The National Arbor Day Foundation: What Tree Is That?

Imagine a world without trees. Students can click on a barren field to see the transformation of the bare dirt by plants and trees. The authors include an online reference guide that lists the benefits of trees and an excellent alphhabetical tree guide, as well as a "What Tree Is That?" guide to tree identification. Clicking on any tree name provides a picture and a description. Note that states may have different dates for Arbor Day depending on that region's best tree-planting times.