This aquatic perennial can grow to be about 30" tall and just as wide. It grows best in full sun and wet soils or standing water. White flowers emerge in a whorls of 3's along the long flower spike from July to October. It's large 10" arrowhead shaped are a host to the yellow and black caterpillar of the Smear Dagger Moth.
 
Found mostly in the Piedmont, and sparse along the Coast.
 
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