BULLETIN 252 



APPLE SPRAYING EXPERIMENTS IN 191 5 * 



W. J. Morse. 



The 191 5 apple spraying experiments at Highmoor Farm, as 

 in the past, were conducted with the Ben Davis variety. The 

 number of trees involved was 216, or 9 plots of 24 trees each. 

 Each plot consisted of 4 parallel rows of 6 trees to the row. 

 The trees are now between 25 and 30 years old and those used 

 for experimental purposes are in a fairly uniform and vigor- 

 ous condition. 



Treatment of the Plots. 



The following is the spraying treatment outlined for each 

 separate plot. The dates of application are given on p. 171. 

 Plot 1. Standard dilution lime-sulphur, plus one pound of 



dry arsenate of lead in 50 gallons. f 

 Plot 2. Blossom bud application omitted, otherwise like 

 Plot 1. 



*The present publication constitutes the sixth annual report of re- 

 sults obtained from a series of apple spraying experiments at High- 

 moor Farm. Previous reports may be found in Bulletins 189 (1911), 

 198 (1912), 212 (1913), 223 (1914), and 240 (1915) of this Station. 

 For the first two years these experiments were conducted by Mr. W. W. 

 Bonns, then Station Horticulturist, but since then they have been under 

 the general supervision of: the writer. They are planned to cover an 

 indefinite series of years, the object being to secure data regarding 

 sprays and their effects upon the apple as influenced by Maine condi- 

 tions. A summary of the results obtained during the six successive 

 seasons will be found in Bulletin 249 of this Station. 



tBy standard dilution is meant the equivalent of 1 gallon of a 33 ° B. 

 lime-sulphur concentrate diluted with 40 gallons of water. For a 20 

 per cent stronger dilution, one-fifth more of the concentrate was used 

 for making a given amount of spray than was used for making the 

 standard dilution. 



