SEVENTEENTH ANNUAL REPORT OF STATE ENTOMOLOGIST 13 



second brood of the moth to develop. I do not expect that in 

 other years the codling moth will be as serious in Montana as in 

 some other states because of the natural limitations placed upon 

 a second brood. It will, however, be sufficiently abundant to cause 

 loss to fruit growers and energetic measures should be adopted to 

 hold it in control. Fruit growers who have codling moth should 

 spray for it. Most fruit growers have more than one insect pest 

 or fungous disease and all should adopt a spraying program which 

 should be consistently carried out year after year. 



LEAF-ROLLER OF THE APPLE 

 Our attention has been called to the leaf-roller which appeared 

 in injurious numbers on apple trees in the Bitter Root Valley in 

 3919. In some instances large numbers of trees were more or less 

 completely denuded. It is impossible for us to say at the present 

 time which one of two species is the cause of the trouble. The 

 fruit-tree leaf-roller {Archips cn'oyrospila ^^^alker) is sometimes 

 spoken of as the Colorado leaf-roller and growers locally have spoken 

 of this as being that insect. However, in past years we have in a 

 number of instances reared the oblique-banded leaf-roller {Arcliips 

 Tosaceana Harris) from the Bitter Root Valley. In some instances 

 this latter insect has done rather serious damage to a limited number 

 of trees. We shall have to wait for further developments of next 

 season before we can determine which of these species is present. 

 Satisfactory results in control can be secured by the use of miscible 

 oils applied as a spray in the spring as soon as the weather warms 

 up sufficiently to make spraying operations possible. It is not 

 believed that this will be a pest which will continue year after year. 

 Its history has been that it has occurred intermittently. 



FLEA BEETLES 

 The season of 1919 was notable for the number of flea beetles 

 which occurred. These minute beetles, with swollen hind legs 

 enabling them to jump away when disturbed, are present more or 

 less generally in small numbers each year but in the past season 

 they occurred in such numbers as to cause rather extensive damage 

 in gardens, on tomato and potato plants, and in sugar-beets. These 

 insects work early in the season, destroying young plants soon after 

 they come out of the soil. The stand in sugar-beet fields is some- 

 times seriously reduced by great numbers of flea beetles completely 



