This section is from the book "Who's Who Among The Wild Flowers", by W. I. Beecroft. Also available from Amazon: A Field Guide to Edible Wild Plants.
Hypericum perforatum. St. John's-wort Family. June - Sept.
A plant 1 - 2 feet high, found in fields, roadsides. Common throughout the United States. Naturalized from Europe.
Yellow, in clusters terminating the branches; divisions 5, black-dotted along the margins.
Small, opposite, oblong, more or less black-dotted.

Common St. John's-wort.
 
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