APPLE INSECTS — BORERS AND MISCELLANEOUS 199 



washes recommended for the larger apple-borers will doubtless 

 prove effective should the insect again appear in injurious num- 

 bers in orchards. 



The Bronze Apple-tree Weevil 

 Magdalis cenescens Leconte 



In Oregon, Washington, Montana and British Columbia apple 

 trees, particularly young trees, are sometimes attacked and killed 

 by this small snout-beetle or 

 weevil (Fig. 190). Weak or 

 sickly trees are more hable to 

 attack . The insect may work 

 on the trunk, but more often 

 makes its tunnels under the 

 bark of the branches and may 

 continue its work after the 



trees are dead. The little. Fig. 190. — The bronze apple-tree 



plump, legless, white grubs weevil (x lO). 



about I of an inch in length may extend their narrow burrows 

 for an inch or two in various directions under the bark. Each 

 burrow ends in a little cell where the grub transforms, probably 

 in the spring, through the pupal stage to the adult or weevil. 

 There is apparently but one generation of the insect in a year, 

 the weevils emerging through small, round holes in the bark 

 from early April until August, and laying their smooth, shining, 

 yellowish-white eggs in little horizontal holes dug in the bark. 

 The slender, blackish-bronze colored weevils, measuring about 

 i of an inch in length, often feed upon the leaves of 

 apple and cherry, sometimes nearly defoliating small trees. 

 The wild food-plant of the insect seems to be a species of thorn. 



Two Chalcid parasites destroy large numbers of the grubs. 



The repellent soap and lye washes or the kerosene emulsion 

 recommended for the round-headed apple-tree borer have been 



