170 MONTANA EXPERIMENT STATION. 



OTHER SCALE INSECTS. 



There are a few other scale insects that might be discussed in 

 this paper but which are not liable to often appear on nursery 

 stock arriving- in Montana. 



Scale insects are not easily identified except by the expert, and 

 much may depend on the identity of a scale that is found in an or- 

 chard or nursery. The Experiment Station will gladly make de- 

 terminations of scale insects or any others that are sent in. 



THE CODLING MOTH OR APPLE WORM. 



The well known apple worm is enormously destructive to apples 

 and pears in the United States. It is said to destroy, on an average, 

 about one half of the apple crop of the United States annually. Its 

 injuriousness is much less in Montana than in some other states 

 where the climatic conditions are more favorable to it but we believe 

 that the percentage of damage tmder ordinary conditions will vary 

 from about 15 to about 55 when nothing is done to hold it in check. 

 The apple is Montana's most successful fruit and the codling moth 

 its worst insect enemy. 



The codling moth is two-brooded in Montana. The first eggs 

 of the season are laid about the middle of June. By the latter part 

 of July wormy apples become noticeable. The second brood be- 

 gins its operations about the loth to the 15th of August and is prin- 

 cipally injurious to fall and winter varieties. 



It occurs in a few isolated localities in the following counties: 

 Flathead, Sanders, Missoula, Ravalli, Broadwater, Yellowstone, and 

 Custer. 



For means of wide distribution the codling moth is mainly depen- 

 dent on traffic in fruits. It has extended itself throughout prac- 

 tically the whole world and is believed to have done so almost en- 

 tirely through the medium of fruit packages. It is a particularly 

 dangerous practice to carry second hand fruit boxes into the orchard 

 to be filled again. This practice is now prohibited by law. 



Fruit growers should heartily co-operate with the state authorities 

 in the campaign against this pernicious insect. 



