This year saw me change assignments at work. The actual location was about 16 miles of road distance from where I’d been, but the “as the crow flies” distance was only around 6 miles. What was interesting to observe was the changes in the mix of species I saw. You see, I crossed a divide.
Here’s where I used to work:
Pretty, right? The water you see in the foreground flows into the Hudson River. On the other side of that ridge? It all flows into the St Lawrence River. This is on the way to the St Lawrence:
In the macro sense, there isn’t a lot of difference. You see the same animals, the same tree mix, the lakes have mostly the same kinds of fish, and the same kinds of biting insects. So even though you’re on the other side of a divide, and there really isn’t a big distance, there wouldn’t be any other changes. Which turned out to be not quite true.
On the Hudson side, the most common undergrowth brush was this plant:
It’s locally known as “hobblebush.” It’s scientific name is Viburnum lantanoides. The reason it’s known as “hobblebush” is it’s habit of putting new roots out of its stem, and forming a rather impenetrable tangle. On the St. Lawrence side? This plant:
It’s Gray Dogwood, or Cornus racemosa. Like the hobblebush, it also roots out of stems, and forms impenetrable tangles. Both are found on either side of the divide, but they switch places. You can find a small patch of rather scraggly looking plants of one, while the other is all over the place.
Another difference I saw was the dragonflies. On the Hudson side, the predominate dragonflies were skimmers (chalk-fronted corporals) or darners. On the St. Lawrence side? The skimmers weren’t very common, an occasional darner, but a lot of clubtails and baskettails.
Why the difference? I don’t know. That’s the fun part. There doesn’t seem that there should be a difference, except where the water ends up. They’re much the same geology, same soil types, same trees, and the same verterbrates. There’s not a lot of distance between them, and the ridge isn’t all that high. Yet, for some reason, there are changes. I may never know why, but it just goes to show that you can always be surprised.