NEw YorK AGRICULTURAL EXPERIMENT STATION. 261 
Time of appearance of bordeaux injury.— Four trees in each 
of the eight treated plats were sprayed May 31, the fifth tree in 
each plat being left until it could be sprayed before or during 
a rain. Rain fell on June 5, and the unsprayed trees in the 
plats, a Rhode Island Greening in each case, received their appli- 
cation. Daily examinations of fruit and foliage were made; and 
until the rain on June 5, no trace of injury was to be found. 
The morning of June 5 was clear, bright and hot, but in the 
middle of the forenoon a light thunder storm came up and spray- 
ing was begun on the unsprayed trees in the plats, and was con- 
tinued during the intervals between showers until finished at 
three in the afternoon. The weather continued showery until 
the morning of June 6, the amount of precipitation for the 24 
hours being .74 inch. On the afternoon of the sixth, it was 
found that all of the 4o trees sprayed with bordeaux mixture, 
either on the last day of May or the fifth of June, showed injury. 
Rate of development— TVhe rate at which any disease, physio- 
logical or pathological, of a living organism develops must de- 
pend upon environment, and with plants, upon temperature and 
moisture in particular. The weather following the first appear- 
ance of the injury was warm and moist. From day to day the 
injury, which appeared at first as faint black or brownish specks, 
became more conspicuous. On the ninth of June a severe hail- 
storm did such damage to fruit and foliage that the bordeaux 
injury was partly obscured. On the thirteenth, the observer, 
Mr. Eustace, noted, “At this date it is easy to see that the injury 
is much more pronounced on the plats that have received the 
largest amounts of copper sulphate. It is apparent, too, that 
the injury at this time is more severe on the Rhode Island 
Greenings than on the Baldwins and that it is most severe on the 
trees sprayed during rain.” On June 12, the second applica- 
tion of bordeaux mixture was made, leaving as before a tree in 
each plat to be sprayed during a rain. On the afternoon of 
the fifteenth and the morning of the sixteenth, the fifth trees in 
the plats were sprayed between heavy showers. 
A week of rain* followed the second spraying and the injury 
increased apace from day to day. Notes taken from time to 
time showed that the injury continued to increase on the fruit 
until about July 30, when it apparently reached the maximum 
except as the increased size of the fruit made it more visible. 
* See data on page 270. 
