14 MONTANA EXPERIMENT STATION BULLETIN 474 



OTHER IMPORTANT PESTS 



MORMON CRICKETS (Anahrus simplex) 



In general, Mormon crickets appeared to be building up in 1949. 

 This condition was more apparent in 1950. Although no crop dam- 

 age occurred either year, it was considered advisable to treat sev- 

 eral of these cricket build-up areas in an effort to head off out- 

 breaks that may occur from these areas in future years. The largest 

 area baited in the 1950 preventive program involved some fifteen 

 sections of land which were primarily range lands and were located 

 in Cascade County south of Ulm. This baiting was accomplished 

 with a DC-3 aircraft owned by the Federal Bureau of Entomology 

 and Plant Quarantine in a program sponsored jointly by the Fed- 

 eral Bureau of Entomology, Cascade County, aiid the Office of 

 the State Entomologist. In spite of considerable rain on the toxa- 

 phene dry bran bait, shortly after and for some period after appli- 

 cation, the results were excellent. 



In addition to the area baited in Cascade County, the Federal 

 Bureau of Entomology baited 1,600 acres of federal land southeast 

 of Hardin. This was accomplished with smaller aircraft owned 

 by the Bureau of Entomology. 



It is practically impossible to predict with any degree of ac- 

 curacy the probable Mormon cricket infestations in the next sev- 

 eral years. It is, however, clear that during the past several years 

 Mormon crickets have been building up in Montana. It is, there- 

 fore, reasonable to assume that one or more Mormon cricket out- 

 breaks can be expected in the state in the relatively near future. 

 Fortunately, we now have the insecticides and methods to success- 

 fully and economically fight Mormon crickets. It is hoped that 

 it will be possible to prevent outbreaks by the elimination of out- 

 break source areas as they become known. 



GARDEN SLUGS (Agriolimax sp.) 



Garden slugs have been an important pest to home gardens in 

 the western and south central parts of the state during the last 

 two years. In general, they appeared to be more numerous in 

 1949 than in 1950. Baits containing metaldehyde with sodium 

 fluosilicate or an arsenical as the toxicant have been effective. 



WHITE GRUBS (Phijllophaga spj 



The observation in the last biennial report, "It appears that 

 white grubs are becoming more common throughout the state", 

 apparently was correct. During the last two years white grubs 

 have been reported or found in nearly every county in the state. 

 Economic damage has occurred in some cereal crops, potato plant- 

 ings, and strawberry beds. In most cases, this damage occurred 

 where plantings were made on land that was previously in sod. 



