At 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.
....
At 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.
