116 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



gists and plant pathologists have by many experiments determined a 

 schedule of spraying with a combined arsenical insecticide and a fungi- 

 cide — Bordeaux mixture or lime-sulphur wash — which affords a large 

 degree of protection from all of these troubles. To effect the control 

 of insects other than the codling moth and the several fungous dis- 

 eases mentioned requires several applications of sprays, and renders 

 the one-spray method of questionable practical value where these 

 several troubles exist. These differences in fruit-growing conditions 

 between the West and East should be borne in mind in any consid- 

 eration of the practicability of the one-spray method. 



RESULTS OF EXPERIMENTS WITH THE ONE-SPRAY METHOD AS 

 COMPARED WITH RESULTS FROM THE USUAL SCHEDULE OF 

 APPLICATIONS. 



During the season of 1909 the Bureau of Entomology carried out 

 experiments to determine the relative value, in the control of the 

 codling moth and plum curculio under eastern conditions, of the 

 one-spray method in comparison with a schedule of applications 

 requiring a total of from three to five treatments according to locality, 

 representing practically the method of spraying considered best for 

 the localities in question. The work was carried out in three States, 

 namely, in Virginia, in Arkansas, and in Michigan, and included four 

 orchards, thus representing a considerable range in climatic conditions. 

 The field work in Arkansas was under the immediate direction of 

 Mr. E. L. Jenne, assisted by Mr. F. W. Faurot; in Virginia the field 

 operations were under the immediate charge of Mr. E. W. Scott, 

 assisted by Mr. L. F. Pierce, of the Bureau of Plant Industry. Mr. 

 R. W.Braucher was charged with the spraying operations in Michigan, 

 and was assisted a part of the time by Mr. Walter Postiff. The work 

 relating to the control of fungous diseases in each of the orchards was 

 done in cooperation with Mr. W. M. Scott, of the Bureau of Plant 

 Industry. In addition to obtaining data on the effects of the treat- 

 ments on the codling moth and plum curculio, in Arkansas injury by 

 the lesser apple worm was taken into account, which in that section 

 is very troublesome. 



EXPERIMENTS IN ARKANSAS. 



The experiments in Arkansas were carried out in the orchard of 

 Mrs. S. E. Jones in the vicinity of Siloam Springs. The entire orchard, 

 consisting of 344 trees, was divided into live plats, as shown in the 

 accompanying diagram (fig. 34.) Trees of each plat from which the 

 fruit was counted throughout the season for records are designated 

 in the diagram by the same numbers which these trees bear in the 

 table. The orchard, a general view of which is shown in Plate X, 



