134 THE POTATO 



creased by spraying, due to increased vigor of 

 the plants. At the Vermont Experiment Sta- 

 tion, 1 in 1900, the yield was increased 73 bushels 

 per acre by spfaying, although blight did not 

 appear that year. 



Time of Spraying. Thoughtfulness, thorough- 

 ness, and timeliness are essential to success. A man 

 must watch his crop, the season, and conditions; know 

 for what he is spraying, and do it intelligently as well 

 as thoroughly. In wet years spraying should begin 

 earlier than in dry. The first spraying should be given 

 early enough to ward off the first attack. At Vermont 

 Experiment Station, in 1900,* three applications were 

 most economical, but the first one, that of July 26, was 

 the most important, as half the entire gain was due to 

 it; the sprayings on August 17 and September 8 were 

 of about equal importance. At the same station, 8 in 

 1903, one timely spraying on August 10 insured again 

 of 124 bushels per acre. Some growers who sprayed 

 twice in July secured little benefit, because by the time 

 the blight appeared, the latter half of August, their 

 plants were unprotected. No rule can be given; each 

 man must watch for himself. In some districts it is 

 profitable to give the first spraying when the plants are 

 6 inches tall, and repeat every ten to fourteen days, or 

 as conditions demand. 



Number of Sprayings. At (N. Y.) Geneva Ex- 

 periment Station, 4 in 1903, spraying potatoes five times 

 gave an increase of 30 bushels per acre over three times, 

 and three sprayings increased the yield 88 bushels per 



Vt. Report, 1900, p. 272. Vt. Report, 1900, p. 273. 



Vt. Bui. 106, p. 231. * (N. Y.) Geneva Bui. 241, p. 262. 



