To 15 dm, branched above, glabrous and ±glaucous throughout; lvs ovate in outline, the lower long-petioled, the upper less so and smaller; ultimate lf-segments 5-20 mm; umbels to 15 cm wide; rays mostly 30-40, spreading, subequal; fr 3-5 mm, half as wide; 2n=22. Native of s. Europe, escaped from cult. throughout most of the U.S. and elsewhere. July, Aug.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.