New York Agricultural Experiment Station. 499 



larger proportion of the plants in fields generally grew slowly, 

 forming small heads, which frequently were not of standard 

 size for the market. During August the odor of decaying cabbage 

 was very perceptible in fields in the region of Geneva. 



DIRECTIONS FOR SPRAYING. 



Spraying Mixtures. 



Formula 1, Soap. 



Soap 6 to 8 lbs. 



Water 50 gals. 



Formula 2, Nicotine Extract. 



Nicotine extract 40 per ct. ( Black Leaf 40 ) % pt. 



Water 100 gals. 



Soap 3 to 5 lbs. 



Applications of one of the above formulas should be made as 

 soon as the lice appear in threatening numbers and before any 

 of the leaves are appreciably curled. The liquid should be applied 

 under reasonably high pressures, and directed especially into the 

 heart and to the undersides of the leaves of the cabbage, where 

 the lice are usually assembled in greatest numbers. The quantity 

 of mixture to apply and the number of applications required to 

 afford efficient protection depend largely on the extent of infestation 

 and seasonal conditions, as these may influence the duration of the 

 period in which the lice continue to breed in destructive numbers. 

 In plantings that were well infested with lice there was required in 

 the Station tests from 150 to 175 gallons of spraying mixture per 

 acre for one treatment, and during 1913, when reproduction of the 

 aphis continued over a long period, two sprayings gave very effi- 

 cient results, although the most profitable returns were obtained 

 by three treatments at intervals of ten to fourteen days. In the 

 employment of Formula 2, nicotine extract, which is the more 

 costly of the above mixtures, the expense should not exceed $2.30 

 for the spray material and $2.40 for labor and team at liberal 

 estimates, which make a maximum cost of $4.70 per acre for one 

 spraying. In cooperative efforts with cabbage-growers in spraying 

 under farm conditions the most successful experiment was con- 

 ducted at a cost of $4.10 per acre for a single treatment, which 

 was all that was required to protect one field of cabbage under the 



