220 +#ReEportT OF THE HorRTICULTURAL DEPARTMENT OF THE 
24. Bordeaux mixture containing an excess of lime, in the ex- 
periments on the Station grounds, did not prevent nor greatly 
lessen bordeaux injury, again corroborating the experience of fruit 
growers. 
25. In a wet season there may be some slight advantage in the 
use of an excess: of lime in that it may delay the fungicidal action 
of the copper salts, an advantage in controlling the scab fungus 
in such a season. 
20. Disadvantages of an excess of lime are that a mixture con- 
taining it is more difficult ‘to apply well and that the fungicidal 
action of the mixture may be weakened in a dry season. 
27. An experiment to show the effects of bordeaux mixtures 
made with varying quantities of copper sulphate and lime, showed 
that, the more copper sulphate, the greater the injury. | 
28. The experiment noted in 27 showed that in general the 
stronger the solution, as to copper sulphate, the better the control 
of the scab fungus. But the differences between the 4-4-50 solu- 
tion and the 3-3-50 one in controlling the fungus were so insigni- 
ficant that it is believed that the weaker one can be used and to 
advantage as it would cause less bordeaux injury. 
29. There are no means of entirely preventing the toxic action 
of the copper salts in spraying fruits with bordeaux mixture. The 
problem is to spray so as to control fungi and yet injure the host 
plant as little as possible. 
30. Practical suggestions for spraying are: Use less copper sul- 
phate; give the 3-3-50 formula for bordeaux mixture a thorough 
trial. Spray in moderation; spray to cover the foliage and fruit 
with a thin film and yet not have the trees drip heavily. So far 
as possible the bordeaux mixture should be used only in dry weather. 
Use equal amounts of lime and copper sulphate. 
31. Some varieties of apples may be sprayed without much fear 
of injury. Others must be sprayed with great care. Distinguish 
between the varieties in spraying operations. 
32. Many varieties of apples are nearly immune to attacks of 
the scab fungus. These need comparatively light applications of 
bordeaux mixture in the average season. 
33. Bordeaux mixture is the best fungicide known to the apple 
grower. Its use cannot be given ,up in fighting the apple scab 
even though it cause some injury; apple scab causes a far greater 
loss than bordeaux injury. 
