Crooked-stemmed Aster,  Symphyotrichum prenanthoides
(formerly Aster prenanthoides  what happened?)
Asteraceae or Sunflower Family

Plant 1-3 feet tall.  Flowerheads with a yellow cluster of disc flowers and many narrow blue-violet ray flowers.  Entire head 1 to 1.5 inches across.  Leaves weakly toothed towards tip; lower third toothless.  Leaves abruptly narrow near base and then flare out again to clasp stem.  Stem zigazgs from leaf to leaf.  Blooms in the fall.

Native species of moist places.  Occasional in Wildwood in damp open places on the slopes.

There are many asters in the Park and they are difficult to tell apart.  The odd leaf shape makes this one fairly distinctive.  The similar purple-stemmed aster (Symphyotrichum puniceum) is taller, has red stems and leaves that narrow to a clasping base, and likes wetter spots.