The wetland above really caught my eye. It is a mile or so on west of stork swamp, and is dominated by Softstem Bulrush, Schoenoplectus tabernaemontani. The first chance I got, back I went. And found a great plant, but the day was not optimal for photography or exploring, and time constraints had me raring for a repeat visit. Which was yesterday. This wetland is a rather soupy quagmire, the ground soft and spongy and in places it is like stepping into oatmeal that threatens to suck you in. But it is well worth it.
This is the main attraction, at least for the botanist. Walter's St. John's-wort, Triadenum walteri, a beautiful and robust member of the pink-flowered marsh St. John's-wort complex. Sherri and I counted a lot - maybe 300 to 400 plants reside in the wetland. They have passed out of flower and into fruit, but are still good-looking plants, and their presence is all the more noteworthy because of their rarity. There are two or three extant populations in Ohio of this endangered species.
A closeup of the mature fruit. The tiny modified leaves that cup the fruit are called sepals, and are one of the differentiating characters among the Triadenum St. John's-worts. In this case, they are oblong with a nice rounded summit. The leaves are dotted below with tiny translucent dots, and are held on distinct petioles, or short stalks. All of these features serve to separate from other more common members of its ilk.
Incredibly, we found another, almost as rare St. John's-wort in the same wetland. This one, shown above in a photo from the voucher specimen that I took, is Triadenum tubulosum, the Large Marsh St. John's-wort. This one is threatened in Ohio, which means it is known from five or fewer sites. A close look at the sepals around the fruit reveals that they are sharp and pointed, very different than those of T. walteri and its short rounded sepals. This one also has leaves that closely clasp the stem, which can be seen in this photo, and an important feature for its identification is a character that is not present. Unlike the others, this one has no translucent or punctate dotting on the underside of the leaves.
There is an old, unwritten rule for finding rare plants. Take the Path of Greatest Resistance. Seek the hardest ways to explore habitats. We found this one by entering a boring looking young woodland dominated by Silver Maple, and choked with floodborn detritus. And Bingo - there was Large Marsh St. John's-wort. Plants like these two species probably are genuinely rare in Ohio, as both are at the extreme northern limits of their range in Ohio. Still, they are likely overlooked to some degree, as people are often apprehensive about entering their soupy haunts.
In this particular case of discovery, I thank the Wood Storks for bringing me over to this area in the first place.
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