Smooth Aster, Symphyotrichum laeve
(formerly Aster laevis  what happened?)
Asteraceae or Sunflower Family

Medium plant, 1 to 4 feet tall. Stems smooth, with whitish bloom. Leaves long and narrow, thick and smooth to the touch, mostly untoothed or with small teeth. Flowerheads medium-sized, 3/4 to 1 inch wide, with blue to violet rays and yellow discs, turning purple. Blooms in autumn.

Beautiful native of dry fields and open woods. Occasional in the Park in partly sunny areas.

New England aster (S. novae-angliae) has even larger flowers, and may no longer exist in the Park. New York aster (S. novi-belgii) has very narrow leaves. Other asters in the Park have white or pale flowers or heart-shaped leaves..