BULLETIN 161 



FUNGICIDES IN THE APPLE ORCHARD. 



Charles Brooks. 



The following bulletin is a summary of rive years of spraying 

 experiments in the apple orchards of New Hampshire. In carrying 

 out the work the control of particular diseases and the action of 

 special fungicides have been kept in view as well as the general care 

 of the orchard. 



THREE YEARS' WORK IN McINTOSH ORCHARDS. 



In the summers of 1907, 1908 and 1909 spraying experiments 

 were made in the Mcintosh orchards of Arthur G. Ladd and Jonathan 

 Smith of Deerfield, X. H. The primary purpose of the work was 

 to determine the relative value of different fungicides in the control 

 of apple scab. In 1908 and 1909 the Bureau of Plant Industry of 

 the U. S. Department of Agriculture co-operated in the work. 



The proprietary mixtures were made up in every case as directed 

 on the package. In describing a Bordeaux* the number of pounds 

 of copper sulfate is given before that of the lime ; thus a 2-4-50 

 Bordeaux contained two pounds of copper sulfate and four of lime, 

 to fifty gallons of water. The sodium benzoate Bordeaux contained 

 one pound of copper sulfate, one of lime and one-half pound of 

 sodium benzoate to fifty gallons of water. 



In 1907 the first spraying was made May 17, just before the 

 flower buds opened, the second June 7, when the blossoms had 

 mostly fallen and a third June 21. The first spraying was omitted 

 on Plot 20. In the Ladd orchard arsenate of lead at the rate of two 

 pounds to fifty gallons was added to all the fungicides except the 

 Pyrox, which already contained an insecticide. In the Smith 

 orchard Disparene was used as an insecticide. 



Notes were taken on the drops August 1, August 27 and October 



*For methods of preparing Bordeaux see Bulletin 157 of the New Hampshire Experi- 

 ment Station. 



