St. John's Wort, a medicinal invader.

By Johnny Caryopsis.

Hmm, it is St. John's Wort. I had been wondering about the patch of yellow flowers along the road near my cottage for some time. I'm actually pretty good at identifying plants in the roadsides while driving along. And no, I don't rubber-neck and risk causing a crash, I just have a lot of experience at high-speed plant identification. One quick glance is usually all it takes.

(The roadside view that had intrigued me: Click for pic.)

But this patch didn't register in the plant recognition database (PRD) within my grey matter. So, after passing this patch a few times and thinking after each pass that I should have remembered to bring my camera and make a stop, I finally did remember prior to heading out one day. I purposely packed my camera and on the way back from the grocery store I actually did stop.

As soon as I got close I recognized the plant as St. John's Wort (Hypericum perforatum). The reason, I told myself, that this species hadn't popped up on the PRD was that it was an alien invader. Typically, I'm so focused on Manitoba's native plants that I tend to disregard non-natives. Later on, of course, I admitted to myself that I really didn't know this particular plant all that well. I just hadn't seen it enough times for it to be loaded in the highway-speed section of the PRD. It was time to make a thorough entry in the PRD for this species. I just don't like not knowing what stuff is.

Turns out, my ignorance of this plant was quite extensive. I knew it was an exotic species and that it had some herbal qualities, and that it had bright yellow flowers, but that was about it. So, being at the lake and having lots of time on my hands, and access to the internet, albeit dial-up speed, I indulged in my craving for eliminating "not knowing" about St. John's Wort. Here's what I found out.

Click the right arrow below for more.


Carry on for the Biology of St. John's Wort

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