This taxon is distinguished by the presence of glands in the inflorescence. It occurs mostly in or near the lower Mississippi Valley (Cr, FNA 21). In Ky. it is a remnant of original grasslands, surviving mostly in roadsides; extensive populations are restricted to Fort Campbell in TRIG and adjacent Tenn. (Chester 1992). Typical var. laciniatum occurs mostly in the midwest and is unknown in Ky., though a coll. from CALL (US) does appear transitional. See also notes on potential hybrids with pinnatifidum under that species; the plant mapped here from GRAY may be a hybrid. S. laciniatum is distinguished from pinnatifidum (W) by its "stem relatively leafy, with 4-5 nodes or more, the stem leaves smaller than the basal, but not merely bracteal" (versus nearly naked, with only a few very reduced bracteal leaves); also leaves are deeply pinnatifid to bipinnatifid (versus shallowly to deeply pinnatifid); and flowering heads tend to be larger (FNA 21), with 25-45 phyllaries (versus 23-33), hispid to scabrous on lower surface (versus glabrous) and often reflexed (versus all appressed), with ray florets 27-38 (versus 17-29) and disc florets 100-275 (versus 120-140); seeds (cypselae) are 10-18 x 6-12 mm (versus 7-13 x 4-10 mm), with pappi 1-3 mm (versus 0-1 mm).