Tree identification can be REALLY involved. Most keys have over 50 question in the flow chart. However, I ran into one on about.com that was much shorter and adapted if for our homeschool. Download below.
Tree ID page
Coloring images for each tree, courtesy of Clemson, that we use to make mini books. They’re already four to a page!
Extra images you will need to complete mini-books if you use my cards (may be still missing two, but I’ll fix it later.):