Lfls sessile or nearly so, ovate to obovate, ±silky beneath, bright green or somewhat yellowish-green, thin, often bulging on the upper side between the principal lateral veins, these diverging from the midrib at an angle of ca 45Ь the teeth sharp and rather divergent, the terminal tooth more than half as wide as the adjacent lateral ones and (equaling or) projecting beyond them; peduncles at anthesis usually shorter than the lvs, later surpassing them; pedicels unequal and commonly proliferous, the infl eventually racemiform or paniculiform; pet 5-7 mm; 2n=14. Europe and N. Amer. Apr.-June. The chiefly European var. vesca, with ovoid or subglobose fr and with the long hairs of the petioles and peduncles widely spreading or even retrorse, is widely intr. in our range, and thought to be native in se. Can. Var. americana Porter, native from Nf. to Man., s. to Va., Ind., and Neb., has slenderly ovoid or ellipsoid fr, and the long hairs of the petioles and peduncles are ascending or appressed.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.