THE GEEEX JUNE BEETLE. 41 



therefore, that the results obtained did not fully substantiate expec- 

 tations. Even at that stage of growth and at the depth mentioned, 

 however, the liquid penetrated to the larvae, and several grubs were 

 found to have come to the surface, turned yellow, and perished. It 

 is evident, as a result of these tests, that the success of kerosene 

 emulsion as an insecticide where growing crops are concerned is 

 dependent upon the stage of growth of the larva? and the depth at 

 which the grubs happen to be at the time of application. When 

 they are young and -work relatively near to the surface kerosene 

 emulsion will prove more efficacious than when they are older and 

 farther below the surface. In cold frames particularly, and in other 

 instances where the grubs are known to be present and other methods 

 of control suggested do not seem feasible, kerosene emulsion should 

 be applied at the rate mentioned and be followed by a copious water- 

 ing from a garden hose or sprinkler unless there are heavy rains. 



EXPERIMENTS CONDUCTED ELSEWHERE WITH KEEOSENE EMULSION. 



Five additional experiments were conducted with kerosene emul- 

 sion with variable results. At Eosslyn, Va., an imperfect emulsion 

 was made on golf links by using a barrel and a half of kerosene 

 mixed with water and passing the oil and soap from one tub to 

 another until an emulsion was supposed to be produced. This killed 

 all the white grubs, but it also destroyed the grass. Still the ex- 

 perimenter was perfectly satisfied with the result. Other corre- 

 spondents had the same experience, as usual not making a perfect 

 emulsion. A correspondent at Saltville, Va., experimented with a 

 combination of kerosene oil and castile soap, according to directions, 

 but since an egg-beater was used in agitating the mixture, it was 

 not properly mixed. It was applied on the plants with an ordinary 

 water sprinkler, the grubs were killed, but about 75 per cent of the 

 strawberry plants were injured. 



Another experiment was made with the same imperfect emulsion 

 which was poured about the plants. It killed the grubs without 

 injuring the plants, as the leaves did not come in contact with it. 



In experiments performed by Mr. Davis at Louisville, Ky.. on 

 golf links 80 per cent of the grubs in the treated area were killed 

 by a single application of kerosene emulsion made at the rate of 

 rabout 1 gallon to 6 or 8 square feet and afterwards thoroughly washed 

 onto the soil by copious sprinkling with water, a remedy which the 

 Bureau of Entomology has recommended for many years for white 

 grubs and similar forms of insects. An important point in the ap- 

 plication of this insecticide is that it should be made as soon as 

 the grubs become conspicuous, usually about the middle of Septem- 

 ber, or at about the time when they begin to crawl about on the sur- 

 face of the ground.. 



