Several miles before we reached the overgrown parking area, what with its lush blackberry canes and rangy patches of sumac, we pulled over on the rugged Forest Service road to look at the adjacent woods. My colleagues spoke fondly of these woods, having burned them at least once in some 10 years. Usual dry chert woodland suspects were present here in small, diminished numbers, poking through the accumulated leaf litter: desmodiums, dittany, lespedezas (the native ones only), some sunflowers, a handful of native grasses. We stomped along the woodland edge, knowing that what we saw here would dramatically pale in comparison to what awaited us just past the parking area. But rather than waste our time looking at beat up woods, we found ourselves gathering nice big hunks of chert from the roadbed to take home with us. Yes, I realized then, I was in the right company.
After hauling not one, not two, but six enormous blocks of chert into the back of the fancy unblemished SUV, we finally made our way to our destination: Grasshopper Hollow, owned, thankfully, by the Nature Conservancy and not a state or federal agency. I'd heard about Grasshopper Hollow for several years now: it's the "best remaining example of a prairie fen in Missouri," and that it is, unsurpassed, the "largest unglaciated fen complex in North America." And it's in Reynolds Co., the heart of Missouri's Ozark Highlands. My colleague had told me repeatedly that I needed to see it for myself, what with my recent affinity for fen complexes and perennial admiration for prairie plants. But having traversed a veritable maze of Forest Service roads that morning, I realized that I never would have found Grasshopper Hollow for myself, despite decent map reading skills, so it was a definite boon that my colleague took us there himself.
When we finally arrived at the parking area, we gorged on blackberries, each of us eating several handfuls. We commented, as usual, on the lousy state of the woodland edge: exotic spotted knapweed moving into the woods, exotic sericea in the manmade ditches. We've all seen plenty of these non-native plants this growing season, but none of us had seen a pristine prairie fen, managed with fire and so rich with grasses and wildflowers that it was hard to even step for fear of damaging something.
We followed an old logging road to reach the fen, passing a lousy manmade lake and ditch system installed sometime in the past century to deal with the excess groundwater seeping from the fen. But just past the woodland edge was a landscape so incredibly diverse that it rendered me almost speechless; all I could muster was a barely audible "oh, my God." I learned my fen plants from books this past winter, wanting to know the plants upon seeing them in the field so I wouldn't have to rustle through field guides (which seldom -if ever- include fen plants anyway). I learned my sedges, orchids, lilies. Despite the incredible floral display I had seen earlier in the season in Ozark fens of the Niangua Basin and St. Francois Knobs and Basins, I simply wasn't emotionally prepared for the biodiversity of Grasshopper Hollow.
It dawned on me last month when my pictures of the prairie fen were met with a "huh, looks like a grassy field..." that perhaps the incredible richness of high quality prairie fens should be better explained before the pictures are dismissed as old fields. Because few people in this world can write as succinctly as Paul Nelson, I'll borrow his description of the prairie fen from his Terrestrial Natural Communities of Missouri:
Prairie fens are not as boglike as typical fens. Prairie fens occur on toeslopes along valley terraces or floodplains of larger streams....Soils are somewhat poorly drained to poorly drained and shallow to very deep with a neutral or moderately alkaline soil reaction. Soil fertility is naturally moderate to high. Calcareous groundwater supplies seasonal saturation. Little or no external flow is visible although localized areas of constant internal seepage occur....
Unlike in (formerly classified) deep muck fens, we could walk comfortably through the prairie fen that day, but it took deliberation. Imagine prairie grasses so thick and impenetrable that movement through the fen took a conscious effort, a slow placement of one foot in front of the other between enormous clumps of big bluestem. None of us wanted to forge even a temporary path through the pristine fen, but to walk through it, we had to step on plants. We continued to walk slowly, feeling with our feet patches of bare earth--rare patches at Grasshopper Hollow.
Among the tall prairie grasses were intermingled populations of Culver's root and Michigan lily (both pictured above), providing great splashes of white and brilliant orange to the prairie. We were there too early for the bloom period of prairie dock, but flower stalks 8 feet tall towered above, gearing up for a July bloom. Rare to Missouri wood frogs live here, along with four-toed salamanders and the federally endangered fen obligate, Hine's emerald dragonfly. A host of sedges and wildflowers native to fens thrive here in healthy populations. After we had been on the prairie fen an hour or so, a raging thunderstorm rumbled in, spilling water all over the deep soils of Grasshopper Hollow. I expected the peaty soils to hold water above ground, to turn our walk through the dry prairie fen into a mucky mess. Rather, the rainwater was quickly absorbed by the thick black soils, nourishing the root systems of grasses which reach on average 12 feet into the earth.
Grasshopper Hollow actually contains 15 separate fens representing various Ozark fen types. As the storms moved in, we rushed through the tall grass of the prairie fen into woods recently burned, judging by their wonderful open character and rich ground cover. Roughly 500 yards through the woods, my colleague pressed on ever quickly through an alder thicket so dense and thick we thought we had lost him to it. The rest of the party plowed through, breaking branches and stepping on decomposing logs to avoid soaking their boots in the wet, peaty soils. I lacked the brute force, the strength, to tear through the alders quickly. Leafy branches slapped me in the face, my hair tangled in lower limbs. I grew a little cranky about the alder thicket until I finally saw my colleagues ahead, resting on a log. (It's tough spending time in well managed, open woods and prairies and then stepping into a dense, dark, impenetrable thicket. It's no fun, really, and it makes me tense.) I think they could tell by my expression that I wanted an explanation for the alder thicket and the necessary bushwhacking it required. Why, in a beautifully managed acreage, is it there?
Apparently, Grasshopper Hollow, like many other fen complexes in Missouri, was once home to a thriving beaver population. As the beavers laid waste to the canopy above what may have been a forested fen, alders moved in, perhaps diminishing the fen ground flora. But next to the alders in full sun was a thick groundcover of pinnate prairie coneflower and prairie dock, whose large leaves measured greater than any I'd ever seen on a prairie. The prairie fen, it seemed, continued past the alder thicket. My colleague stands there waiting for me to traverse the prairie dock, looking largely diminished against the strapping waist high leaves.
We waited out the summer storm on the midslope of the woods, watching as lightning crashed to our south. Drenched, soaked to the core, we made our way back to the prairie fen to see the mist rise above the grasses and, again, the vast expanse of fen. Rare are the places in Missouri where exotic species don't have a foothold and prove a challenge to manage. Grasshopper Hollow is one of those places. Of all the literally hundreds of plant species we saw that day, not a one was exotic. No crown vetch, fescue, or even clover could find a spot to thrive in a place so well managed. While I don't know for certain, I imagine the plant list for the complex contains over 300 species. An old field, on the other hand, weighs in under 100 on a good day.