Mycena corticola is a very little brown mushroom that grows on the bark of mature trees. It's so small it's measurements can be taken with millimeters. I like to look for it on rainy, above freezing days once winter weather sets in. I assume it grows during other seasons, but I've never actually looked for it. For me, finding M. corticola is sort of an "off" season mushroom hunting ritual.
It's probably present most of the year., but unless there's rain, it'll be dried up to almost nothing. The fruiting bodies of M. corticola have the ability to dry out and subsequently revive when exposed to moisture. For something so small and delicate it's remarkably persistent. This ability to revive probably explains why they show up on rainy winter days; they just need a little water to get going again.
I've taken an interest in White Mulberry, Morusalba trees this fall. What interests me the most is how variable the leaves are; shapes that can remind me of hearts, mittens, Y-wing Fighters, or a fleur de lis amongst others. It's usually a weedy tree in Minnesota, but White Mulberry is a tree with a rich history. It's leaves sustain silkworms, which are caterpillars of the silk moth Bombyxmori, and whose cocoons provide the raw material to make silk. The tree was brought to the United States in an attempt to start a domestic silk industry, which never thrived. But the White Mulberry tree did thrive and can be found throughout the eastern U.S., sometimes planted, but more often than not sprouting up in a sunny spots wherever a bird or other animal has dropped a seed.
Below a series of captioned sketches about White Mulberries.