24 MONTANA EXPERIMENT STATION BULLETIN 484 



were found to be present, the water was treated with insecticides. 

 This control program was successful and Miles City enjoyed a near 

 mosquito-free summer. 



Many additional areas, principally towns and cities, are re- 

 questing mosquito control programs. In view of the successful 

 test at Miles City and with more fundamental information being 

 made available from the investigational work in Blaine County, 

 it appears that these requests are justifiable. The principal diffi- 

 culty now confronting such a program is enablement for locali- 

 ties including towns, cities, and counties to establish and carry out 

 mosquito control programs. 



CATTLE GRUBS (Hypoderma lineatum and Hypoderma bovis) 

 Since the last printing of this report, Montana State College 

 Agricultural Experiment Station bulletin 471 (technical) entitled 

 "Cattle Grubs — Their Biologies, Their Distribution, and Ex- 

 periments in Their Control" dated December 1950, has been 

 published. The data presented in this bulletin provide further 

 evidence that the present known methods of treatment fall far 

 short of the desired results in bringing about economic control 

 of cattle grubs. Cattle grubs continue to be an important economic 

 pest of cattle but treatment in many cases has been discontinued, 

 due to the practical experiences of many stockmen and the evi- 

 dence presented from the research mentioned above. 



CATTLE LICE (Anoplura and Mallophaga orders) 

 Cattle lice continued to be one of the more serious insect pests 

 of cattle during the reporting period. The two sucking species 

 Haematopinus eurysternus and Linognathus vituli and the one 

 biting species Bovicola bovis are the only species known to be 

 present in Montana. It appears that more cattlemen are recogniz- 

 ing the importance of cattle lice as insect pests to cattle and more 

 treatment programs are evident. Extensive efforts have been car- 

 ried out to direct these treatment programs along lines which 

 would bring about desirable results. These efforts include meet- 

 ings with stockmen using a silent motion picture film prepared 

 by the Assistant State Entomologist on the topic of proper spray- 

 ing for control of cattle lice and the circulation of publications, 

 newspaper stories, and radio talks. 



SHEEP TICKS (Melophagus ovinus) 

 The sheep tick, which is actually a parasitic fly and not a 

 tick, is common in all of the sheep-raising areas of the state. Fall 

 dipping with a rotenone suspension seems to be the most prac- 

 tical means of combating this problem. 



HORN FLIES (Siphona irritans) 

 A practical demonstration test of the South Dakota type of 



