Petasites frigidus (L.) Fr.

  • Authority

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

  • Family


  • Scientific Name

    Petasites frigidus (L.) Fr.

  • Description

    Species Description - Rhizomatous perennial; basal lvs long- petioled, glabrous or sparsely hirsute above, loosely white-tomentulose beneath, large, 5–40 cm wide, palmately or pinnipalmately veined and lobed and also ± toothed; stem 1–5 dm, with parallel-veined bracts 2.5–6 cm, the lower sometimes with an abortive blade at the end; heads campanulate in a corymbiform or racemiform infl; invol 5–9 mm; fls whitish, the outer 10–25 in pistillate heads with short rays 2–7 mm; 2n=60(–62). Meadows, swampy places, and moist woods; circumboreal, s. in Amer. to Mass., Mich., Minn., and Calif. Apr.–July. Nearly all our plants belong to var. palmatus (Aiton) Cronquist, with the lvs palmately cleft well over half way to the base. (P. palmatus) A few plants from n. Minn. and n. Mich. (and northward) with the lvs palmately or pinnipalmately cleft not more than about half way to the base, may reflect hybridization with no. 2 [Petasites sagittatus (Banks) A. Gray]. The name P. ×vitifolius Greene is available for these.

  • Common Names

    northern sweet-coltsfoot