Virtual Nature Trail
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Stream Trail 5 - Nurse TreesAt the entrance to the witch hazel thicket is a fallen white ash tree that has been on the forest floor for many years, and, following the back curve of the trail out of the thicket, you will step over the upper part of this same tree. The trunk of this tree is covered with a continuous blanket of mosses which make a soft, moist matrix on its exposed surface. Seeds of annual weeds, perennial shrubs and even other tree species have fallen into this moss matrix and have generated a successional series of plant growth all along the fallen tree. In forests that are limited by moisture (forests like the maritime forests of our eastern barrier islands would be a good example) trees like this ash would be referred to as "nurse trees." The moisture retaining mosses and rotting wood of these nurse trees provide a focus for successional plant growth and generate the most viable seed beds for subsequent tree growth in these ecosystems. It is amazing to walk about in these dry forests and see straight lines of trees that seem to have been planted by some invisible hand.  Our forest ecosystem along the Nature Trail is very moist and rich in nutrients, so the "nurse tree" phenomenon is not observable here. The richness of the epiphytic plant growth on this fallen tree, though, is most impressive.

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