1922.] The Hop Control. 1047 



spraying was given about a fortnight to three weeks later 

 according to the suitability of the weather. 



The crop was grown under the ordinary field conditions in 

 ridges 30 in. apart and 14 in. between the sets. The manur- 

 ing each year was constant, while a modified Bordeaux mixture 

 was the spray adopted in each case, the ingredients used being 

 14 lb. of copper sulphate and 9 J lb. of lime to 100 gallons of 

 water. Approximately 100 to 120 gallons of mixture were 

 applied per acre at each spraying. 



The following figures show the average yields per acre 

 recorded throughout the trials, together with the average 

 percentage of diseased tubers (by weight), and the average 

 percentage of sound seed (by weight) of the total crop : — 



Not sprayed. Sprayed once, Sprayed once, Sprayed txrice 

 early. late. early and late. 



tons. cwt. tons. cwt. tons, cwt. tons. cwt. 



Average yields per 

 acre for 9 years, 



1911-20 7 §| 8 4 8 4 8 lOi 



percentage. percentage. percentage. percentage. 



Average percentage 

 of diseased tubers 



for the period ... 5*49 5'44 4'03 4 09 



Average percentage 

 of seed tubers for 



the period 19-78 19-57 18-79 18-43 



The conclusions to be drawn from this experiment show that 

 not only has spraying increased the total crop on the average, 

 but it has also increased the percentage of sound saleable ware 

 tubers. 



The percentage of seed by weight shows a small reduction 

 in the case of the sprayed plots, while on the chats spraying 

 caused a definite reduction in percentage occurrence. 



Spraying also reduced the percentage occurrence on the 

 average of diseased tubers on all the plots and particularly in 

 the late sprayed and double sprayed plots. 



****** 



The Hop Control, which consists of a Board or Committee 

 composed of representatives of hop growers, merchants, factors 

 Th<* Ho anC ^ Drewers ? acting under the chairman- 

 Control S ^ °^ ^ on ^ ro ^ er ' was established 

 by a minute of appointment of the President 

 of the Board of Agriculture, dated 6th October, 1917, in order 

 to secure the restoration of the English acreage under hops 

 which had been reduced bv earlier orders during the War. The 



