MONTANA EXPERIMENT STATION. 



153 



or another locality while those that' are already widely distributed 

 and well known, such as the apple leaf-aphis, have been excluded. 



Not all of the species in the list can be considered to be pests of 

 first class importance in our climate but they are all species that for 

 one reason or another, usually because they feed in the fruits that 

 are liable to be shipped into the state or because they hibernate in 

 or on some part of the trees that are shipped in as nursery stock, 

 are liable to come across our borders incidentally in commercial 

 practices. 



THE PEACH-TREE BORER. 



Though the peach-tree borer shows a decided preference for peach 

 trees it is also a pest of cherry, plum, nectarines and apricots. The 

 insect is tiierefore of interest to the fruit-growers of Montana, 

 though few peaches are grown. It is not probable that it will be- 

 come a very serious enemy of cherries and plums, but it is thought 

 best to include it in the list here treated. 



The young larva burrows beneath the bark and sap wood during- 

 the first year of its life and passes the winter in this burrow. In 

 the spring it resumes feeding, reaching full growth in May or June. 

 In its hibernating condition it is liable to be transferred on nursery 

 stock 



It s a difficult pest to control and one that should be vigorously 

 dealt with if it is found in Montana. Its presence on growing trees 

 is indicated by gummy extraction from the, bark at the points where 

 its burrows touch the exterior. 



Fig. 2. The Peach-tree Borer: a, female; b, male; c, larva; d, e, female 

 and male pupae; f, cocoon. (Marlatt, Circular 17, New Series, Div. of En- 

 tomology, U. S. Dept. of Agr.) 



