A similar approach has been used with physical materials such as lake varves, annual ice layers in glaciers and calcite deposition rings in cave stalactites. Essentially, we are using limiting factors to tell us about the past. In this lab you will learn a little essential tree anatomy, how to date a disturbance event, and how to interpret a tree ring record in terms of ecological change. Examine a disk from a felled tree to understand its growth mechanism. Examine several specimens from trees damaged by disturbance events, and draw conclusions about the dates of those events.
Reaction wood is abnormal wood formed in leaning stems and branches in trees.
It is denser and more brittle. The elucidation of past climates from tree rings. A usually whitish false growth ring caused by a late spring frost. The frost damages the foliage, and the tree ceases growing and then usually resumes growth later in the season. The later-formed portion of the growth ring that is often characterized by smaller cells with thicker walls.