58 NEW YORK STATE MUSEUM 



are added 4 to 6 pounds of soap, the latter being particularly valu- 

 able because it increases the spreading properties of the insecticide, 

 or the tobacco may be added to the standard lime-sulphur wash, 

 in which event soap is an undesirable addition. The most effective 

 spraying is that given just before the buds have opened, because 

 this means the destruction of the pest prior to its causing any material 

 damage. The next best opportunity is just as the blossom buds 

 have pulled apart and thus reduced the shelters of this insect to a 

 minimum. A third treatment, if necessary, can be applied later 

 after the leaves have partly expanded. This is directed largely 

 against the young. 



Experimental work. Owing to the very short time during which 

 the above treatments can be made to advantage, there have been 

 numerous failures in controlling the pest, which have resulted in 

 experiments with a thick lime-sulphur wash composed of approxi- 

 mately 150 pounds of lump l,ime, 20 gallons of a standard lime- 

 sulphur wash to 200 gallons of spray. This, in other words, is the 

 usual lime-sulphur -wash employed against San Jose scale, to which 

 a considerable excess of lime has been added. There are practical 

 difficulties in the preparation of this wash, owing to the large amount 

 of lime used. One method of preparing is to slake, in a barrel, 

 75 pounds of good stone lime, starting with five or six pails and 

 keeping the lime covered so as to prevent it from burning. Dilute 

 as much as practical while still in the barrel and then strain 

 through an ordinary mosquito wire netting. This latter is made 

 easier by diluting the lime wash considerably, taking care not to 

 exceed the ultimate proportions, and by starting the engine and 

 using one spray nozzle to wash the somewhat glutinous lime through 

 the screen. A very coarse grain sack can be used in place of the 

 wire screen and lessens the probability of clogging the strainer on 

 the suction hose. This latter should be large and accessible so 

 that the pasty lime-sulphur compound can be' easily and quickly 

 removed. 



Lime-sulphur wash prepared as above was applied April 19th to 

 a young pear orchard belonging to C. H. Deuell & Son of Bangall. 

 About fifty small pear trees, mostly Seckles, were thoroughly sprayed 

 with 200 gallons of the insecticide. One man stood upon the spraying 

 rig, the other working from the ground, and an attempt was made 

 to cover all portions of each tree at one treatment. It was found 

 in practice, however, that one corner of a tree or the under side of 

 branches here and there were apt to be partly skipped, and a second 

 application was made for the purpose of covering the trees thoroughly . 



