This section is from the book "Harper's Guide To Wild Flowers", by Caroline A. Creevey. Also available from Amazon: Harper's Guide To Wild Flowers.
P. cristatum is a more slender, twining species, 12 to 20 inches long. Leaves, triangular, with rather sharp basal angles and pointed apex, long-petioled. Flowers, generally in leafless racemes on jointed pedicels, greenish.
In sandy woods and rocky banks from southern New York to Georgia, westward to Tennessee and Texas.
 
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