Bottle (or Closed) Gentians, Gentiana andrewsii, are among the last of the tallgrass wildflowers to bloom before hard frosts and late autumn arrive --- and those we found Sunday on the prairie remnant east of Derby were past their prime. But at Pin Oak Marsh early this week, they were at their peak.
The Bottles prefer moist black soil, so the marsh is an ideal setting. Some speculate that destruction of Midwest wetlands is resulting in a population decline, but Lucas County has enjoyed a marsh renaissance for several years now --- so that should not be an issue here.
The name "Bottle" results from the fact blossoms never fully open. As a result, bumblebees are primary pollinators. Those big bullies are powerful enough to force their way in.
At least two Bottle Gentian colonies are located conveniently near trails at Pin Oak --- in case you want to take a look yourself.
The first is on the west side of the paved trail a few paces beyond the first bench. You'll have to look carefully here, however, because our moist summer has resulted in extremely tall grasses and the gentians are only a foot or two tall. I missed them walking southeast, but spotted them easily on the return trip.
A bigger and stronger colony is located alongside the grass trail that leads south from the paved trail to the berm that defines the south shore of the big marsh pond. The gentians grow right along the trail, and some distance west of it, perhaps four-fifths of the way to the berm.