THE CABBAGE MAGGOT 



11 



calomel were relatively ineffective, especially against hea\^ infestations, although 

 they showed 50 to 60 percent less injury than was suffered by untreated plants. 



Table 6. Control of Cabbage Maggot and Effect on Growth of Head 



Obtained from Applications of Calomel Insecticides to Stem and Roots 



OF Cabbage at Transplanting. VValtham, Massachusetts. 



Percent of 



Calomel in 



Powder 



Carrier 



1938 



1940 Average 



Percent of Commercially Uninjured Plants 



89.33 97.33 



98.0 97.98 



97.99 



100.0 



54.0 



86.0 



94.0 



92.0 



76.0 



82.0 

 1.0 



90.67 93.33 



86.67 90.00 



60.67 82.43 



64.0 61.07 



100.0 99.33 



22.67 12.66 



78.7 

 88.0 



68.0 

 77.3 



86.67 

 78.67 



65.96 

 71.98 

 70.65 



82.67 57.29 



90.00 79.95 



76.67 80.60 



72.67 78.59 



100.0 

 32.0 



57.3 



68.0 

 78.6 



71.90 

 81.30 



83.33 

 62.0 



93.25 

 27.33 



72.0 

 52.87 



93.33 



97.99 



88.50 



62.0 



87.57 



88.00 



61.00 



88.33 



68.0 



77.3 



73.0 



54.0 



71.55 



56.0 



62.53 



40.0 



97.56 



14.72 



100 None 88.0 92.0 



75 Talc (fibrous) 



50 Gypsum 79.0 



50 Clay (Bancroft) 60.0 64.0 



50 Talc (fibrous) 



50 Talc (amorphous) 



25 Clay (Bancroft) 42.0 80.0 



25 Talc (fibrous) 



25 Talc (fibrous) 



25 Talc (amorphous) 



20 Gypsum 73.0 



10 Clay (Bancroft) 



10 Talc (fibrous) 



8 Gypsum 56.0 



5 Talc (fibrous) 



4 Gypsum 40.0 



Check (Standard Treatment '). . 100.0 88.0 98.0 100.0 99.33 

 Check (Untreated) 40.0 12.0 



Percent of Large and Medium Heads 



100 None 82.0 



75 Talc (fibrous) 



50 Gypsum 63.83 



50 Clay (Bancroft) 40.0 



50 Talc (fibrous) 



50 Talc (amorphous) ' 



25 Clay (Bancroft) 50.0 



25 Talc (fibrous) 



25 Talc (fibrous) 



25 Talc (amorphous) 



20 Gypsum 56.99 



10 Clay (Bancroft) 



10 Talc (fibrous) 



8 Gypsum 19.0 



5 Talc (fibrous) 



4 Gypsum 3.0 



Check (Standard Treatment*) . . 87.75 70.0 



Check (Untreated) 5.34 13.0 



♦Corrosive Sublimate 1-1280, two applications at weekly intervals beginning when the first 

 eggs are laid. 



75.59 

 75.33 

 67.24 

 67.00 

 69.32 

 78.6 

 71.00 

 84.98 

 71.90 

 81.30 

 56.99 

 76.0 

 78.63 

 19.0 

 75.63 

 3.0 

 89.72 

 26.92 



