Sunday, February 15, 2009

The picture on top taken in 1968 is looking from south to north on the Gale River Trail. The boulders just to the left of center in the photo are the same ones in the photo below it (2nd one down) taken 2-14-09. And the single rock with my poles leaning against it in the bottom photo can be seen in the 1968 photo as well, just behind the two boulders. If you compare the two photos, the one above and this one you can see how much vegetation has re-colonized the slide track.

Comparing the black and white photo from 1974 and the color slide from 1968 you can see two types of re-vegetation occurring within 15-20 years after the land slide. In the black and white photo, near the top of the slide filling in on both sides of the slide you can see poplar (Populus tremuloides) and alder (Alnus rugosa) invading inwards to cover the open ground. In the foreground of this picture you can also see some balsam fir and alder seedlings.

In the color slide from 1968 you can see extensive herbaceous cover everywhere between the rocks and in the immediate foreground. This cover includes some birch (Betula minor), poplar, asters, sedges, mosses, and there's lichen visible on the rocks as well. As in the study from Muir Inlet also found that immediately after the "event", when the top soil and the A1, A2, and A3 horizons haven't evolved yet, specific plants will colonize the disturbed ground almost immediately and begin the process of soil development necessary to "stabilize" the site.

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