ERADICATION OF BLACK-CURRANT GALL-MITE. 121 



<3Xperiments, and, secondly, the large quantity of soap used. But 

 once having proved that the mite could be destroyed by the use of 

 sulphur, it remained to be demonstrated in what form it was best 

 applied and whether or not it could be shown that any benefit resulted 

 from a smaller number of applications. 



AVith these two objects in view a series of experiments was com- 

 menced early in 11)05 on a piece of land set apai;t and prepared for 

 the purpose by the council of the University of Birmingham. 



On this plat seven rows of Irishes were planted, consisting of Black 

 Xaples, Baldwins, and lioskoop (liant. All were as badly affected 

 Avith •• l)ig l)ud "' as any that couhl l)e obtained: indeed, I have never 

 seen worse. The plat of land was far from an ideal one and the last 

 that a fruit grower Avould have chosen, so that the bushes had no 

 natural advantages in their favor. 



The exi)eriments carried out were as follows: Rows 1, 2, and 3 were 

 dusted with equal parts of unslaked lime and flowers of sulphur. 

 Rows 4, T). and (') were sprayed with a mixture consisting of 1 pound 

 of lime, 1 pound of sulphur, and 20 gallons of water, while row 7 

 was sprayed Avith a mixture consisting of 1 pound of sulphur, 1 

 pound of soft soap, and 20 gallons of water. 



SnitniKiry. — It is very evident that all the bushes benefited by the 

 ap])]ication of lime and sulphur. It would have been better, how- 

 ever, had a little less lime been used (1 part of lime to 2 parts of 

 sulphur has acted as well). In the case of those bushes that received 

 a single dusting, the big buds were considerably reduced in nu.mber. 

 not more than one-fourth of the number being present in October 

 as there were in February. Where two dustings were given, a dis- 

 tinctly nuirked diminution over those receiving one dusting was 

 shoAvn, while where three dustings were applied the mite was almost 

 exterminated. It must be borne in mind that neither a spray fluid 

 nor dry application will reach the eggs in the buds, and it seems clear 

 that the number of adult mites wdiich successfully migrated from 

 the old buds into the new ones was very small indeed. In all cases, 

 the mites found were innnature specimens. 



Spraying with Jhnc and HiilpJnir. — The results obtained by spraying 

 wei-e not so good as those by dusting. A large number of buds were 

 affected, and in many of them there were adult and imnuiture mites 

 and eggs. The differences between the one, Iavo, and three applica- 

 tions of the spray fluid Avere quite in keeping Avith those foinul to 

 obtain Avhere dusting had been done. The fcAver the apj^lications 

 the more buds affected and the greater the number of mites. 



Spraying irifh soft soap and sulplnir. — Ivoav 7 was sprayed tAvice 

 Avith the spray fluid above mentioned. When the bushes Avere ex- 

 amined in October a fairly large number of big buds was noticed: 



