Lactuca biennis (Moench) Fernald

  • 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

    Lactuca biennis (Moench) Fernald

  • Description

    Species Description - Robust, leafy-stemmed annual or biennial, 6-20 dm, glabrous, or the lvs hairy on the main veins beneath; lvs pinnatifid or occasionally merely toothed, 10-40 × 4-20 cm, sometimes sagittate at the base; heads numerous in an elongate, rather narrow, paniculiform infl, often crowded, with 15-34(-55) bluish to white or occasionally yellow fls; invol 10-14 mm in fr; achenes 4-5.5 mm, thin-edged, prominently several-nerved on each face, tapering to a beakless or shortly stout-beaked tip; pappus light brown; 2n=34. Moist places; Nf. to B.C., s. to N.C. (chiefly in the mts.), Ill., Colo., and Calif. (L. spicata, misapplied) An apparent hybrid with no. 3 [Lactuca canadensis L.] has been called L. ×morssii Robinson.

  • Common Names

    tall blue lettuce