THE MOXTHLY BULLETIN. 447 



for the absence of fungi, which develop with difficulty under such 

 conditions. 



No rain fell from April 1st until May 24th. From that date until 

 July 24th there was a total precipitation of but 5.1 inches, and the total 

 rainfall from April 1st to September 29th was only 15.1 inches. 



The season was also marked by an extraordinary heat wave during 

 the first tw^o M^eeks of July. INTaximum shade temperatures ranged 

 during this period from 95 to 103 degrees Fahrenheit — a condition 

 which those of you who are familiar with New England weather will 

 recognize as record breaking. As a result of this extreme heat much of 

 the fruit on the south and southeastern sides of the trees, especially 

 where well exposed, suffered severe sunburn. 



I have mentioned this unusual heat factor and the resulting burning 

 of the fruit because of its relation to the spraying question. The final 

 application of spray occurred shortly after the subsidence of the heat 

 wave. A small amount of russeted fruit was again found this year on 

 the several plots as well as in unsprayed orchards in the vicinity of the 

 experimental farm. It was negligible in amount and degree. But the 

 fact is worthy of note that it was more severe on those apples which 

 were injured by sunburn, and that the sunburned areas themselves 

 showed further injury after the third spraying. Furthermore, this 

 additional injury was equally severe on the sunburned fruit of all plots, 

 regardless of the chemical nature of the spray applied. 



A comparison of the lime-sulphur and Bordeaux plots for this season, 

 aside from the question of insect and fungus control, again demon- 

 strated the superiority of the former. Here had been a season, so far 

 as weather was concerned, which was least liable to produce Bordeaux 

 injury ; and yet a noticeable amount of damage was done to both leaves 

 and fruit, aside from sunburn. The fruit and leaves of the other plots 

 were unusually fine, the fruit being of extra size, splendid color and tex- 

 ture of skin. 



What deductions may we feel warranted in drawing from the results 

 of the two years of experimental work just described? In view of the 

 equal damage done by different sprays on the sunburned fruit in 1911, 

 and the approximately equal amount of russeted fruit on sprayed and 

 unsprayed trees in 1910, it appears evident that spray injury may be, 

 and very likely is, due as much to a physical factor as to any chemical 

 action of the materials comprising the spray; bearing in mind at the 

 same time that there is a definitely determined type of injury in the 

 case of Bordeaux mixture which is largely due to its composition. The 

 physical factor mentioned is involved in the application of a spray or 

 mist to growing plant tissues under extreme, or some now undetermined, 

 but unfavorable meteorological conditions. 



Granting the greatest amount of injury obtained under the conditions 

 of 1911, the damage from the commercial standpoint was negligible in 

 comparison with the advantage of annual crops of clean, worm-free 

 fruit. Spray applications must, of course, be made at fairly definite, 



