UNITED STATES DEPARTMENT OF AGRICULTURE 



JW9"^Vt. 



BULLETIN No. 408 



Joint Contribution from the Bureau of Entomology, 



L. O. HOWARD, Chief, and the Bureau of Chemistry, 



CARL L. ALSBERG, Chief. 



Washington, D. C. 



October 28, 1916 



EXPERIMENTS DURING 1915 IN THE DESTRUCTION 

 OF FLY LARVAE IN HORSE MANURE. 1 



By F. C. Cook, Physiological Chemist, Bureau of Chemistry, and R. H. Hutchison, 

 Scientific Assistant, Bureau of Entomology. 



CONTENTS. 



Introduction . 

 Methods . 



Page. 

 1 

 2 



General account of substances used. 

 Summary 



Page. 

 3 

 17 



INTRODUCTION. 



This bulletin is a report of experiments on the chemical treatment of 

 manure during 1915, conducted with a view to destroying the fly larva?, 

 therein without injuring the manure for agricultural purposes. As 

 in the experiments previously reported, the cooperative arrangement 

 between the Bureaus of Entomology and Chemistry was continued. 



The experiments carried out during 1913 and 1914 have been fully 

 reported in Department Bulletins 1 18 (1) 2 and 245 (2) and include tests 

 of the larvicidal action of a large number of inorganic and organic com- 

 pounds. Material from several plant sources was included among the 

 organic compounds tested. The results of the experiments during 

 1913 and 1914 pointed to a number of substances having pronounced 

 larvicidal value, but the majority of these substances did not meet 

 the full requirements, viz, (1) cheapness; (2) noninjurious action on 

 the bacterial flora, on the chemical composition of the manure, and 

 on the growth of plants; 3 (3) lack of extremely toxic properties. 



1 Experimental work during the summer was conducted on the farm of the Bureau of Animal Industry 

 at Bethesda, Md., and during the autumn at the Louisiana Experiment Station at Baton Rouge, La. 

 The entomological work at Baton Rouge was done by Mr. J. L. Webb, of the Bureau of Entomology; the 

 bacteriological counts at Washington were made by Dr. L. P. Shippen of the Bureau of Chemistry, and at 

 Baton Rouge by Dr. C. W. Edgerton and Dr. Harry Morris of the State Experiment Station. Thanks are 

 due Dr. W. R. Dodson, Director of the Louisiana State Experiment Station, for facilitating the work 

 at Baton Rouge. 



2 Numbers in parenthesis refer to "Literature cited," p. 19. 



3 A detailed discussion of the effect of boron on plants and plant growth is embodied in an article in the 

 Journal of Agricultural Research, vol. 5, No. 19, page 877, " Boron: Its absorption and distribution in plants 

 and its effect on growth," by F. C. Cook. 



52085°— Bnll. 408—16 1 



