24 MONTANA EXPERIMENT STATION BULLETIN 384 



Pale Western Cutworm. — The State has experienced several 

 years now with no outbreak of the pale western cutworm (Agrotis 

 orthogonia Morr.) . It was last important in the spring of 1937. 

 The abundance of this pest is dependent on the rainfall during 

 May, June, and July of the previous year, and it is possible to pre- 

 dict in advance the areas where injury may be expected. Weather 

 data for the spring of 1940 would indicate that it may be a minor 

 pest during 1941 in the Yellowstone Valley from Forsyth to Liv- 

 ingston, and in Golden Valley, Musselshell, central Liberty, south- 

 ern Lewis and Clark, and Beaverhead counties. Control measures 

 for this insect have been discussed recently 1 and will not be repeat- 

 ed here. 



Codling Moth. — In the apple districts of western Montana the 

 codling moth (Carpocapsa pomonella (L.) ) increased markedly in 

 1940 over any previous year. Average catches of moths in bait 

 traps went as high as 75.8 for a two-day period. For the first time 

 this pest became sufficiently abundant in the Bitter Root and parts 

 of the Flathead Valley to become one of the foremost problems of 

 the apple orchardist. Conditions during June, July, and August 

 were ideal, and even with good spraying programs the loss was 

 fairly high. However, property executed spraying programs very 

 decidedly paid for themselves even under conditions of a short crop. 

 The use of bait traps for the collection of adults as an indication 

 of the timing of the cover sprays is becoming more important, and 

 investigations into their use are being continued by Mr. Wm. R. 

 Forsyth, graduate assistant, who was stationed in the area in 1940. 



Termites. — Two species of termites have been found in Mon- 

 tana, the damp wood termite (Zootermposis nevadensis (Hagen) ) 

 which has been collected near Hamilton and doubtless has a wider 

 distribution west of the Divide, and the barren-land subterranean 

 termite (Reticulitermes tibialis (Banks)). This latter species (fig- 

 ure 7) is widespread in the State and occasionally damages build- 

 ings. It has been collected in or near the following cities in Montana: 

 Billings, Hardin, Havre, Helena, Jefferson Island, Kalispell, Miles 

 City, Powderville, Terry, and Whitehall. The workers, soldiers, 

 and wingless sexual forms are found in tunnels in wood which have 

 been excavated by the workers. This species is not a major pest 

 in the State, but occasionally it is extremely injurious in dwellings. 

 Its presence is usually first noticed because of a buckling or the ap- 

 pearance of holes in the floor, or the swarming of slate-colored 

 winged adults in the rooms. Houses as far north as Havre have 

 been attacked by this insect. Much has been published on the con- 

 trol of the termite and on the prevention of its entrance into houses. 

 Information can be obtained by writing to the Montana Agricul- 



: Mont. Agr. Exp. Sta. Bui. 366, p. 22, 1939; Mont. Ext. Ser. Bui. 176, p. 

 $6, 1939. 



