THE WESTERN CABBAGE FLEA-BEETLE. 15 



Experiment No. 1. — -August 19, 1911. 



Nicotine sulphate, paste ounces. . 3 



Fish-oil soap do. ... 8 



Water gallons. . 10 



It was noted that when the beetles were thoroughly wet with 

 this spray they appeared to be soon killed. Later experiments, 

 however, demonstrated that the beetles afterward came to life. 

 Nevertheless, the single application showed considerable ralue, and 

 if additional applications had been made to the same planting, the 

 efficiency of this deterrent could have been demonstrated. Naturally 

 no harm was done to the plants. 



Experiment No. 2. — June 3, 1911. 



Arsenate of lead was used with an equal amount of soap at the rate of about 6 pounds 

 to 50 gallons of water, on radish, cabbage, and mustard, but as only one application 

 was made the plants became reinfested. 



Experiment No. 3. — June 22, 1911. 



Arsenate of lead, paste pounds. . 6 



Soap, common laundry. do 6 



Water gallons. . 50 



In this experiment young cabbage was sprayed on both the upper 

 and lower surfaces and the plants were heavily coated, almost white- 

 washed, the spray adhering well. This had the effect of deterring 

 most of the beetles and although no dead ones could be found it was 

 evident that the spray acted as a powerful repellent. 



Experiment No. A- — July .22, 1911. 



Arsenate of lead, paste pound. . 1 



Whale-oil soap do 1 



Water gallons. .. 10 



This was applied to radish and cabbage, the leaves of the latter 

 being badly pitted. Every portion of the plants was wet on both 

 the upper and lower surfaces. As in the previous experiments no dead 

 beetles could be found and, although rainfall washed away much of the 

 arsenate, in four days the plants had improved wonderfully and 

 made excellent growth. As the rain left the plants practically unpro- 

 tected a second spraying was made of the same mixture two days 

 later. Nine days afterwards the cabbage was in excellent condition 

 and practically free from insect pests, only an occasional beetle being 

 found. 



Experiment No. 5. — September 5, 1911. 



Nicotine sulphate, paste ounces. . 4 



Whale-oil soap do 8 



Water gallons. . 10 



After the application of this spray it was noted that the beetles 

 which came in contact with the treated leaves jumped wildly and 

 and after a brief struggle apparently died, but revived within half an 

 hour. The plants showed no injury from the spraying. 



