Hieracium pilosella L.
Family: Asteraceae
[Hieracium pilosella var. niveum Müll. Arg.,  more...]
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Plants 10-25(-40+) cm. Stems proximally piloso-hirsute (hairs 1-3+ mm) and stellate-pubescent, distally piloso-hirsute (hairs 1-2 mm), stellate-pubescent, and stipitate-glandular. Leaves: basal (2-)5-10+, cauline 0(-3); blades elliptic to ± oblanceolate, 10-45(-75+) × 5-12(-18+) mm, lengths 2-4(-6+) times widths, bases cuneate, margins entire, apices acute, faces piloso-hirsute (hairs 2-7+ mm) and stellate-pubescent. Heads usually borne singly, rarely 2(-3). Peduncles piloso-hirsute and stellate-pubescent. Calyculi: bractlets 8-15+. Involucres hemispheric to obconic, 7.5-9 mm. Phyllaries 20-34+, apices acuminate, abaxial faces stellate-pubescent and stipitate-glandular, sometimes piloso-hirsute as well. Florets 60-120+; corollas yellow (often each with abaxial red stripe), 8-13+ mm. Cypselae columnar, 1.5-2 mm; pappi of 30+, white bristles in 1 series, 4-5 mm.

Flowering May-Aug. Disturbed sites (sandy or gravelly soils, fields, lawns, roadsides); introduced; 10-100+ m; St. Pierre and Miquelon; B.C., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., Que.; Conn., Del., Ga., Ky., Maine, Md., Mass., Mich., Minn., N.H., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., Tenn., Vt., Va., Wash., W.Va.; Europe.

Abundantly stoloniferous, and with a long, slender rhizome; stem 3-25(-40) cm, lfless or with a single generally much reduced lf, viscid-puberulent or subtomentose, sparsely or moderately spreading-hispid with gland-tipped, usually blackish hairs, often long-setose as well; basal lvs oblanceolate or a little broader, 2-13 נ0.6-2 cm, tawny-tomentose with stellate hairs beneath, at least when young, and with some long glandless setae as well, green and glabrous above except for the long setae; lvs of the stolons similar but smaller; heads solitary, or rarely 2-3 and long- pedunculate on some individuals; invol 7-11 mm, stellate, short-hispid with black, sometimes gland- tipped hairs, and occasionally long-setose as well; achenes 1.5-2 mm, truncate; 2n=18, 36, 45, 54, 63. A weed in pastures and fields; native of Europe, now widespread in our range. May-Sept.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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