76 THE REPORT OF THE No. 19 



in the spring my experience leads me to give a decided preference to that 

 which has been put on when the buds were actually bursting, compared with 

 what was sprayed a month earlier. I find that the longer the wash remains 

 on the trees the better the results. Now a spray put on a month before 

 the leaves come out will wash off much more rapidly than that put on when 

 the buds are opening, for the simple reason that, in the latter case, the 

 leaves coming out soon after, break the violence of the rain and to a very con- 

 siderable extent protect the spray. Many other experimenters have found 

 the same result. In Bulletin No. 107 of the year 1906, Prof. Forbes, of 

 Illinois, says, that January applications were only about half as efficient 

 as those made in March. Allowing for difference of climate this would be 

 practically the same thing here as spraying in March compared with the 

 end of April. I found that trees sprayed for Oyster-shell scale on March 

 9th seemed to be but little benefited, whereas a very large per cent, of the 

 scale was killed on those sprayed on May 10th, that is two months later. 

 In every case where I examined trees for either Oyster-shell or San Jose 

 scale I found that those on which the wash had remained longest showed 

 much the best results; and, other things being equal, these were always 

 the last sprayed trees. 



But some one may ask, "How late is it safe to spray?" Personally I 

 think it is perfectly safe to spray until the buds are nearly open. I sprayed 

 a few currant bushes when the leaves were nearly an inch wide, and there 

 were scarcely any signs of injury to the foliage. Apple and plum branches 

 were also sprayed when the buds were almost open ; a very slight sign of 

 their having been burned in some cases around the edge was all the injury 

 I could detect. I have seen a number of plum trees sprayed when the buds 

 had practically burst and yet no injury resulted. In the. Niagara district 

 I made a number of inquiries on this point and in every case 

 got the answer that it was quite safe to spray even while the buds 

 were actually bursting. Peach trees, having a very tender foli- 

 age, should not be sprayed quite so late as more hardy trees, I found that 

 a number of the farmers next year think of spraying, as an experi- 

 ment, a few trees just after the blossoms have fallen. Their object is to 

 see the effect upon aphids, plum rot, and apple and pear scab. Mr. J, W. 

 Smith told me of an interesting experiment that had been performed by his 

 tenant, Mr. R. Doughbrough, on Mr. Smith's farm at Vineland, I called on 

 Mr. Doughbrough and asked him for further information. He said he had 

 sprayed some pear and plum treeS this spring just after the blossoms had 

 fallen. He used the full strength 22 lbs. lime, 16 lbs. sulphur and 40 gals, 

 water, boiled for 45 to 60 minutes. 



The foliage, he claimed, was practically uninjured and was equally as 

 good as that on trees sprayed earlier in the spring. The results upon the 

 scab will be referred to later. Though Mr. Doughbrough was able to 

 spray so late this year without injury, it is very probable that a difference 

 of weather would have caused the spray to burn the foliage severely. There- 

 fore, while it is advisable to spray as late as is safe, all spraying should cease 

 before the blossoms come out. In any case the blossoms and leaves would 

 prevent the spray from covering the bark of the tree thoroughly and so scale 

 or other hibernating insects could not be so effectively controlled. 



The Effect of Rain. 



The question has sometimes been asked whether, if rain comes after 

 spraying, it will be necessary to spray again. The best answer to this ques- 



