LIME-SULPHUR PREPARATIONS FOR APPLE DISEASES. 13 



The lime-sulphur sprays Tailed to control apple blotch {Phijllosticta 

 solitaria), which is the most troublesome disease of that section. 

 About 95 per cent of the unsprayed fruit was aflected with blotch 

 and about 40 per cent of the fruit sprayed with the self-boiled wash 

 was so affected. The commercial solution at 1-30 gave only slightly 

 better results, while Bordeaux mixture almost completely controlled 

 the cHsease. Bitter-rot {(llomerella rvfomaculans) , though not very 

 serious in the experimental orchard, was only partially controlled by 

 any of the lime-sulphur sprays, while Bordeaux mixture held it in 

 check thoroughly. It seems from the test that the lime-sulphur 

 preparations are of doubtful value in the control of apple blotch and 

 bitter-rot; but of course further tests are necessary before final con- 

 clusions can be reached. 



CONCLUSIONS. 



The writer feels that the information at hand is not quite sufficient 

 upon which to base final conclusions and recommendations. It 

 seems evident, however, that a lime-sulphur preparation in one form 

 or another is destined, largely, to take the place of Bordeaux mix- 

 ture in spraying varieties of apples subject to serious injury from 

 apj)lications of the latter. 



A lime-sulphur solution containing, when diluted, about 4 pounds 

 of sulphur to 50 gallons of water appears at present to be the most 

 promising preparation. This may be obtained by using the com- 

 mercial solution at the rate of 1^ gallons to 50 gallons of water, or by 

 preparing the lime-sulphur solution at home and diluting it so that 

 each 50 gallons will contain 4 pounds of sulphur. The mixture at 

 this strength injured apple foliage in Virginia very little, and if these 

 results could be taken as a reliable guide there need be no hesitancy 

 in using it; but under difl'erent conditions the results might be differ- 

 ent, and the matter must still be considered as more or less experi- 

 mental. A strength of 1\ gallons of the commercial solution may 

 prove to be sufficient in most cases, and the danger of injury would 

 then, perhaps, be entirely eliminated. 



Our experiments of 1908 and 1909, as well as the published records 

 of other investigators, show that the lime-sulphur solution is appar- 

 ently as effective as Bordeaux mixture in the control of apple scab. 

 Under more severe conditions than those which existed in the exper- 

 imental orchards the treatment might fail; but at present it is very 

 promising. Lime-sulphur will control leaf-spot and other minor 

 troubles, as well as apple scab, but so far it has not proved to be a 

 satisfactory remedy for apple ])lotch (Phyllosticta) and bitter-rot. 

 However, the experiments on those two diseases have not been car- 

 ried far enough to determine what may be expected of it in this con- 

 nection. In sections where spraying for bitter-rot is required the 



[Cir. 54] 



