New York Agricultural Experiment Station. 97 
On June 18, an examination was made of all the plants in four rows 
of the plat, fifty-five in number, with the following results: 
Twenty-nine treated plants were attacked by 124 maggots. 
Twenty-six not treated were attacked by 25 maggots. 
One of the treated rows was on the outside of the plat, and it was 
observed that the plants in the outside rows, and at the ends of the 
inside rows were more infested than the others. The greater number 
of maggots found in the treated rows is to be ascribed to this fact, 
and not to an assumption that the nitrate of potash attracted, the 
cabbage fly. 
The last application was made but two days before the examination, 
but many live larvse, that had apparently just hatched, were found in 
the treated rows, thus showing that the solution was harmless to the 
insects. As an additional test, a cabbage plant badly infested with 
maggots was placed in a flower-pot, and treated repeatedly with a 
saturated solution of the salt, but no effect upon the insects was 
observable. 
Air-Slacked Lime for the Cabbage Maggot. 
It has been claimed that lime placed about the roots of young cab- 
bage plants will prevent injury from this insect. As an experiment, a 
quantity of air-slacked lime was mixed with the soil of two rows of a 
small plat of early cabbages at the time of setting the plants. As the 
season for the attack arrived it appeared that the plants of the plat 
were all suffering, and an examination made June 18, showed that 
twelve plants treated with the lime had sixty-six maggots, while eleven 
plants not treated had but twenty-four maggots, proving conclusively 
the ineffectiveness of the application. 
Applications for the Larv^ of the Potato Beetle. 
1. Paris green. 
In previous years we have sought to determine the minimum 
amount of Paris green, mixed with land plaster, that proves effective 
in destroying the larvse of the potato beetle, Doryphora 10-lineata, Say. 
Several experiments indicated that one part of the poison to 150 of 
the plaster is sufficient when the two are thoroughly mixed. 
Some potato growers, however, prefer to use water as a diluent for 
the poison. For the benefit of such, the attempt was made to discover 
the minimum amount of the latter that proves effective when used in 
this way. 
One-fourth of an ounce of Paris green, mixed with five gallons of 
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