A walk through the woods with a professor and a few other curious souls gave me the full story. Wood-Rill Scientific and Natural Area is a reserve near Orono, Minnesota, deeded to the state by the celebrated Dayton (department stores) family, who used to enjoy it as their backyard. The trees here have always been here, since they were seedlings, and before them were other trees that sprouted, lived, and died without an axe.
The professor told us about the damage the earthworms have done. Earthworms? The gentle, squishy creatures we learned about in school that make the soil fertile and moist? Not so. Earthworms are not native to North America, and in the eastern woods they wreak havoc, stripping the soil of nutrients. Their burrows are everywhere. Little mounds, sometimes clusters of mounds, worms underneath. Spread by fishermen and others who transport nightcrawlers for bait and other uses, this plague threatens even mature forests.
An hour or so into the walk, a crack of thunder split the sky. But light continued to stream in through the gold and orange leaves, and raindrops held until we departed for our cars. Fall colors, even in Minnesota, can be elusive - you'll see patches along the roadsides, but to catch an entire forest in a cathedral of color, you have to get a bit lucky. You need sunlight to see the full effect. Last year we found it at Lake Maria State Park; this year it was Wood-Rill. I wonder where I'll be next year when the color surrounds me.
