New York Agricultural. Experiment Station. 203 



to 40 when the density of the concentrate is 32° Beaume), it 

 was diluted at the rate of two gallons of the concentrate to 

 fifty gallons of water. 



The bordeaux mixture used was prepared from stock solutions 

 and according to the 6-4-50 formula, thereby containing six 

 pounds of copper sulphate and four pounds of unslaked lime in 

 each fifty gallons. 



The arsenate of lead used for the control of bugs was in the 

 form of a thick paste and was used at the rate of three pounds 

 to fifty gallons of the spray mixture, or to fifty gallons of water 

 in the case of the check rows. 



time and number of applications. 



On July 9, when the plants were about six to eight inches high, 

 the first application of the two sprays was given. This was re- 

 peated every two weeks until the vines were entirely dead. Six 

 applications in all were made during the season. 



In order to control the Colorado potato beetles or "' bugs," 

 arsenate of lead, at the rate of three pounds to fifty gallons of 

 the spray mixture, was added and applied with the first two spray- 

 ings. On these same dates the check rows were sprayed with 

 three pounds of arsenate of lead in fifty gallons of water. 

 Following the first spraying it was found that the bugs were 

 not as efficiently controlled on the lime-sulphur rows as they were 

 on the other rows. The cause of this is uncertain, but was 

 perhaps due to a lack of care in mixing the lime-sulphur and 

 arsenate of lead. In order to control the bugs it was neces- 

 sary to spray the entire field again in two days with three pounds 

 of arsenate of lead in fifty gallons of water. This spraying and 

 the addition of poison in the next regular spraying completely 

 controlled the bugs for the entire season, and the use of a poison 

 was thereafter discontinued. 



Both of the spray mixtures were applied with a knapsack 

 sprayer, which permitted a very thorough spraying in every case. 

 The rate of application varied from 150 to 200 gallons per acre, 

 depending upon the size of the plants, and the season. 



