[15] Report of the State Entomologist. 157 



strong briue to kill the worms — so strong as to kill the bush also 

 unless it be washed off at once by a good wetting with pure water, 

 when no harm is done to the foliage. 



This method, if effectual, would be desirable for use against the 

 second brood of worms that makes its appearance in July, if there is 

 fear that the fruit might be dangerous for use from the application of 

 hellebore. 



Saltpetre not a Preventive of Cabbage-fly Attack. 



In the Second Bejwrt on the Insects of New York, 1885, page 28, in 

 consideration of statements quoted from agricultui-al journals of the 

 complete efficacy of a solution of saltpetre in protecting from cut- 

 worms and insects attacking squash and cucumber vines, it was 

 recommended that experiments with this solution be made upon our 

 smaller root insects, such as the radish, cabbage and onion maggots. 



At my request, Mr. E. S. Goff, of the N. Y. Agricultural Experiment 

 Station, has kindly made exj^eriments with it upon the most injurious 

 of the above insects, viz., the cabbage-maggot, with the following 

 results: 



I dissolved one pound of saltpetre in two gallons of water and 

 poured about a gill of the solution around each plant, leaving alter- 

 nate rows untreated. This was done on the first indication that the 

 plants were infested, which was on May thirty-first. The application 

 was repeated on June fourth, tenth and sixteenth. On June eigh- 

 teenth, twenty-nine of the treated plants and twenty-six of those not 

 treated were examined. On the former 124 maggots were found, and 

 on the latter twenty-five. The treated row was the outside of the plat, 

 which may account for its having been infested more than the others. 

 I have frequently noticed that outside rows are more injured by inju- 

 rious insects than the others. The experiment proved conclusively that 

 nitrate of potash used in the strength and manner described, is not 

 destructive of the maggot, as I repeatedly found the young, appar- 

 ently just hatched, on the treated plants, as well as of all other stages 

 of development. 



In order to see if a stronger solution would avail, solutions of vary- 

 ing degrees of strength were tried, uj) to saturation, but the larvse 

 were able to endure the strongest. 



We also tried the effect of mixing aii'-slacked lime with the soil at 

 the time of setting the plants, but with no better success. 



In view of the above experiments, it is not probable that the value 

 of the saltpetre solution as a preventive of cut-worm injur3% would be 

 sustained by experiments as carefully conducted as were those of 

 Mr. Goff. Its insecticidal properties, if it possesses any, have 

 evidently been overstated. 



