This species was first collected in Montgomery County by A. R. Bechtel. It was common on a wooded bank of Sugar Creek about 3 miles north of Crawfordsville in 1926, and in 1927 it was collected in Jonathan Winters' woods about 2 miles northwest of Darlington. In 1935 it was discovered by Miss Edna Banta to be a frequent to common weed along the road and adjacent areas along the river bluff between Brooksburg and Madison in Jefferson County.
Much like no. 1 [Torilis arvensis (Huds.) Link]; lvs often a little less dissected; invol of several bracts, commonly 1 to each ray; fr with shorter, stouter, more obviously subconic, less widely spreading, more upcurved prickles ca 0.5 mm or a little less; 2n=16. Native to the Old World, now widely established as a weed in our range, but less common than no. 1. (T. anthriscus, a preoccupied name)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.