Biologists and those interested in allied lines are familiar with the movement launched by the Ecological Society to secure the preservation of socalled natural areas where plant and animal life and natural features in general may remain undisturbed by human activities. In seeking such conditions one naturally turns to localities remote from established communities. The National Forests hold out much promise because they contain large sections which as yet are but little affected by industrial development, and because they are under Federal control. The writer has been requested by the chairman of the Committee on Preservation of Natural Areas of the Ecological Society to list the National Forests of Arizona and New Mexico as areas which will remain at least in a semi-natural state. Within these two States are I5 National Forests, whose combined area is nearly 22 million acres. Vegetation zones range from desert or semi-desert at from 3,000 to 4,000 feet in elevation to alpine conditions above I2,000 feet. With rising altitude, the plant associations pass successively from desert grasslands to brushlands, woodlands, yellow pine forest, Douglas fir-white fir forest, Engelmann spruce forest, and finally to treeless areas above timberline. The two extremes of desert and timberline do not often occur within the boundaries of the same forest, although this is the case in several instances. It is of interest to consider in what measure the National Forests under the existing methods of management will answer the requirements for Natural Areas. The general policy governing the handling of National Forests is that of highest use to the public. The primary purpose is the production of timber. This implies that when a forest crop is mature it will be harvested. Associated with timber production is the utilization and development of grazing, agriculture, water, mining, recreation, and other resources. Cutting disturbs natural forest conditions in a degree which varies with the type of forest and with the method of management. Under all systems of management practiced in the Southwest, natural reproduction is the first consideration. Mature and over-mature trees are removed unless needed for seed production, shelter to seedlings, or to control streamflow and erosion. Between the seedling stage and the mature stage are considerable numbers of thrifty young trees which will be ready for cutting before the seedlings reach 1 Read before the second annual meeting of the Southwestern Division of the American Association for the Advancement of Science.