St. John's Wort

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The National Institute of Health reports that scientific research on the plant's medicinal value is limited. Research is onging and inconclusive. Please read the literature.
The plant grows wild on roadsides and distrubed areas across the United States. The yellow flowers bloom throughout the summer.
In areas where the plant becomes invasive, beetles called Chrysolina quadrigemina have been used as an effective biological control agents.
© 2008 Patricia A. Michaels
