DITISIOX OF HORTICULTURE 739 



SESSIONAL PAPER No. 16 



to not giving close enough attention to the early sprays before blossoming. It seems 

 very desirable to give one thorough spray just after the leaves are nicely out and 

 another before the blossoms open. Thorough work at this time is of utmost import- 

 ance in order properly to protect the foliage from disease. 



Tlierc seems to be no advantage in using a dormant spray. A slight reduction of 

 ap])le scab apparently followed the dormant application in many instances but the 

 difference between the plots where the dormant spray was used, and the regular with- 

 out the dormant spray is so little that it would not be of economic advantage. It also 

 appears that there is no advantage in using a strength greater than the regular 1-008 

 specific gravity test. The practice of making the early sprays stronger than the regu- 

 lar summer spray does not seem to be necessary for scab control. 



A number of tests have been made with the soluble sulphur as compared with lime- 

 sulphur and the results are rather conflicting. The control of scab was fairly good at 

 Bridgetown and Falmouth, but was not satisfactory at Berwick. It would appear that 

 soluble sulphur does not adhere to the foliage as well as lime-sulphur and heavy rains 

 following soon after the application may very materially lessen the effectiveness of 

 the spray and cause burning. 



The foliage injury resulting from the soluble sulphur when combined with arsen- 

 ate of lead renders this spray quite unsatisfactory. As pointed out last season the 

 neutral leads do cause less burning than the acid leads but the amount of burning 

 v/ith neutral leads is too great to make the question of kind of arsenate of lead a factor 

 of great consequence. It would seem that some quite different insecticide Vpill have to 

 be used with soluble sulphur before it can be considered a satisfactory spray. 



Different preparations put in the soluble sulphur arsenate spray to eliminate the 

 foliage injury have improved the spray somewhat in this regard, but are not considered 

 to be of sufficient value to be of practical use. 



It would appear from what can be gathered up to the present that four thorough 

 applications of lime-sulphur-arsenate, two sprays before blossoms and two after will 

 prove the most satisfactory and ensure practically clean fruit with little foliage in- 

 jury. With much dark damp weather during the spraying period or following a 

 thorough application some injury is liable to result from lime-sulphur but this injury 

 usually is only very slight. The injury seems in every case to be due to the combina- 

 tion formed from the arsenate of lead and sulphur compounds when the two are 

 mixed together and these compounds after they have dried on the trees are influenced 

 again apparently by the weather following the application. 



I am indebted to my assistant Mr. R. D. L. Bligh for the records secured at 

 Berwick and Falmouth, and to Mr. M. P. Pike for the records obtained at Bridge- 

 town. We have made every effort to avoid error in the work and have duplicated 

 the experiments at each orchard as much as possible. 



In considering these results it should be kept in mind that we depend entirely 

 upon the hydrometer test in making our lime sulphur sprays. Were all brands of 

 commercial concentrated lime-sulphur of the same density this would be unneces- 

 sary, but there may be a variation in density of from 1-26 to 1-30 in this product 

 in which case a gallon of the 1-26 specific gravity concentrate if added to 40 gallons 

 would give a much weaker spray than if one gallon of the 1-30 specific gravity con- 

 centrate is added to 40 gallons. The method to follow is to first test the concentrate 

 one is using. 



We were using the Grasselli concentrated lime-sulphur which gave I-'SO specific 

 gravity test. In order to find out the dilution required for a spray of 1-008 density the 

 decimal of this spray is divided into the decimal concentrate thus: — 



(l)-300 



37^- gallons. 



(l)-008 



Kentville. 



