February, '10] COOLEY : OYSTER SHELL SCALE 61 



tory treatment. Ven* distinct, though not extensive injury to the 

 foliage. 



15. Pratt's ' ' Scalecide " at rate of one to seventy-five. Same re- 

 sults as with No. 14. but with less injury to the foliage. 



16. Linseed oil emulsion, prepared as for test No. 1. 



Raw linseed oil 1 gal. 



Hard soap 1 ib. 



Water to make 12 gal. 



Practically all the lice were killed, and the treatment was consid- 

 ered very satisfactory. This and the cottonseed oil emulsion treat- 

 ments were considered to be the most satisfactory for summer use. 

 The trees were not injured. 



In connection with judging the results of this treatment we should 

 mention that the Board of Horticulture sprayed a neighboring orchard 

 with linseed oil emulsion, independent of the writer's experiments, 

 on June 24 and 25. The scales were all killed and a small amount of 

 injury was done to the foliage. Other trees were sprayed by the 

 board with cottonseed oil emulsion, resulting in a killing of all the 

 young scales, with less injury to the foliage. 



17. Cottonseed oil emulsion. Prepared as with linseed oil emul- 

 sion. 



Cotton seed oil 1 gal. 



Hard soap 1 lb. 



Water to make 12 gal. 



Results were practically the same as with linseed oil emulsion sum- 

 mer spray. No injury to foliage. 



18. Kerosene emulsion, one part stock emulsion to twelve of water. 

 Very few, if any, of the scales were killed. 



19. Whale-oil soap solution at rate of one pound to eight gallons 

 of water, applied warm. A few, possibly 10 to 15 per cent, were 

 killed. 



20. "Rex" lime-sulfur solution, one part to fifteen of water. The 

 treatment was unsatisfactory, very few young being killed. 



21. " Self -boiled " lime-i?ulfur solution. Practically no good was 

 done. 



Lime 15 lbs. 



Sulfur 10 lbs. 



Water 50 gal. 



