Williams news., 1904-07-23
FORESTS OF ARIZONA
Study of the Great San Francisco
 Mountains Reserve

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 Realizing how vital to the well fare of a nation is the preservation of it's forests, the United States is making an endeavor to study and improve the forests of this country while there is yet time to preserve them. In furtherance of this work the United States geological survey has just published Professional Paper No. 22, which bears the title Forest Conditions in the San Francisco Mountains Forest Re serve, Arizona" This paper em- bodies the results of the investiga- tions made during 1901 and 1902 by Messrs. John B. Leiberg, Theo- dore F. Rixon and Arthur Dodwell and is prefaced by an introduction written by MT. F. c. Hummer, which is particularly interesting.
 The San Francisco Mountains forest reserve comprises portions of the broad summit and slopes of an elevated tract of land in north central Arizona, which includes the southern part of the Colorado plat eau. The northern part of the area is dotted by several hundred vol canic cones and the southern part is gashed by numerous deep can yons. The altitude of the region ranges from $500 feet at Oak creek in the southwestern portion, to 12, 794 feet at the summit of San Fran cisco peak.
 Among the coniferons trees in the reserve the yellow pine constitutes over g per cent of the entire forest. The aspen takes first rank among the broad leafed species, but has q close competitor in the oak. The chief lumber tree at present is the yellow pine, which is extensively cut and furnishes all of the mill timber sawed, used in, and export ed from the region. Its average total height is S5 feet, with about 10 feet of clear trunk. The diam eter average is IS inches, which corresponds to an age of 1SO years. In the S12, 300 acres of forest area examined, 2,743,55sOOO feet of B. M. of standing timber was found, which gives an average of only 3,377 feet B. M.. per acre. It is ev- ident that the yellow pine stands, even where entirely untouched by the axe, do not carry more than 40 per cent of the timber they are ca pablo of producing. This condition is chiefly attributable to the nu- merous fires which have swept over the region, destroying seedling and sapling growth.
 The chief agencies through which the forests in the reserve suffer de- struction are cutting, grazing and fire. Logging operations have been carried on in most of the central forested areas that are tributary to railroads. The forest has been culled or cut from 14S,S45 acres. The timber cut on these tracts has been converted into tie. stull or round mining timber and saw logs.
 Grazing, especially sheep herd ing, is ruinous to the seedling growth of a young forest. Sheep are especially fond of young aspen, which springs up as the first re- stockage on the non-forested park lands at the base and on the slopes of San Francisco mountains. It was found that the destruction of seedlings on any particular tract of land ranged from 30 per cent to total after A single passage over such ground by 2OOO head of sheep.
 Fires have been of frequent oc- currence in all portions of the re serve The badly burned areas, on which the destruction has been 60 per cent or more, aggregate 6,79O acres. The origin of fires in recent years may, in part, be ascribed to the carelessness of sheep herders,