Mystery Plant: Alligator weed”, Alternanthera philoxeroides

I am thinking that some of you might have been inclined in the past, and even now, to spend time around a pond or lake, perhaps a large impoundment such as our own Lake Murray here in central South Carolina. Perhaps you’ve been in a kayak, paddling around, or a pontoon boat, enjoying a late-afternoon cold refreshment. Or maybe you were fishing somewhere along one of those lakes, or maybe even swimming at a boat landing, enjoying what cool there was. I am further thinking that if you have spent much time around the edges of such waterways you may have seen this plant.

This plant was (and still is, of course), native to central South America. The first botanist ever to pay any attention to it, that is, by discussing its name, was a German gentleman named Carl Friedrich Philipp von Martius. (Can you imagine what it was like in the first grade having to write such a name at the top of your arithmetic quiz? Botanists, when referring to him in a publication these days, just write “Martius.”) Well, it turns out that the King of Bavaria gave him a pretty interesting job, which was to go to Brazil in order to discover and describe new plants. Martius was quite up to this task and came up with a lot of names for plants new to science. Our Mystery Plant is one of them: it was described in 1825. Martius must have first seen this plant in a quiet backwater or bayou somewhere down there near the Amazon.