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station to be an eliecti/e remedy for the plum wart {riowrUjhtia mor- 

 bosa) it w.'is tried ou a larger scale in 1890, with good results. 



In its application we have found that, unless used with great care, the snialhir 

 hranches wore destioycd. Tiio past season we have overcome this difficulty by 

 a})plying the keroseuo mixed with some pigment to form a thiu paste so that it would 

 not spread over the branches. » # * 



To be effectual this appHcat ion must be made as soon as the wart begins to enlarge, 

 which is sliown by a swelling on or under the bark, generally of a light brown color 

 wlien the bark first bursts open, but becoming darker as it increases in development. 



Tiie kerosene paste is best applied with a small, pointed paint brush, and should bo 

 used on the wart only. 



Examination of the trees nuist be made at intervals of from 2 to 4 weeks, according 

 to tlie state of tlie weather. 



If the weather be dry and clear few warts will be started, while if moist and warm 

 they develop more abundantly. 



In the hope of finding some method of destroying the warts which 

 would require less labor, .suli)liate of copi)er (1 j)ouud. to 22 gallons of 

 water) was sprayed on plum-trees April 19; sul})hate of coi)per with 

 Paris green (1 pound to 500 gallons). May 17 ; Bordeaux mixture and 

 Paris green six times, irom May 21 to July 29. 



Owing to the destruction of the fruit and the foliage by the first application [where 

 Paris green was used], positive results could not be deterujined as to the effect of the 

 Paris green upon the curculio, l)nt in the case of trees that were treated with the 

 Bordeaux mixture and Paris gicen only, a very large crop of fruit was matured, while 

 other trees not treated lost all their fruit from the attacks of the curoulio. The 

 number of warts was very decidedly less where treated with the copper mixtures than 

 where untreated. 



One thing our experiments have demonstrated beyond a question, i. e. that plum- 

 trees, leaves and branches, may be kept covered with mixtures of sulphate of copper, 

 lime, and Paris green, for nearly the entire season without noticeable injury and we 

 believe that both the plum wart and plum curculio may be held in check by tliis 

 remedy. Auother season it is hoped that experiments may be made on a large scale 

 in different localities thnnighout the State, to settle the question. 



Experiment No. 5 — Bordeaux mixture for grape mildew and rot. — in 

 the station plats are planted two vines ea(;h of about 100 varieties of 

 grai)es. Of these vines, one of each variety was treated and the other 

 left as a cheek vine. Some of these varieties have n»)t fruited, but 42 that 

 l)roduced fruit in sufficient quantity for comparison are mentioned in a 

 table, with data as to time of ripening, color, and quality of fruit, and 

 the etlect of treatment on mildew. The canes were painted with a 

 strong solution of sulphate of copper, April 2 and 3, and sulphate of 

 copper (1 pound to 22 gallons water) was applied May 29. 



Soon after this application it was found that the foliage was seriously injured, and 

 the next ajiplieatiou, nuide June 20, was of the Bordeaux mixture. As the rose-bugs 

 were beginning to work, 1 poniul of Paris green to 500 gallons of the mixture was 

 added to this, and other applicatioiis were njade July 19 and 28. The Paris green 

 had no effect upon the rose-bug, and hand picking was resorted to to save the crop, 

 but the effect of the Bordeaux mixture was so marked that at a long distance it was 

 visible, not only preventing the mildew on the leaf, but the rot of the berry, to which 

 eoine varieties are almost invariably subject, 



31500— No. S 3 



