Tuesday, June 23, 2009

Lakes, Bogs and Beavers

The yellow lady slippers mentioned in my earlier blog are in full bloom, so I took pictures. Converted the above to a sketch format. I usually don’t like the result, but this one is interesting.
Some blueberry plants nearby are blossoming and look healthy. Cranberries there aren’t doing as well. They seem susceptible to frost when they aren’t covered by water in early spring. The plants have spread out quite a bit since I bought them three years ago, but only a few of the runners survived this spring’s late frost. The wild cranberries I’m familiar with at a nearby lake are covered by water in early spring. The water level doesn’t drop until about the time they blossom. Beaver dams establish the lake level where the wild cranberries grow. I guess you could call it a “beaver enhanced” lake. It’s full to the top of the dams during the big spring thaw, but after that, the level drops. The wild cranberries grow on rotting logs that wick up moisture for the berries even after the water drops out of sight. Lake level comes down a foot or two in hot dry weather, but the shallow lake never gets clogged with weeds, thanks to the beavers. I used to assume that beavers ate only the bark of trees they are famous for cutting down, (infamous, if they get into your yard of orchard), but I’ve found that they eat mostly pond vegetation in the summer. Their favorite seems to be the yellow pond lily that’s called spatterdock (see picture in my earlier blog), but they like cattail roots and keep the shoreline cattails in check, too. I’ve also watched beaver families dive for hours to harvest deep-water weeds. Cedar trees need a foot or two of soil above the water table to survive, but there are a lot of old dead cedars offshore in a foot or two of water there. The trees probably grew there when the beaver population couldn’t keep up with dam repair – they may even have been trapped out for some period of time. When they came back and fixed the dams, the trees got flooded and died. That’s my guess, anyway.
Beavers have been around for centuries in most places. While hiking through a forest in the Appalachian Mountains of Pennsylvania, I found an ancient beaver dam nearly thirty feet tall, but the beavers were long gone. The impoundment was solid sediment, with trees in it the same age as the rest of the forest. Apparently, the beavers had kept building the dam higher to keep ahead of the sediment, until they finally gave up. They have their own environmental problems, I guess. There were many smaller abandoned dams farther upstream. I finally found an active dam way up at the top of the mountain, in a flat swampy area at the watershed divide. I’ve taken a lot of beaver pictures, but didn’t have my camera handy when I watched a baby beaver take a ride on his mother’s tail. I was trout fishing a dammed-up stream in thick woods. There was a cloud of mosquitoes so thick that I was inhaling them regularly. The mom dived under when she saw me, and left the little one treading water for a moment or two, quite confused. Then he dove out of sight, too. You’ll have to visualize a little fur-ball baby riding at the base of the tail of the one here. It’s the best I can do. Tally

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