192 FARM CROPS 



stances, a longer period is allowed. During what 

 may be termed an epidemic of blight, it may be 

 necessary to spray every seven days. Light appli- 

 cations and frequent are more effective than heavy 

 applications and less frequent. 



To prepare bordeaux, slake 4 pounds of good, 

 fresh quicklime in 10 gallons of water. Dissolve 5 

 pounds of copper sulphate, that is, blue vitriol, 

 sometimes called bluestone, also, in 10 gallons of 

 water, preferably hot, to hasten the dissolving 

 process. If the copper sulphate is suspended near 

 the top of the water in a sack, the results will be 

 more satisfactory. When the mixture is wanted, 

 pour the two solutions thus obtained slowly into a 

 barrel containing 30 gallons of water, vigorously 

 stirring during the pouring process. The mixture 

 will soon lose strength, hence the necessity for using 

 it fresh. If flea or potato beetles are giving trouble, 

 about I ounce of paris green of good quality should 

 be added to each 10 gallons of the mixture. 



On small areas compressed air sprayers which 

 hold not more than 5 gallons of the mixture may 

 be used. For larger areas knapsack sprayers will 

 answer. For still larger areas a barrel spray pump 

 mounted on a light wagon or two-wheeled cart, 

 drawn by one horse, may be necessary. When in 

 use, one man rides, drives and pumps, and two men 

 walk and spray. The pump has two leads of hose, 

 each about 15 feet long, and provided with double 

 nozzles. Several rows are thus sprayed at one time. 

 For still larger fields, geared pumps operated by 

 horse power have been found entirely practical. 

 Two or three hours should elapse after spraying 

 before rain falls. It is a matter of prime importance 

 that the vines shall be well covered with the 



