Excerpts from Jim Conrad's
from the July 24, 2005 Newsletter issued from the Sierra Nevada foothills
somewhat east of Placerville, California, USA
ST. JOHN'S WORT GALORE
Yet another organism I've brushed shoulders with all my life but here is abundant beyond all expectation is the St. John's Wort, famous as an herbal medicine for depression. At http://www.hypericum.com/ the plant's medicinal value is much praised and of course you can buy several forms of it there. These folks even offer a free online book you can read called "Hypericum & Depression," at http://www.hypericum.com/toc.htm.
In contrast, the Quack-Watch site at http://www.quackwatch.org/01QuackeryRelatedTopics/DSH/stjohn.html questions the science of studies touting the value of St. John's Wort for treating depression, plus it describes various ways the plant can actually interfere with other medical treatments. It concludes that "There is no published evidence that St. John's Wort is effective against severe depression, which, in any case, should receive professional help. For mild depression, psychotherapy directed at resolving the cause of the depression might be more prudent."
There are many species of St. John's Wort -- 350 worldwide. We have six in California, including HYPERICUM PERFORATUM, which is the species usually sold in herb stores for depression. This is a native of Europe but also a weed all across North America, sometimes called Klamathweed. You can see it at http://www.missouriplants.com/Yellowopp/Hypericum_perforatum_page.html.
The species growing so abundantly along our roads is the closely related HYPERICUM FORMOSUM var SCOULERI, a native of western North America. You can see it at http://www.timetotrack.com/jay/socal/stjohn.htm. On the web I read that, medicinally, this species can be used interchangeably with H. perforatum. H. formosum's fruits are 3-pointed at the top while H. perforatum's fruits are 1-pointed. The yellow petals of both species, however, are fringed with curious- looking black dots.