16 MONTANA EXPERIMENT STATION BULLETIN 504 



SPIDER MITE (Order: Acarina) 



Many light to moderate infestations of spider mites occurred on rasp- 

 berries and coniferous trees ov'er most parts of the state during the biennium. 

 These infestations are always more severe during dry weather and especially 

 during the midsummer months. Malathion spra\s have been used in most 

 control programs with good results. 



COTTONY MAPLE SCALE (Pulvinaria vitis) 



Only one infestation of this pest was reported during the biennium. 

 This occurred on box elder in 1954 in Park County. 



OYSTERSHELL SCALE ( Lepidosaphes ulmi) 



Oystershell scale was present during the biennium ov^er wideh' scattered 

 parts of the state, especially in unattended orchards and on bacWard fruit 

 trees. ^^'here severe infestations developed, they were controlled very 

 readily with dormant sprays. 



VIRGINIA CREEPER LEAF HOPPER (Erythroneura ziczac) 



The \'irginia creeper leaf hopper has caused much damage throughout 

 the state during the last year. The central part of the state, Chouteau and 

 Cascade counties in particular, appeared to be the hardest hit. In some 

 areas Virginia creeper had to be pulled out. as it was damaged beyond a 

 point where it could be rejuvenated. This pest is successfully controlled 

 with DDT sprays and dust. 



ROSE CURCULIO (Rhyncbites bicolor) 



The rose curculio occurred in ecomonic numbers in Lake, Gallatin, 

 and Missoula counties during the biennium. Local and moderate damage 

 occurred throughout most of the state. Since this insect may live over and 

 reproduce on wild roses, there is little which can be done to eliminate it 

 from areas where these wild hosts exist. However, it may l>e prevented from 

 damaging garden roses by the use of a DDT spray. 



SPINY ROSE GALL (Diplolepis bicolor) 



One infestation of this insect was reported from Lake Count\' on roses 

 in 1954. This hymenopterous insect causes unsightly galls to form on the 

 main stem of rose bushes. 



POPLAR SAWFLY (Tnchiocampus viminalis) 

 One infestation of this pest was recorded in Libert\- Countv' in 1954. 



THE GRAPE LEAF HOPPER (Erythroneura comes) 

 In 1954 Beta grapes in Fort Benton were infested In tliis sucking insect. 



