44 



GRASSHOPPERS AND OTHER INJURIOUS INSECTS OF 1911 AND 1912. 



BLISTER BEETLES. 



One or more species of these soft-bodied Beetles, family Meloi- 

 dac, were extremely abundant and destructive in 1911. This was to 

 be expected on account of the great abundance of grasshoppers in 

 1909, 1910 and 1911, since the eggs of grasshoppers form the food 

 of one or more species of these insects 

 when in the larval stage. The relation 

 of these beetles to grasshoppers is dis- 

 cussed in this report in the article on 

 ''Grasshoppers." 



Unfortunately, the good done by 

 them in the larval or young stage 

 is more than offset by the injury 

 done to various crops in the mature 

 beetle stage. Specimens of these in- 

 sects sent to this office in 1911 and col- 

 lected in both 1911 and 1912 prove to be 

 the black and gray form of Macrohasis 

 unicolor. These beetles appeared in 

 enormous numbers in different parts of 

 the state almost simultaneously; i. e., 

 about June 1st, and after that date 

 letters of complaint gradually de- 

 creased until July 5th, or thereabout, 



after which there were, nevertheless, a few inquiries or 

 requests for assistance with this insect until nearly the last of 

 August. Alfalfa, clover, potatoes, various flowering plants, locust 

 trees, etc., were sought by these insects, and we found them very 

 difficult to poison in that they quickly left a crop so treated and 

 went to another before the poison had had an opportunity to make 

 any great impression on their numbers. We therefore advised 

 sweetening an arsenate of lead spray, (three pounds of arsenate of 

 lead in fifty gallons of water) where feasible to use spray. Where a 

 spray could not be applied and the plants affected not too numerous, 

 we suggested knocking them, off the plants in the cool of the morn- 

 ing into a pan containing a little kerosene. Immediate action must 

 be taken upon their very first appearance, otherwise they will 



Fig:. 30. 



A Blister Beetle. 



See also Fig. 22. 



