Virtual Nature Trail
Stream Trail - Downed Ash TreeThe trail has turned to the left and climbed up the slope slightly. We have stayed on the left fork and continued through the stands of yellow poplar and white ash. A fallen white ash lays across the trail. It has been cut to allow easy passage along the trail. On the cut ends of the white ash log you can see the tree's "growth rings." These annual growth rings individually represent the yearly cycle of encircling tissue growth (the "vascular cambium" whose principle function is to transport water up the tree) and its inevitable change into strong, supportive wood. A freshly cut tree's age can be accurately determined by counting these growth rings. Further, under certain conditions the relative widths of a tree's growth rings may indicate how "good" or "bad" a particular growing season was. This analysis of ring widths, then, is a tool that can be potentially used to explore the past climatic history of a site through the life spans of its trees. Further, the patterns of these annual rings observed in wooden artifacts (like building materials, wooden tools etc) can be matched up by archeologists to ring patterns of surrounding trees thus enabling a very precise dating of these objects .

Ash tree trunk cut to show growth ringsThe fallen white ash tree in front of us has many annual growth rings. Judging by the condition of the trunk and the absence of moss etc growing on the downed tree, we estimate that this tree fell no more than five years ago.

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