Thursday, September 17, 2009
Black Mountain - Unique Granite Dome in Southern Vermont
The other day I walked up Black Mountain, one of my favorite haunts for as long as I have been living on Black Mountain Rd. The landscape of round granite boulders, scrub oak and pitch pine reminds me of my travels in the Sierra Nevada. Tom Wessels uses Black Mountain as an example of bald granite domes in the introductory chapter to his book The Granite Landscape . It's an outpost, the only granite dome in the southern part of Vermont. Much of the land is protected by The Nature Conservancy.
The mountain is in the shape of an horseshoe with the opening facing south; only one side is readily accessible in an easy 20 min walk from Black Mountain Rd. Copying and pasting the coordinates +42° 55' 0.57", -72° 35' 29.23" into Google Maps and clicking on Terrain gives a good picture of the shape of the mountain. The trail cuts through old stone walls, indicating that much of this, even high up, used to be pasture (see note below) which was eventually abandoned for the richer soil of the Midwest after opening of the Erie Canal in the first quarter of 19th century. The view from the top is toward Brattleboro and the Connecticut River Valley with the West River valley on the right and Mt. Monadnock on the left.
Tom Wessels calls the top of this mountain "the harshest, hottest and driest site in all Vermont" contributing to the unique flora of pitch pine, scrub oak or as he calls it "bear oak" because it's the right height for, and is prized by, bears, mountain laurel and various lichens and mosses.
He gives a fascinating account of how such granite domes with their silky smooth undulating surfaces came into existence.
The smooth grey appearance is due to polishing with silt and fine gravel over thousands of years by slowly advancing glaciers when large parts of North America were covered by a miles-deep ice sheet. Some granite slabs are marked by semi-circular deep gouges, called chatter marks, where larger boulders pushed by the glaciers have notched the stone. The chatter marks usually appear in a step-wise fashion reflecting the stuttering progress of the boulders across the stone.
This is not an area where birds are much in evidence except for the ubiquitous chickadees and the occasional turkey vulture. In fact several years ago a friend of ours was lying spreadeagled on the smooth granite with his eyes closed enjoying the sun. When at last he looked up a young turkey vulture was eyeing him, circling slowly over him just above the crown of the pines.
Currently the tops are bearing a rich crop of cones.
Staring up high I discover a red-breasted nuthatch, a species that I haven't seen all summer.
As evening approaches a family of blue jays descend noisily from tree to tree to the valley below.
Note: A wonderful book illustrating the landscape history of New England is "New England Forests through Time -- Insights from the Harvard Forest Dioramas" by David R. Foster and John F. O'Keefe.