St. Johnswort


(This column was first published in the July 15, 2002 Buffalo News.)


There is surely no wildflower that enjoys a better press than St. Johnswort. It seems that every few weeks another newspaper article appears and I just finished reading one of the seven books our regional libraries carry about this unprepossessing but widespread little plant.


Before we explore the source of all the attention, I'll introduce you to these weeds.


Notice the plural there. My Peterson and McKenny wildflower guide carries a full page of St. Johnsworts with eight species listed. What they all share are opposite leaves and many bright yellow blossoms with five petals, the center of each of those blossoms filled with an array of bushy stamens.


The most widespread of the eight is the appropriately named common St. Johnswort, also called Klamath weed or goatweed. The only introduced species in the group, it contributes its bright yellow to our roadsides and untended fields. What distinguishes this species from its cousins is the line of black dots along the edge of each petal.


These are all midsummer plants, first blossoming at the time of the late-June summer solstice and continuing to bloom until September. Their common name derives from the celebration in midsummer of the birth of John the Baptist. And their genus, Hypericum, comes to us from a still older belief system. This name relates to Hyperion, the father of the Greek sun god, Helios, so that it is again appropriate to the time of our longest days.


Why then all the fuss and bother about this admittedly attractive plant that so often fills in and improves the appearance of our waste areas?


The answer to that question may be seen in the subtitle of the book I read: Norman Rosenthal's St. John's Wort: The Herbal Way to Feeling Good. Medicine derived from the plant is widely used as an antidepressant, a "natural" alternative to many widely-prescribed drugs. Its use is far from insignificant. The market for St. Johnswort is over a half billion dollars worldwide. In Germany, for example, it is recommended by doctors four times as often as Prozac. It is now being touted by some as a weight loss aid which will still further increase its sales.


Although its use is increasing exponentially today, this herb has a 2400-year history and is even said to have been prescribed by Hippocrates, the father of modern medicine.


I found Dr. Rosenthal's presentation quite reasonable. He clearly believes in this herbal remedy and provides much anecdotal evidence in its favor. However, he is careful to warn those who wish to use it to seek the counsel of a physician.


The problem with this herb as with virtually all other natural dietary supplements is that, despite all the anecdotal evidence and unlike standard pharmaceuticals, it has not met the strict standards of medical testing. Such testing involves comparison of the tested intervention with a disguised non-effective pill called a placebo. The two are administered to different groups in such a way that neither the users nor the persons giving the pills know which is being taken. This is called a double-blind experiment.


In fact the National Center for Complementary and Alternative Medicine recently completed the first such test, finding the herb "ineffective for major depression of moderate severity."


Doctors warn of negative interactions of St. Johnswort with other drugs and there are photosensitivity issues: animal symptoms include skin blisters and hair loss. Also a Los Angeles Times study found that the quality of over-the-counter pills fell far short of advertised claims.


Despite these problems, this herb may still be right for you. Caution is advised, however.-- Gerry Rising

Added Notes: During the first half of the 20th century especially in the drier lands of western North America, St. Johnswort was a very serious pest weed, infesting at one time over 2 million acres of grazing lands, where it choked out the grasses on which the cattle fed and infected horses and sheep with scabbed noses, until in 1951 an European beetle was brought in to control it.

This same plant created great difficulties for Gregor Mendel, the great geneticist. Mendel was asked by one of the "authorities" to whom he sent his findings, to replicate what he had discovered with St. Johnswort. He had no luck whatsoever because, unlike the peas that Mendel had been using, St. Johnswort does not breed true.-- Gerry Rising