134 MONTANA EXPERIMENT STATION. 



weakened, because of the grubs at the root, and they harvested 

 very poor crops. The beetle has shown itself capable of wiping out 

 the strawberry industry in the territory in which it operates. Up 

 to this time we have been powerless to check its ravages. 



Fortunately it spreads very slowly or else is closely confined to 

 certain soil conditions. It has been a matter of much interest to us 

 that on the farm adjoining that of Mr. Williams, just across the road 

 and an irrigating ditch, strawberries ha^'e been grown very success- 

 fully. On one occasion I entered this field and found very luxurious 

 foliage and saw the pickers harvesting a full crop of berries, while 

 at the Williams place the crop was destroyed. After five years* 

 experience with the insect we feel warranted in saying that it is pro- 

 bable that it is quite definitely confined in restricted localities and 

 that excessive injury will result only when it is attempted to grow 

 strawberries in these localities. In dri-ving- up the Bitter Root valley 

 in the summer of 1902, I stopped b}' the road and collected insects. 

 It developed that I was in the midst of a colony of this beetle. 

 Masses of their dead bodies were to be found under pieces of bark 

 on the ground. So far as I was able to learn no one has ever 

 grown strawberries within several miles of this spot. The limits of 

 this colon V were not far off and bevond the limits no beetles were 

 found. The fact that the species is gregarious in habits may in part,, 

 but does not fully, explain this marked tendency to live in limited 

 areas. Fvirther, it may be said that the presence of the beetle in a 

 strawberry field in small numbers is not necessarily an indication tjiat 

 it will increase and become injurious. Though- we. have found the 

 beetle in garden patches of strawberries in the city of Missoula we 

 have never had a complaint from that city. 



It is not a usual practice to continue to grow strawberries on one 

 piece of ground year after year, and though a few specimens may 

 be brought into a bed it is not probable that they will multiply 

 with sufficient rapidity to become seriously injurious before the bed 

 is abandoned. We believe that serious injury wall be done only 

 where strawberry beds are planted on fields where the beetles are 

 already present in abundance. Literature shows no record of ex- 

 tensive injuries from this insect though its possibilites as a pest have 

 been mentioned. 



