Students observe pictures provided of tree deaths at the higher elevations on Roan Mountain. In groups students brainstorm possible reasons for deaths. The teacher will provide the following scenario to the students. Frazier fur deaths on the mountain was concerned about the cause of the deaths. The observer noticed that the large trees were dead and the young trees appeared healthy.
Students again discuss possibilities to explain the observations.
The teacher will provide the following information to the students. The observer wondered if the cause of the tree death was due to acid deposition. It was felt that the deep soil had a harmful pH to these trees but not the shallow soil, therefore causing the large trees with deep roots to be affected. Acid deposition could be trapped deep underground because of a layer of clay. Students should design and carry out an experiment that could demonstrate this hypothesis while controlling other variables.