Some of the stately oak and hickory trees that made up the original Big Grove still stand, their craggy trunks rising solidly out of the snow covered park. But my eyes and lens continually focused on a tree I'd never seen before. It lined the banks of the lake and river that feeds it, its branches heavily drooped with the most unique combination of fruiting bodies.
The branches of the tree were decorated with what appeared to be both long, thin catkins and short, plump cones.
The bark of the trees was a fissured, fractured pattern circling around branch knots.
When I returned home, I immediately grabbed my Sibley Guide to Trees. A quick flip through the pages and the familiar look of the longer catkins led me to hone in on the birch family. That's where I found the section on alders -- a subset of birches -- where Sibley notes that alders are known for the ability to fix nitrogen from the air, fertilizing and stabilizing barren areas and riverbanks.
Several species of alder have the characteristic long, narrow (male) catkins and corresponding short, plump (female) catkins. As a best guess, I'd say the alders outlining Crystal Lake are European or Black Alder (Alnus glutinosa), based primarily on the craggy bark and area of distribution.
I plan to return to the park in the spring and summer to examine and photograph the alders along the water, talk to the Busey Woods naturalists to confirm the species. But whatever their botanical name, I know one thing for certain. Alder is one of the more unusual trees I have run across, and look forward to learning more about these catkins of a different kind.