The Pernicious Scale Insect in New Hampshire. 275 



three applications of Bordeaux, the use of a knapsack sprayer may be found ad- 

 visable. After the vines have become grown, a barrel pump, two lines of hose, 

 and double Vermorel nozzles are necessary to do thorough work. It may be 

 found convenient to leave every -sixth or seventh row vacant when planting, to 

 make a roadway for tlie spraying apparatus during the season. This may lie 

 done to suit the convenience of tlie grower, but liowever the spraying is man- 

 aged, thorough work must be done in order to secure f.ood results. Weather 

 conditions may have something to do with determining the number of applications, 

 but in any case a thorough spraying should be given the plants at least once 

 in two weeks, as long as tliere is danger from blight. 



BOKDEAT'X MIXTURE— rROPEK WAY OF MAKIXCx. 



Preparation of this mixture has a great deal to do with its ease of applica- 

 tion and its efficiency. The wrong way to make Bordeaux mixture is to pour 

 a strong solution of copper sulphate dissolved in water into a strong solution 

 of milk of lime, and subsequently adding sufficient water to make up the desired 

 formula. The action of tlie copper sulphate and lime when mixed in a concen- 

 trated form is such that a heavy precipitate is formed, which r.-ipidly settles to 

 the bottom, leaving clear water on top. The right way to make Bordeaux mixture 

 is to dilute both the copper sulphate and lime solution with the full amount of 

 water before being mixed. Two samples of the mixture, containing the same 

 ingredients, but mixed in the different ways noted, if placed in jars side by side 

 will show the difCerence. At the end of the five hours the one containing the 

 wrongly compounded mixture will show a heavy white precipitate at the bottom, 

 while the jar witli the properly made mixture will hardly commence settling. The 

 precipitate of the compound of lime and copper sulphate is held in suspension in 

 the water, and the length of time before the precipitate settles to the bottom 

 indicates the fineness of the precipitate. To do the best work with Bordeaux 

 mixture a fine spray must be obtained. To obtain this the precipitate of the 

 mixture must be fine, or a small aperture nozzle or fine strainer can not be used 

 without trouble from clogging : hence the importance of proper preperation of 

 the mixture. 



Another important detail in the use of Bordeaux mixture is the testing 

 before using, to make sure that the mixture is not acid. Much trouble is fre- 

 quently experienced from the burning of foliage because of the acidity of the 

 mixture. This can be easily avoided. A few cents" worth of ferrocyanide of 

 jiotassium dissolved in water makes a sure test, that is easily applied. After the 

 Bordeaux mixture is made and thoroughly stirred up, dip out a small amount in 

 a cup. To this add a few drops of the test solution. If the mixture is acid, a 

 dark brown coloration will immediately appear. In that case add more lime 

 water till no coloration comes from the addition of the test solution. 



Iti all cases Bordeaux mixture should be used within a few hours after being 

 made, as it rapidly deteriorates in value from standing. 



THE PERNICIOUS SCALE INSECT IN NEW HAMPSHIRE. 



By Clakence M. Weed, New Hampshire College Agricultural Experiment Station. 



The San Jose or pernicious scale has attracted more attention from Ameri- 

 can fruitgrowers during the last ten years than any other insect It has 

 been recognized as a most dangerous pest which was likely to be introduced 

 Into any community through the sale of young trees. It was apparently first 

 introduced into New Hampshire at Manchester about ten years ago, but it has 



