220 



THE MONTHLY BULLETIN. 



The tank was slightly small for the purpose, and as a result a strip 

 only six feet wide could be sprayed at one time. The nozzles were 

 placed 18 inches apart. Two different types of nozzles were used, the 

 two outer being known as the "Friend" type, throwing a circular 

 spray, and the two inside as the "Bordeaux," throwing a fan-shaped 

 spray. Mr. Gould reports a marked difference in the action of the 

 two sprays, stating that the fan-shaped spray gave the best results on 

 the very young mustard and the circular the best on that which was 

 older. 



There was considerable difficulty experienced in securing the field for 

 the experiment. When one was finally obtained the mustard had 

 advanced beyond the stage where maximum results could be expected. 

 The height of the mustard and grain was approximately 18 inches. 



Fig. 4!f. — Field No. 1. at the time of spraying". The mustard is covering fully 

 50 per cent of the field and is about two incites higher than the grain. 

 March 28, 1917. (Original.) ' 



After four acres had been sprayed the owner of the Held volunteered 

 the use of another field on which the grain and mustard were only 

 three inches high. One acre of this field was sprayed with 100 pounds 

 of iron sulphate to the acre. The spray was directed straight down. 

 and with a pressure in the tank of 150 pounds. 



The results of the two experi nts are very encouraging, ami give us 



reason to expect that great good will come to the state through further 

 use of this method of eradication. The results on field No. 1 show a 

 killing of To per cent. As stated before, the spray was put on too late 

 in the season. The leaves of the mustard plant which were touched 

 by the spray were dead inside of twenty-four boors, while the grain 

 remained uninjured. When examined three weeks after spraying, 



