48 



MASS. EXPERIMENT STATION BULLETIN 249 



fruit would have been greater if the orchard had been planted to more sus- 

 ceptible varieties such as Duchess, Yellow Transparent, or Gravenstein. 



The results of the 1926 orchard experiments, planned principally to deter- 

 mine the most effective time of application, are shown in Table 16. Other 

 orchard spraying experiments, planned largely to compare materials, are 

 referred to frequently in this bulletin but these are still incomplete in some 

 details and are not reported in tabular form. 



In the spraying experiments reported in Table 16, the applications were 

 made as follows; Pink — May 19; Calyx — June 2; 7-day — June 9; 3-weeks — 

 June 23. 



The materials in all sprays were lime-sulfur solution, 1 gallon in 50 gal- 

 lons of spray; calcium caseinate ^ pound in 50; and lead arsenate 1^ pounds 

 in 50 except in Plat VI where 2 pounds of lead arsenate in each 50 gal- 

 lons were used. 



The spraying program in Plats II-A and II-B was identical, but the dropped 

 apples were picked up during June and July in the former. Plat II-A 

 had 1.02 per cent more clean fruit and showed a decrease of .29 in the aver- 

 age number of stings per stung apple, largely by the elimination of many 

 fall feeding punctures. This benefit is small, but is all that should be ex- 

 Table 16. — Results of Orchard Spraying Experiments, North Littleton, Mass., 



1926. 



Due to the small number of apples on the count trees in Plat VI, harvest 

 fruit from otlier trees in addition to the count trees was examined and 

 included in the record for the plat. Therefore, a comparison between 

 the injury to dropped fruit and the harvest fruit in Plat VI is not sig- 

 nificant. 



