Cardinal Flower (Lobelia cardinalis) 2014-8-15 Bombay Hook NWR, DE
I haven't seen many Cardinal Flowers to judge, but this certainly was the healthiest and *tallest* specimen I've encountered.
http://www.illinoiswildflowers.info/wetland/plants/cardinal.htm
http://plants.usda.gov/core/profile?symbol=LOCA2