A Giant's Playground

We've spent a lot of time in our woods at the snowmobile trail this fall.  One of the fascinating things about this section of the woods is the number of really large boulders that are scattered  throughout the woods.  It  looks like some clumsy giant just dropped a bunch of rocks that he had been collecting in order to pick up something else.  And, the rocks aren't really uniform. There are different colors and patterns to the rocks; even two that are right next to each other appear to be completely different.  This got us curious: what caused this?  Did the water wash the soil away leaving these rocks in place?  Or, did they come from somewhere else.  The answer came from a book that we purchased in a bookstore in Lake Placid a couple of years ago called "Why the Adirondacks Look the Way They Do" by Mike Storey.  In it, Storey describes the glacial activity that swept over our region of NYS during the last glacial period. The ice swept down from Canada (not actually called Canada then, since it was about 600,000 years ago) and became lodged on the Adirondack mountains.  Because it was stuck there due to the "pointy-ness" of the mountains, when the ice began to melt, these giant sheets of ice didn't retreat the way they did in other regions but instead stayed in place and melted from the top down.  This melting meant that the many boulders that were trapped in the bottom section of the ice (which was a staggering 2 miles thick at times) were left behind when the glaciers finally disappeared.  These rocks are technically known as "glacial erratics," and the soil that our woods sits on is known as "glacial till."  It is a  mix of various soil types including silt, clay, cobbles, and boulders, and is relatively rich in nutrients.  The other clue that we're sitting on glacial till is the presence of sugar maples- this section of our woods is rich in these "hard maples" compared to other sections. 

If you're interested in the geologic history of the Adirondacks, we'd recommend Storey's book.  It's fascinating reading, and we enjoyed learning a bit about what we see around us every time we head for the woods.