New York AGRICULTURAL EXPERIMENT STATION. 279 
between these strengths shown in the three tables given are so 
slight as to be insignificant. The proof is positive, that the greater the 
amount of copper sulphate, the more the bordeaux injury; if, then, 
there be but little difference in the amount of scab on trees sprayed 
with 4-4-50 and 3-3-50, and if this should be in favor of the 
former strength, the less amount of injury from the weaker 
solution may offset the increase in the percentage of scabby fruit. 
This Station has used the 3-3-50 formula in the home orchards 
and in a ten-acre Baldwin orchard near South Greece, with ap- 
parently as good results as when much stronger mixtures were 
used. 
Piel Ce GON (OP RESULTS. 
We have no means of entirely preventing the toxic action of 
the copper salts in spraying fruits with bordeaux mixture. It 1s 
possible, and probable, that we shall discover some fungicide that 
will kill the germinating spores of fungi and not injure the plant. 
Until such a discovery be made, the problem is to spray so as to 
control fungi and yet injure the host plant as little as possible. 
While the investigations at this Station have by no means solved 
this complicated problem, they do afford a basis on which to make 
several practical suggestions to fruit growers. 
Immumty to bordeaux injury—A number of the apples most 
widely known in New York, as set forth on page 247 of this bul- 
fetin, are not injured, or but slightly, by bordeaux mixture. These 
may be sprayed without much fear of injury. On the other hand 
the sorts named as being susceptible to injury must be sprayed with 
“great care. Growers will find it worth while to distin guish between 
varieties in their spraying operations. 
Immunity to scab fungus—A number of commonly cultivated 
apples are nearly immune to attacks of the scab fungus. <A partial 
list of these is: Alexander, Ben Davis, Gano, Hubbardston, Olden- 
burg, Red Astrachan, Rome, Roxbury, Sutton, Tompkins King, 
1olman Sweet, Wealthy, Yellow Newtown, Yellow Transparent. 
All of these, and others possibly, need comparatively light applica- 
tions of bordeaux mixture in the average season. 
Less copper suiphate-— The results of the experiment with 
different quantities of copper sulphate in bordeaux mixture are 
not conclusive enough to lead me to state positively that the firuit 
_ grower can use less of the copper sulphate than in the 4-4-50 
formula now in common use. But the investigation indicates 
