The key and accompanying list include the trees known to be native or naturalized in Tennessee.
Species known to occur in the Great Smoky Mountains National Park are indicated by an asterisk (*) before the name.
Certain species not native to the region, some of which escape from cultivation, are included but are so designated by CAPITALS.
The present key is an expansion of the Summer Key to the Trees of Eastern Tennessee by the same authors, Jour.
Tenn. Acad. Sci 22:114-133, 1947, which was based on ten years of experience with the key prepared by Stanley A.
Cain in 1937, for use in introductory botany classes at the University of Tennessee.
It is in many places a recognizable descendant of Cain's key and the obligation is acknowledged with sincere appreciation.
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.