Publisher's Synopsis
The key is based on summer characters, primarily those of leaves, the most important of which are defined on pages 22-24 and illustrated on the inside covers. The illustrations were prepared by Jane W. Roller. At times the identification of a species is facilitated by the use of flower, fruit, bud, leafscar, habit, and habitat characters, but also they are usually not required. The key is artificial, no attempt having been made to reveal phylogenetic relationships.