FORTIETH ANNUAL REPORT. 177 



age, fruit, and buds are also essential in making the second application, 

 as the beetles are still very numerous, feeding and ovipositing freely. 

 (See Table II.) This is also the most important application for the pre- 

 vention of scab infection, which is prevented only by thoroughly coating 

 the young fruits. In subsequent applications the efforts should be di- 

 rected more to coating the fruit with the spray to protect it from brown- 

 rot infection, especially as it begins to ripen. 



The schedule of applications takes account of the ripening period 

 of the principal commercial varieties of peaches. Applications made 

 later than a month or six weeks before picking time are likely to result 

 in the fruit being more or less spotted with the spray when harvested, 

 somewhat marring its appearance for market purposes. This danger 

 can be largely avoided by using nozzles which throw a mist-like spray, 

 coating the fruit with very fine dots rather than with large blotches. 



DIRECTIONS FOR THE PREPARATION OF SELF-BOILED LIME-SULPHUR WASH. 



The standard self-boiled lime-sulphur mixture is composed of 8 pounds 

 of fresh stone lime and 8 pounds of sulphur to 50 gallons of water. In 

 mild cases of brown-rot and scab a weaker mixture containing 6 pounds 

 of each ingredient to 50 gallons of water may be used with satisfactory 

 resiults. The materials cost so little, however, that one should not 

 economize in this direction where a valuable fruit crop is at stake. Any 

 finely powdered sulphur (flo'wers, flour, or "commercial ground" sul- 

 phur) may be used in the preparation of the mixture. 



In order to secure the best action from the lime, the mixture should 

 be prepared in rather large quantities, at least enough for 200 gallons 

 of spray, using 32 pounds of lime and 32 pounds of sulphur. The lime 

 should be placed in a barrel and enough Avater (about 6 gallons) poured 

 on to almost cover it. As soon as the lime begins to slake the sulphur 

 should be added, after first running it through a sieve to break up the 

 lumps, if any are present. The mixture should be constantly stirred and 

 more water (3 or 4 gallons) added as needed to form at first a thick paste 

 and then gradually a thin paste. The lime will supply enough heat to 

 boil the mixture several minutes. As soon as it is well slaked water 

 should be added to cool the mixture and prevent further cooking. It 

 is then ready to be strained into the spray tank, diluted and applied. 



The stage at which cold water should iDe poured on to stop the cook- 

 ing varies with different limes. Some limes are so sluggish in slaking 

 that it isi difficult to obtain enough heat from them to cook the mixture 

 at all, while other limes become intensely hot on slaking, and care must 

 be taken not to allow the boiling to proceed too far. If the mixture is 

 allowed to remain hot for 15 or 20 minutes after the slaking is com- 

 pleted, the sulphur gradually goes into solution, combining with the lime 

 to form sulphids, which are injurious to peach foliage. It is therefore 

 very important, especially with hot lime, to cool the mixture quickly by 

 adding a few buckets of water as soon as the lumps of lime have slaked 

 down. The intense heat, violent boiling, and constant stirring result in 

 a uniform mixture of finely divided sulphur and lime, with only a very 

 small percentage of the sulphur in solution. It should be strained to 

 take out the coarse particles of lime, but the sulphur should be carefully 

 worked through the strainer. 

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