On the bird walk this morning [two of us got a walk in between showers, EM walked over to a large sunflower and asked me how tall it was. I estimated 12 1/2 foot tall.
‘giant’ Sunflower at Kent P.
It is either Giant Sunflower [Helianthus grosseserratus] or Sawtooth sunflower [Helianthus giganteus]. Both are native species.