calico aster, Symphyotrichum lateriflorum

Notice the differing colors of the central florets. The disc flowers of most if not all asters change from yellow to purple as they age. Could this be the reason for calico's name? Or could it be the relatively small heads arranged on short stems along the branches? That tends to make them line up in rows. In any case, they're a nice sight in late season woods in AL, AR, CT, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, NC, NE, NH, NJ, NY, OH, OK, PA, RI, SC, SD, TN, TX, VA, VT, WI, WV, BC, MB, NB, NS, ON, PE, and QC. Ives Preserve, Lenawee Co MI, 9/17/11. Aster family, Asteraceae.