During the course of two years (1949-51) of wildlife studies in the Huachuca Mountains of southeastern Arizona considerable attention was given to the distribution of plant communities as a background for faunal investigations. Intensive ecological studies of plants were not possible because of prior duties but a rather complete analysis was made of major vegetation units. Continuing biological studies in the Huachucas seem to justify making those observations available to other workers. The Huachuca Mountains lie in southeastern Arizona approximately 25 miles east of the city of Bisbee, Cochise County. This area is in the Mexican Highland Section of the Basin and Range Physiographic Province. The southern extremity of the range is intersected by the International Boundary and from this point it extends northwesterly about 20 miles, having a southeastnorthwest axis.