6 MONTANA BULLETIN 200 



that the excessive abundance of mosquitoes is due primarily 

 to conditions growing out of the practice of irrigating blue- 

 joint grass, alfalfa, and other crops. The soil is heavy and the 

 water is slow to seep away so that, following irrigation, pools 

 are left which create ideal breeding places. In irrigating blue- 

 joint grass it is a common practice to allow the water to flood 

 the fields for long periods, resulting in the breeding of mos- 

 quitoes on a gigantic scale. 



So abundant have the mosquitoes become in that district 

 that they now amount to a very serious problem for the resi- 

 dents of town and country alike. Clouds of them follow the 

 stock, dairy production is practically impossible, all stock rais- 

 ing is interfered with, labor both by horse and man alike is 

 made very difficult, and normal property values are interfered 

 with to the amount of millions of dollars. Residents have told 

 us that at times it is impossible to breathe because the insects 

 hover around the face in tremendous numbers and are drawn 

 in with the breath. Veils are often worn when it is necessary 

 to be out of doors and at times there is such a cloud of mos- 

 quitoes about the head that it is impossible to see clearly 

 through the veils. 



A number of other localities in the State are similarly af- 

 flicted with mosquitoes. 



It is highly desirable that steps be taken to relieve the situ- 

 ation as far as possible. In this connection the services of both 

 the Experiment Station and the Extension Entomologist are 

 required. It is the function of the former to conduct studies 

 and find remedies and of the latter to conduct surveys of ex- 

 isting conditions and to cooperate with the residents in putting 

 remedies into effect. 



In the case of mosquitoes, methods of control that apply 

 under many kinds of conditions have been worked out. Before 

 a thoroughly effective plan of control can be put into effect 

 under conditions such as those found in the Milk River Valley, 

 some further work by the Experiment Station is necessary. 

 There is much that may be done now by the Extension En- 

 tomologist, however, with the knowledge that we have. 



The general remedies that are used in the control of 

 mosquitoes are oiling of pools and removal of standing water 



