18 MONTANA EXPERIMENT STATION BULLETIN 457 



fertility or other factors, some loss of canes has occurred in both 

 1947 and 1948. In 1948, the first adult activity was noted on 

 August 2nd. 



RASPBERRY FRUIT WORM {Byturus u7iicolor) 



This insect pest is found in varying numbers throughout the 

 state wherever respberries are grown. During the 1947 and 1948 

 seasons, damage by this insect was in general, slight. In the Bitter- 

 root sections, a spray application is frequently employed as a 

 precautionary measure. 



RASPBERRY SAWFLY (Blennocampa ruhi) 



The raspberry sawfly, although usually present where rasp- 

 berries are grown in the Bitterroot and Flathead valleys, is of 

 minor economic importance in these areas. In 1948, infestations 

 were more severe than in 1947. 



PRUNES AND PLUMS 



PLUM GOUGER (Anthonomus seiitellaris) 



The plum gouger M^as reported from the Billings area in 1948. 

 It has been recorded in past years, over most of the state where 

 plums are grown either as a commercial crop or for home use. In 

 general, it has been of little economic importance during the past 

 two years. 



PLUM APHIS (Aphididae) 



Damage from the plum aphis in sections of the Bitterroot was 

 more severe in 1948 than in previous years. Light to moderate 

 infestations occurred along the shores of Flathead Lake. Varietal 

 studies on plantings in the Bitterroot Valley indicate that some 

 varieties of plums, such as the Fiebing, are very susceptible to 

 plum aphis infestations, whereas Superior and other varieties are 

 moderately resistant. 



STRAWBERRIES 



STRAWBERRY CROWN MINER (Aristotelia fragariae) 



An infestation of this insect pest was recorded from the 

 Bitterroot Valley in 1948, where it was doing considerable damage 

 to plots of experimental strawberry varieties. Available informa- 

 tion indicates that this pest had been present for at least six years. 

 At this time nothing more is known about its distribution through- 

 out the state, except that it was reported from Lake County in 1944. 



