8 BULLEtfTIK. Ijfiify Ttf..g,.DEPAR^ENT OF AGRICULTURE. 



Coal-tar emulsion (prepared by'Ynsectictde Board); 1 part emulsion to 10 

 parts water. Pine logs dipped and sprayed were attacked after 15 days by 

 insects of type 4 and later by those of all types. Final results were^ no better 

 than in the case of the controls. 



Crude petroleum. Pine logs sprayed and dipped with crude petroleum were 

 attacked by insects of type 4 after 15 days and later by those of all types. 

 Final results were no better than with the controls. 



Anthracene oil emulsio-n (prepared by Insecticide Board); 1 part emul- 

 sion to 10 parts water and 1 part emulsion to 100 parts water. Dipped pine 

 logs were attacked by insects of type 4 after 15 days and later by those of all 

 types. The final results were no better than with the controls. 



Crude solvent naphtha. Pine logs dipped with this material were slightly 

 attacked by insects of type 4 after 15 days and later by all types. Final 

 results were but little better than with the controls. 



Six ounces of nitrobenzene in one gallon of kerosene. Pine logs sprayed 

 and dipped were attacked after 15 days by a few insects of type 4 and later 

 by more of the same type. The final results were somewhat better than with 

 the controls. 



Fish oil. Pine logs sprayed and dipped were immediately attacked by 

 insects of type 4 and later by all types. Final results were no better than 

 with the controls. 



Two parts fish oil, one part pine oil, and three parts kerosene. Pine logs 

 sprayed and dipped were attacked after 15 days by insects of type 4 and later 

 by all types. The final results were no better than with the controls. 



Kerosene. Pine logs sprayed and dipped were attacked after 15 days by 

 insects of type 4 and later by all types; results were no better than with the 

 controls. 



Sulphite concentrate (furnished by a paper-pulp null) ; full strength an,d 

 diluted with equal parts of water. Pine logs dipped were attacked after one 

 week by insects of type 4 and later by all types. Final results were no better 

 than with the controls. 



Spent sulphite; full strength and equal parts spent sulphite and, a commercial 

 miscible oil. The results in pine logs dipped and sprayed were the same as 

 with sulphite concentrate. 



Tree ffum (furnished by Gipsy Moth Laboratory) ; 1 pound of tree gum 

 dissolved in 1 quart of turpentine. Pine logs treated with a brush were at- 

 tacked by a few insects of type 4 after two months. The results were much 

 better than on the controls, but the material held moisture in the log and pro- 

 duced much bluing of sap when insects penetrated the bark. The sticky film 

 acted as a mechanical barrier. 



One pound of melted paraffin with one gallon of gasoline added. Pine, ash, 

 and juniper logs were sprayed and clipped and placed in a cage for experiment 

 against insects of type 4. This treatment prevented all attack on the more 

 absorbent bark of ash and juniper. A few insects attacked the pine. 



One-half pound of naphthalene dissolved in one gallon of gasoline. Dipped 

 pine logs were attacked after 15 days by insects of type 4 and later by all. Final 

 results were but little better than with the controls. The naphthalene soon 

 evaporates and no odor is left. 



One pound of melted paraffin with one-half pound of naphthalene and one 

 gallon of gasoline added. Pine, ash, and juniper sprayed and dipped and 

 placed in a cage against type 4 were attacked by insects of this type after 30 

 days. 



