1,56 .lonnial of Aiiriciilttirc. \'irtnri,i. [ 10 i\J aiU'H, li> 1!». 



lime sulphur, and tlic-se have been applied with vavying results; but those 

 obtained from the use of the former have, in the opinion of the writer, 

 ber-n, on the whole, the more generally satisfactory. Owing mostly to 

 the weather conditions which largely govern the growth of black spot, 

 it is_ difficult to determine year after year the correct time, or when the 

 bloom is in the jiroper stage to receive the first spray. Various results 

 rnny folloAv the a])plication of a spray mixture used at the same strength 

 in the same orchard during a series of years on blooms having arrived 

 at a like stage of development. The irregularities in the results obtained, 

 a])art from the influence of tlie weather conditions i)revailiug at the time 

 of spraying, are largely due to the number of ascospores present and the 

 variation in the time of their liberation from the asci. It is evident that 

 certain obscure influences retard, while others facilitate, the rii)ening 

 of the spores, and it is reasonable to conclude that spraying should 

 commence as soon as the ripe stage is reached. 



Some of our apple-growers spray twice to cope with the early infec- 

 tion. Plate 193 shoAvs two stages of the Kome Beauty blossom, and 

 those applying Bordeaux mixture mostly use the 6-4-40 strength about 

 the time the blossom is in the condition of Fig. 1, and a 6-4-50 spray 

 when the Fig. 2 stage is reached, or a little later. The majority of 

 growers, however, only spray once — at the time when the blos- 

 soms show pink, just before the petals begin to open, using, as 

 a rule, the 6-4-50 strength. In order to obtain the best results from 

 Bordeaux, it is essential that the mixture should be properly made. 

 This is to insure, through using the proper proportions and by careful 

 mixing- to facilitate, the necessary chemical changes between the blue- 

 stone and the lime, the proditction of a fungicide which, Avhile capable 

 of destroying the spores of the fungus, will not injure either the foliage 

 or the fruit. The 6-4-50 formula, which consists of 6 lbs. sulphate of 

 copper (bluostone), 4 lbs. of calcium oxide (quicklime), and 50 gallons 

 water, is now practically regarded as a standard, it being necessary only 

 to reduce or increase the quantity of Avater to obtain a stronger or 

 weaker mixture. 



In preparing Bordeaux mixture in small orchards, three barrels — t:ao 

 of 25 gallons capacity each and one of 50 gallons — are required, but 

 vessels for use in large plantations may be Avhatever size is necessai'y, 

 but they should be of like proportions to each other. To prepare the 

 mixture from the above formula, nearly fill one of the 25-gallon barrels 

 Avith fresh water, then place the 6 lbs. of bluestone in an old sugar-bag, 

 and suspend the same just beloAv the surface. Bluestone is easily soluble 

 in cold Avater, but it will dissoh^e much more rapidly if the water be first 

 heated. Then slake 4 lbs. fresh lime in a bucket, applying the Avater 

 sloAvly at first, and, when the solution is in a fit condition, carefully 

 strain >ame olf into the other 25-gallon barrel and add sufficient Avater 

 to fill the container. When quite cool, both the bluestone and milk of 

 lime solution, after each has been thoroughly stirred, should be poured 

 evenly from ^tAv^o taps fixed near the bottoms of the barrels, through a 

 strainer into the 50-gallon receptacle, or into the spraying vat. During 

 this time, and Avhile the spray is being applied to the trees, the mixtui'e 

 should be kept Avell agitated. Fortunately, since the introduction of 

 motor spray pumps, which are fitted Avith jioAverfnl agitators, this 

 condition of the mixture is easilv maintained. 



