White bog orchid peaks in bloom across glacial fens
July 21, 2026
(Platanthera dilatata leucostachyus) is in peak bloom this week in the calcareous fens near East Calais, with three observations recorded between July 4–8. This threatened orchid flowers in a narrow 2–3 week window each summer, and finding it in full bloom is a sign that something essential underground remains intact.These orchids grow only where cold groundwater seeps year-round through calcium-rich glacial till, keeping root zones chilled through the warmest months. Any disruption of that cold-water plumbing—warming, drainage, or altered flow—and the plants vanish. Calcareous fens themselves are relicts of the glacial landscape, now covering less than a fraction of a percent of Vermont's wetland area. Two centuries of agricultural and residential drainage have reduced and fragmented what little remains. For now, the geologic infrastructure that sustains these orchids—the post-glacial heritage buried beneath the fen—is still working. But it is fragile, and it will not recover if lost.
