36 MONTANA EXPERIMENT STATION BULLETIN 294 



Th(> (Miorry Fruit-Fly {Rhiujoletis fausfa (). S.) 



This insect, which has occurred in relatively small numbers on 

 the east side of the Flathead Lake for several seasons, was more of a 

 scare than a problem in 1934. It prefers to oviposit in sour cherries 

 and most of the orchards of the locality consist of sweet varieties. The 

 population of flies was so small the past season that efforts at control 

 seemed wasted. However, in 1933, tbey were more numerous and 

 judging from the large number found in wild pin cherries, this in- 

 sect is at least an important potential pest. Next season may throAv 

 new light on the situation. 



Yellow Jackets {Vespidae) 



This insect appeared this year after most of the Flathead cherry 

 crop was harvested. A few attempts at control gave very poor re- 

 sults. These pests become very serious in some seasons and no satis- 

 factory control method is known. Luckily there is some natural force 

 which reduces the wasps to a minimum following a season of great 

 abundance. 

 Miscellaneous Cherry Insects of Flathead Orchards 



In orchards on recently cleared land various insect defoliators 

 noticeably affect the young trees for the first two years. Several 

 species of beetles and caterpillars were responsible. Hand-picking 

 methods usually suffice in controlling them. Tent caterpillars, fall 

 M'Cbworms, red-humped caterpillars, yellow-necked caterpillars, and 

 several solitary species were found feeding on the foliage of the 

 larger trees. 

 The Oystershell Scale {Lepidosaphes idmi L.) 



This is the predominant insect pest of apples in the Flathead 

 region. Trees have been and are being killed or made worthless by 

 the heavy incrustations of scale. Lime sulphur does not seem to be 

 as effective as in the Bitter Root Valley. Many orchardists have been 

 attempting to use lye as a dormant spray but it kills only a small 

 percentage of the eggs. The use of dormant oils has been prejudiced 

 by i>oor results obtained in the fcAv cases where they were poorly 

 applied. 

 The Codling Moth {Carpocapsa pamonella L.) 



In warm seasons the codling moth causes heavy loss of apples 

 in the Missoula and Kalispell districts. It does not occur in the 

 orchards on the east side of Flathead Lake although it has no doubt 

 been carried into that section dozens of times on apple boxes, etc. 



