Here we are at the end of October… Yellow maple leaves are falling steadily around me, with a little help from light rain. The forest floor is totally covered in leaf litter by now, making it hard to find fall mushrooms, even if they are out there. But—under the protection of hemlock trees in my backyard, there are patches of white mushrooms lurking in the dark shadow of hemlock boughs. I’ve been watching them for over a week now, and they’ve rewarded my curiosity with a fabulous little natural history display.
The first day I saw them, I noticed a scattering of small, white, button mushrooms, looking a lot like the grocery-store variety. Soon it became clear that they were part of an arc-shaped colony—almost a fairy ring of white mushrooms. In a few more days, they increased in height as their stems widened at the base and then lengthened. The rims of the pure white caps remained rolled under (or incurved) and the crowded gills stayed white. Even when the mushrooms did begin to flatten out, they never lost their impressive “white” wow-factor.
I took some photos of them and then pulled up a mushroom to thoroughly examine it. I noticed that it was attached to the leaf litter by way of a mat of mycelium (white roots attached to the substrate.) I scratched the gills and cap, but they didn’t discolor very much. I took the mushroom home and made a spore print—and guess what? The spores are white too!
Then I got to work trying to identify this mushroom. Although I never learned its common name, here’s what I’ve come up with from various sources:
Leucopaxillus albissimus is the name bestowed on this “whitest” of white mushrooms. (In Latin, the roots leuco- and albin- mean white.) Typically found under conifer trees in summer and fall, this mushroom makes its living as a saprobe by decomposing leaf litter. The cap is dry and smooth, white to buff in color, and the rim is incurved, especially when young. The gills are also white to buff, crowded, and attached to the stem. Mature specimens are 3-5 inches in height, with caps up to 6 inches across. It is considered inedible.
One more observation: After two weeks, this species seems uncannily resistant to aging or decomposing. According to Wikipedia, “Members of Leucopaxillus have antibiotics which make the mushrooms persist much longer than most.”
Wait–it can make antibiotics and therefore control its environment?! How cool is that?!
VIRGINIA WILDFLOWERS 
Wonderful find!
Great description and story! Well done!
Very cool! I loved your description of them growing in a “fairy arc.”