240 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 12 



attacked the plants listed below, besides many of those given above: 

 English peas, eggplant, blackberry, cantaloupe, carrot, onion, peanut, 

 potato, watermelon; and the following flowering plants: candytuft, 

 chrysanthemum, cockscomb, columbine, cornflower, larkspur, marigold, 

 petunia, pinks, poppy, rose, snapdragon, spearmint, sweet pea, verbena 

 and zinnia. 



Experiments with Control Measures. — When the comf)laints 

 first began coming in we recommended the use of light traps. The 

 lights were placed over vessels buried with the tops level with the sur- 

 face of the ground, some dry and others containing water. Only a 

 few of the beetles were caught by this method. 



We also recommended hand-picking. This method has been used 

 by many people in former outbreaks and is effective where only a few 

 of the beetles can migrate into the garden. But it proved to be a 

 tedious and useless remedy for a small garden surrounded by large 

 lawns and vacant lands or other gardens from which the pest could 

 migrate. 



The use of bran mash or the application of arsenicals to the plants in 

 powder form or liquid spray would be effective in large market gardens 

 but could not be recommended for use in small gardens because poultry 

 would often have access to the poison or the dead beetles. 



We know of one man who protected his plants by means of empty 

 tin cans with both ends removed and placed over the plants. 



We found that a barrier made of boards could be used successfully 

 for the protection of small patches of vegetables. Any kind of boards 

 may be used but if narrow they should have one side smooth. The 

 boards should be placed tightly on one edge on the ground with the 

 ends fitting tightly. Vessels are buried with the tops level with the 

 surface of the ground at intervals against the boards, both inside and 

 outside. As the beetles wander about they come to the boards and 

 follow them till they fall into the vessels where they remain. On 

 account of their heavy, clumsy bodies they are able to climb even a 

 rough perpendicular surface only a few inches. They have been 

 observed many times trying to climb a board but nearly always falling 

 back. In a fewinstances they have been seen to cross a four-inch board. 

 It is impossible for them to escape from buried vessels which have 

 smooth inner surfaces. After a few nights nearly all the beetles were 

 caught from within the barrier but picking some by hand each night 

 would more speedily rid the part inside the barrier from the beetles. 



Barrier Experiments. — We constructed seven of these barriers 

 in all as described above. They were all located in the southern part 

 of the city near the laboratory where the beetles were not so numerous 

 as they were in the northern part. The beetles were removed from 



