Here is select list of subject headings to try searching in the Goldstein Library Catalog. You'll want to try different search terms and strategies as your research develops.
Below is a small selection of books to gather reference images of plants, trees, fungi, and other flora. Helpful sections to browse for additional titles are located in the QKs.
The Complete Mushroom Hunter by 
The Tree in Photographs by 
Trees and Flowers-Insects and Animals by 
Trees of Eastern North America by 
Trees of Western North America by 
