Lesson overview: In this activity, students create a graphical model of forest communities in the north western Sierra Nevada. They create the model using a table that describes the current distribution of tree species on a fictitious mountainside called Sasquatch Peak. Students then use the model to describe the species composition of current forest communities and to predict the potential effects of changing climate conditions on the distribution of species.

Goals: To increase students’ understandingthat

• forest communities develop under specific environmental conditions
• species with similar needs are likely to occur together
• species distributions and community composition may change as climate conditions change
• models can be used to describe what we understand and predict what may happen in the future

Objectives:

• Students can list tree species that are likely to occur together in montane forests of the Sierra Nevada
• Students can use a graphical model to predict some changes that could occur as climate conditions change.