. Bulletin of the Department of Agriculture. Agriculture; Agriculture. UNITED STATES DEPARTMENT OF AGRICULTURE. BULLETIN No. 1115 fMI jrwV Washington, D. C. November 28, 1922 CHEMICAL CHANGES IN CALCIUM ARSENATE DURING STORAGE. By C. C. McDonnell, Chief, and G. M. Smith, Assistant Chemist, Insecticide and Fungicide Laboratory, Miscellaneous Division, Bureau of Chernistry, and B. R. CoAD, Entomologist in Charge, Delta Laboratory, Bureau of Entomology} CONTENTS. Purpose of investigation 1 Results of previous investigations 2 Results of present investigation 3 Discussion 23 Summary 27 PURPOS
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. UNITED STATES DEPARTMENT OF AGRICULTURE. BULLETIN No. 1115 fMI jrwV Washington, D. C. November 28, 1922 CHEMICAL CHANGES IN CALCIUM ARSENATE DURING STORAGE. By C. C. McDonnell, Chief, and G. M. Smith, Assistant Chemist, Insecticide and Fungicide Laboratory, Miscellaneous Division, Bureau of Chernistry, and B. R. CoAD, Entomologist in Charge, Delta Laboratory, Bureau of Entomology} CONTENTS. Purpose of investigation 1 Results of previous investigations 2 Results of present investigation 3 Discussion 23 Summary 27 PURPOSE OF INVESTIGATION. Soon after calcium arsenate had been introduced into the Cotton Belt for use in the control of the cotton boll weevil, the United States Department of Agriculture began to receive complaints of injury to cotton plants resulting from the application of this material. Chemi- cal analyses showed that much of the calcium arsenate being used in the cotton-growing region at that time contained from 1 to 5 per cent of ''water-soluble" arsenic oxid,^ which explained to some extent the injury that was being done to the plants. In an endeavor to place the responsibility for this unsatisfactory condition, it was suggested that perhaps commercial calcium ar- senates deteriorated somewhat when stored for a period of several weeks or months and that this deterioration was more rapid under the climatic conditions existing in the cotton-growing States. This problem was a very serious one, not only from the standpoint of the consumer but from that of the manufacturer as well, for on its solution depended the answer to the question whether or not it was 1 L. N. Markovitz and A. Shaver, junior chemists, of the Bureau of Chemistry, assisted in the analytical work, and T. P. Cassidy and M. T. Young, of the Bureau of Entomology, cared for and sampled aU the material stored at TaUulah, La. 2 As determined by the official method of the Association of Official Agricultural Chem
Size: 1698px × 1472px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauth, bookcentury1900, bookdecade1910, booksubjectagriculture
