Calcareous fens

On July 17, I visited several calcareous fens in northwestern Minnesota. These fens lie within the prairie or on the edge of it. The calcium present in these areas gives the soil a near-neutral pH. The seepage probably prevents the soil from freezing hard. The mineral soil is overlaid by muck that is rather vacuous. Occasionally, someone would step in a spot where the mat of plant roots was weak and they would drop through into the muck past their knee. Sometimes, they'd have trouble pulling their foot out and need to get rescued. These plant communities are unique, including potentilla (Potentilla fruticosa, whose yellow flowers were beginning to open), sterile sedge, and various small orchids. I think they are the only type of plant community that is protected by state statute. One fen contained scattered tamaracks (Larix laricina) of various sizes, but mostly small. They seemed to be growing well, and could lead a forester to think that timber production was a viable use for that site. Whether they would ever produce a merchantable volume of timber is debatable, but extracting it would likely be impossible due to the wetness of the site. The fens are botanically interesting, but not overwhelmingly attractive landscape features.

We saw wood lilies (Lilium philadelphicum) and wild licorice (Glycyrrhiza lepidota) blooming in nearby meadows. In prairie areas, lead plant (Amorpha canescens), joe pye weed (Eupatorium maculatum), and various milkweeds (Asclepias spp.) and prairie clovers (Dalea spp.) were blooming. Some of these plants, although common in the prairie, were, by far, more outstandingly beautiful than those we saw in the fens. The wood lily was especially pretty.