Fall Wildflowers - Great Blue Lobelia (Lobelia siphilitica)

Great Blue Lobelia is a native perennial blooming in late summer/ early fall in the eastern US. Its large showy flowers make it easy to spot and identify. Each flower is split into two 'lips' - the upper has two segments and the lower has three. 
This flower is the blue counterpart of the Cardinal Flower (bright red blooming about the same time).
All parts of this plant are toxic, even though it once was supposed as a cure for syphilis (as reflected in its species name).

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