Spraying 2,4-D by Airplane on Sand Sagebrush and Other Plants of the Southern Great Plains

Abstract

EXXTENSIVE tests were made in May 1947 and 1948 of the airplane application of 2, 4-D (2 ,4-dichlorophenoxyacetic acid) on sagebrush infested rangeland near the U. S. Southern Great Plains Field Station, Woodward, Oklahoma. These studies followed successful trials of hand spraying 2, 4-D on rod-square plots of sand sagebrush (Artemisia filifolia Torr.) in May, 1946. The testing of chemicals was started after extensive studies by the Station since 1937 had shown conclusively that eradication of sand sagebrush by mowing is an extremely effective range improvement practice. Studies of vegetation and grazing tests during the past 10 years have shown that removal of sand sagebrush by mowing in two successive years during June increased grass density 90 percent, carrying capacity 45 percent, gain per head 14 percent, and gain per acre 78 percent, as published in semi-annual progress reports of the Station and elsewhere (2). Although mowing was highly effective, it was too slow and costly to be widely used on large tracts of low-priced rangeland. The new chemical 2,4-D sprayed by airplane promised to overcome both of these important objections. The results reported herein are based on investigations conducted by the Division of Forage Crops and Diseases, Bureau of Plant Industry, Soils, and Agricultural Engineering, and the Bureau of Animal Industry, Agricultural Research Administration, U. S. Department of Agriculture, in cooperation with the Oklahoma Agricultural Experiment Station. In this study, the authors are indebted to J. R. Harlan, Bureau of Plant Industry, who actively participated in all phases of the tests in 1947; to A. L. Brown, formerly of the same agency, who was in charge of the spraying work in 1948; to J. E. Webster and V. G. Heller, Oklahoma Agricultural Experiment Station for conducting root reserve studies of the shrubs; and to W. H. Black, Bureau of Animal Industry, for cooperation in the grazing studies.