New York Agricultural Experiment Station. 411 



Table II. — Effect of Carbolic Acid on Maggots Under Soil Conditions. 



Strengths of emulsions in 

 carbolic acid. 



Number 



of larvae 



in test. 



Number 

 killed. 



Number 



alive 



after 



treatment. 



0.22 per ct 

 0.26 per ct 

 0.33 per ct 



5 

 5 



5 





 1 



2 



5 



4 

 3 



Results of tests with carbolic-acid emulsion on larva. — These tests 

 show that immersion in carbolic-acid emulsion containing 0.33 

 per ct. is fatal to the larvae of the second instar, and that the smaller 

 individuals of the third instar are to a large degree susceptible to 

 treatment, while the large maggots of this same stage are immune. 



Field experiments with carbolic-acid emulsion. — During the spring 

 of 1906 a cabbage seed-bed was treated with carbolic-acid emulsion 

 by Mr. L. A. Page of Seneca Castle, in cooperation with the Station. 

 The soil about the roots was thoroughly saturated by gently pumping 

 the mixture through a spray hose with the nozzle removed. The 

 maggots were numerous about the roots of the plants and had 

 caused serious injury before they were discovered. Apparently 

 the work of tke insects was not checked by the emulsion, for the 

 seed-bed was so completely destroyed that no plants were available 

 for transplanting. A similar experiment with this mixture was 

 performed in 1908 on the same farm. The application was made 

 to a seed-bed in anticipation of an attack by the insect. The maggots 

 were few in number, and following the application no differences 

 were observed in the treated and untreated plats. It should be 

 noted that the emulsion was not harmful to the young seedlings 

 which at the time of treatment were from five to seven inches high. 

 In another experiment in an adjoining seed-bed during the same 

 season the emulsion proved very destructive when applied to young 

 seedlings one to two inches high. 



During 1913 the emulsion was used at a dilution of 0.37 per ct. 

 carbolic acid in two commercial plantings of early cabbage. The 

 soil in one field was a heavy clay while in the other it was a light 

 sand. In both of the tests the emulsion caused serious injury to 



