Montana State Library 



3 0864 1004 0545 8 



Eleventh Annual Report of the State 

 Entomologist of Montana 



INSECT PESTS OF 1913 



The season of 1913 was about normal in respect to the abund- 

 ance of insect pests. As usual some species appeared in more than 

 ordinary numbers and several new to Montana were discovered. A 

 brief record of the insects which were of particular economic impor- 

 tance in 1913 follows. For the sake of convenience they are classified 



by orders. 



ACARINA 



Leaf Blister Mite i^Eriophyses pjjri Pgst.). In neglected orchards 

 in the Bitter Root Valley this was the most injurious insect pest 

 of fruits. On both apple and pear it was worse than for several 

 years. Orchards which received the strong lime-sulphur spray just 

 before the buds opened were practically uninjured, which goes to 

 emphasize the importance of the dormant spray in the spraying 

 program of the successful orchardist. 



Plum Gall Mite (^Eriophyses padi Nal.). This close relative of 

 the leaf blister mite was very abundant in the eastern half of the 

 State. We have observed it for a number of years in the Yellowstone 

 Valley and this year it was sent in from Lewistown. It distorts 

 the leaves of both cultivated and wild plums, and in many instances 

 causes a loss of part of the fruit. 



The Bulb Mite {Rhizogyphus hyacinthi Boisduv.). This old- 

 world pest was found in a shipment of imported bulbs consigned 

 to a Montana florist. 



Clover Mite (Bryobia pratensis Garman). Some injury to sweet 

 peas and clover was caused by the clover mite during June and 

 July, but it was as a household pest that it attracted the most atten- 

 tion. In Missoula and in other towns it swarmed over the exterior 

 and into the interior of houses, causing much annoyance to the 



housewives. 



CORRODENTIA 



Book-louse {Tjvctes divinatoTia Fab.). A sample of wheat con- 

 tained in a glass exhibition jar was found to be alive with book- 



