40 BULLETIN 891, U. S. DEPARTMENT OF AGRICULTURE. 



may be effective on a small scale it is scarcely applicable for large 

 areas. It has been pronounced the most direct remedy or insecticide 

 employed experimentally by the cereal and forage crop insect spe- 

 cialists. 



Since the burrows of this grub are open they are easily reached by 

 the fumigant, the poisonous fumes of which are heavier than air. 

 Carbon disulphid is injurious to grass and to plant life generally 

 when applied direct and it is therefore recommended that a funnel 

 be inserted into the holes made by the larvse and beetles before pour- 

 ing in the required amount of liquid disulphid, in this case about a 

 teaspoonful to each opening. A large copper engine oiler forms an 

 efficient injector for this purpose. 



Caution. — Care should be exercised in the handling and use of 

 carbon disulphid, since it is highly inflammable and the fumes, when 

 mixed with a certain proportion of air, are explosive. There should 

 be no fire of any kind, such as a cigar, near by when handling the 

 liquid. 



Kerosene Emulsion. 



Kerosene emulsion was tested in 1888 by Mr. W. B. Alwood (14), 

 when engaged in the Bureau of Entomology, on the Capitol grounds 

 at Washington, D. C., where the grubs occurred abundantly on lawns. 

 Application at the rate of 1 part of the standard mixture to 15 parts 

 of water was made, and for several days afterwards the ground was 

 kept freely soaked with water, with the result that not a single 

 larva was found while the check plat adjoining contained numerous 

 larvae, only a few of which were dead. 



Writing in 1901, Dr. L. O. Howard (32) stated that in experi- 

 ments by Mr. Lull, formerly of the Bureau of Entomology, kerosene 

 emulsion proved effective against such grubs as happened to be 

 near the surface, but failed to reach those which were lower. Ex- 

 periments with kerosene emulsion against the grubs of C. nitida 

 conducted by others tally with the above observation. 



TESTS WITH KEROSENE EMULSION. 



Several experiments were conducted in the vicinity of Portsmouth, 

 Va., with kerosene emulsion applied at the rate of 1 to 5 and 1 to 10 

 to cold-frame sash-growing parsley, using from 1 to 4 gallons of the 

 liquid per sash. Tests were also conducted in the field, and in 

 both instances the liquid was poured into the perforations made by the 

 grubs, which extended from the surface of the soil to 6 to 10 inches 

 below. At the time these tests Avere made the grubs were from one- 

 half to three-fourths grown, and weather conditions were such that 

 thej worked at the depth mentioned above. It was not surprising. 



