696 Bulletin 83. 



that in May the fast maturing females are not susceptible to the 

 emulsion unless it is used so strong as to injure the foliage. The 

 eggs are also safe under their mother's shell during June. 



However, the newly-hatched scales which emerge about July i, 

 can be easily killed with the emulsion diluted even 6 or 8 times. 

 But the application must be made while the scales are moving 

 about on the branches ; for if they once get established on the 

 leaves, it will be impracticable to hit a majority of them. By 

 tipping over some of the scales every day or two during the lat- 

 ter part of June, one can tell with a lens when a majority of the 

 scales have emerged. When they have done so, do not wait a 

 moment, but completely drench the trees with the emulsion diluted 

 6 or 8 times. We visited an orchard in July after the scales had 

 become established on the leaves. Nearly every leaf bore hun- 

 dreds of the little creatures, but it was evident that man was 

 powerless so far as checking them with a spray was concerned. 

 It would have been necessary to literally drench the undersides 

 of every leaf, an impracticable task with a spray. Nothing but 

 the expensive gas treatment with tents, so commonly used in 

 California, would have been of any practicable use. Thus, the 

 pest cannot be effectively and practicably checked by sprays while 

 it is on the leaves from July i until the leaves fall in October. 

 Unless the expensive gas treatment can then be resorted to, fruit 

 growers will be obliged to stand idly by in the summer and see 

 the pest do its most damaging work. 



Fortunatel3^ however, the scales grow but little during the 

 summer, and then migrate to the branches where they go into 

 hibernation in a tender stage. Therefore, after the leaves fall in 

 autumn, af&icted fruit growers may begin the work of extermina- 

 tion. The little tender scales are then exposed on the undersides 

 of the branches and in crevices all over the tree. There are then 

 no leaves to bother, and every scale that is hit with the emulsion 

 dituted 4 times, speedily dies. Do not expect to see the scales 

 drop off immediately, or even for several days after spraying. It 

 is difl&cult to tell a dead scale from a live one. If the branches 

 are brought into a warm room and the scales examined closely 

 with a lens after a few days, life can be detected in the uninjured 

 scales. Dead scales are usually of a distinctly lighter brown 

 color and are somewhat shriveled in appearance ; where large 



