Lobelia cardinalis
from the link ☼
The blossoms are delicate, gradually opening from bottom to top on two to four foot spikes. Five petals are united into a scarlet two-lipped corolla. The lower lip has three very prominent lobes; the upper lip has two small ones. Five stamens are joined forming a red tube around the style and are topped by bearded anthers which form a mustache-looking brush.
In late summer the brilliant scarlet of Cardinal Flower flashes from the marshes, stream banks and low woods. Called "America's favorite" and "spectacular", its extremely showy blossoms can be recognized at considerable distance. Few native plants have flowers of such intense color as this common herbaceous perennial.
Beautiful but deadly, this plant has been used as a medicine but is also very poisonous. It contains fourteen alkaloids similar to those in nicotine.