Montana State Library 



3 0864 1004 0571 4 



Fifteenth Annual Report of the State 

 Entomologist of Montana 



INSECT PESTS OF 1917 

 THE MITES AND TICKS (ACAKIXA) 



Red Spider [Tetranycluis hhnaciilafiis Har\ey). Red spiders 

 did considerable damage to raspberries in various parts of the State. 

 The older growth was most seriously damaged and in many cases 

 was completely killed. The new growth was severely injured later 

 m the season. Control experiments were carried out with various 

 insecticides with considerable success. 



Pear-Leaf Blister Mite (Kriophyes pyri Pagnat). Pear-leaf blis- 

 ter-mite was reported as being injurious to apples in the Bitter Root 

 \'allev and other localities in the western part of the State. Some 

 control experiments against this insect were carried on in conjunction 

 with the State Board of Horticulture. As had been previously dis- 

 covered, lime sulphur, sprayed when the buds were swelling, gave 

 satisfactory results.' 



COrKROACHES AXD GRASSHOPPERS (ORTHOPTERA) 



Cockroaches (Blatta germanica Linn.). As usual, there were 

 a few inquiries concerning the eradication of cockroaches in houses 

 and business establishments. 



Grasshoppers (Afclanoplus sp.). A grasshopper outbreak, cov- 

 ering the lower Bitter Root Valley, Missoula County, the Flathead 

 Indian Reservation, and Tobacco Plains was the most outstanding- 

 feature of the year. Smaller outbreaks occurred in the Missouri 

 \'alley between Three Forks and Townsend. Poisoned bran mash 

 was used earlier in the season, followed by grasshopper-catching 

 machines. The farmers caught many bushels of 'hoppers to use for 

 chicken feed. 



Shield-Backed Locust (Prrdiiabj-its scal)ricolli.<: Scud.). This 

 insect was found doing damage near Ronan. along with the .Melcnio- 

 plus spp. in the general outbreak. It did not take the poisoned bran 

 mash as readily as did the Alelanophis. 



THRIPS (THYSAXOPTERA) 



Grain Thrips (. / in(/)Ji(^fJirips sfriatiis Osb.). The sterility of 



