Forest Trees of Illinois (Third Edition)

On the pages following the illustrated glossary are keys to the trees of Illinois. A key is a botanical device which enables the user, through proper selection of a series of choices, to identify a specimen at hand. Separate keys are provided for trees during the spring, summer, and autumn seasons and during the winter season. Begin at the first pair of number 1's, choose the statement that best fits the unknown specimen, and then go to the next pair of statements beneath. Continue this same procedure until the name of the plant is reached.