Wavy-leaved Aster,  Symphyotrichum undulatum
(formerly Aster undulatus  what happened?)
Asteraceae or Sunflower Family

Flower heads, 3/4 to 1 inch wide, have many central yellow disc flowers and 8-15 pale violet to white ray flowers.  Larger leaves are heart-shaped with a winged stalk.  Wing is enlarged at the base and clasps the stem.  Blooms in late fall.

Native.  Found in dry open spaces.

There are many asters in the Park, and they are hard to tell apart; however, the clasping enlarged base of the leafstalk is distinctive in this species.  Lowry's aster (S. lowrieanum) also has winged leafstalks but the base is not enlarged and does not clasp the stem, and the flowers are smaller.  Heart-leaved aster (S. cordifolium) has heart-shaped leaves, but the stalks are narrow and have no wings and the leaves are toothed. Schreber's aster (Eurybia schreberi) also has toothed heart-shaped leaves, but the flowers are white and the leafstalks are not winged.

Leaf and leafstalk