Seventeenth Annual Report of the State 

 Entomologist of Montana 



INSECT PESTS OF 1919. 



THE MITES AND TICKS (ACARINA). 



Red Spider {Tetranychus bimaculatus Harvey). There was 



the usual number of reports of injury from this pest to raspberry 



and currant bushes. Beans in eastern Montana suffered somewhat 



from red spider attack. 



Pear-Leaf Blister Mite {Ei-iophyes pyj'i Pagnat). In general 

 the fruit crop of the Bitter Root Valley suffered less injury from 

 this pest during the past year than for several years previously. 



GEICKETS AND GEASSHOPPERS (ORTHOPTERA). 



Black Cricket (Gryllus assimilis Stew.). This common black 

 cricket was again present in Big Horn county. It was also reported 

 injurious in Rosebud and Yellowstone counties where it was com- 

 bated with poisoned bran mash the same as used for grasshoppers. 

 The best results were obtained when the arsenical content was 

 increased somewhat over the standard amount. 



Warrior or Yellow- Winged Grasshopper (Camnula pellucida 

 Scudd.). In ten counties of the state this grasshopper occurred in 

 enormous numbers and during the latter part of the summer the 

 State Entomologist's forces gave their entire time to aiding farmers 

 to save their grain fields from this insect. Lack of sufficient money 

 for traveling prevented a greater service to the state. 



Big-Headed Grasshopper {Aulocaya elliotti Thom.). In recent 

 years the big-headed grasshopper has not caused much difficulty, 

 but during 1919 it was encountered in great numbers in Gallatin, 

 Beaverhead, and Madison counties, where it was doing damage to 

 grasses. 



