally usually glabrous, rarely piloso-hirsute. Leaves: basal 3–6+, cauline 0–1+; blades obovate or elliptic to oblanceolate, 40–60(–120) × 15–35(–50+) mm, lengths 2–3(–4) times widths, bases cuneate, margins usually entire, sometimes denticulate, apices rounded to acute, abaxial faces piloso-hirsute (hairs 2–5 mm) and stellate-pubescent, adaxial glabrous or piloso-hirsute (mostly near margins, hairs 2–3 mm). Heads 4–10(–20+) in corymbiform to paniculiform arrays. Peduncles usually stipitate-glandular, rarely glabrous or glabrate. Calyculi: bractlets 6–10+. Involucres obconic to campanulate, 7–9 mm. Phyllaries 12–13+, apices acute, abaxial faces usually stellate-pubescent and stipitate-glandular, rarely glabrous. Florets 30–45+; corollas yellow (sometimes pale), 7–11 mm. Cypselae (usually black, sometimes red-brown) columnar, 3–4 mm; pappi of ca. 50+, stramineous bristles in ± 2 series, 4–5 mm.
Flowering (Apr–)May–Jul(–Sep). Openings in forests, sandy hillsides; 10–300 m; Ont.; Ala., Conn., Del., D.C., Ga., Ill., Ind., Ky., Maine, Md., Mass., Mich., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Vt., Va., W.Va.
Plants of Hieracium venosum with adaxial faces of leaf blades glabrous have been called var. nudicaule.
The type of Hieracium marianum Willdenow may have resulted from a cross between plants of H. venosum and H. gronovii or H. scabrum (M. L. Fernald 1943c).