Orchard insects of the pacific northwest 



29 



larger size and conspicuous coloring. The adults hibernate in swarms 

 in crevices about trees and buildings, and the young, which hatch 

 from eggs laid in the spring, feed on the boxelder trees. 



Control consists mainly in prevention. Boxelder trees should not 

 be grown for shade in the vicinity of orchards, and those already 

 there should be replaced with other kinds of shade trees if possible. 

 The hibernating adults may be destroyed with a spray of kerosene or 

 strong oil emulsion. 



CLIMBING CUTWORMS 



In the spring, orchardists sometimes find that the opening buds on 

 their trees are being eaten into and often entirely devoured, although 

 no insects capable of causing the injury are 

 visible. A careful search among the leaves 

 or trash at the base of the tree will prob- 

 ably disclose the culprits. They are climb- 

 ing cutworms, smooth, grayish-brown or 

 blackish, greasy looking worms, usually 

 curled up but ranging in length from }{ inch 

 to IK inches when stretched out. They lie 

 quietly just beneath the soil, under a leaf, 

 or in a bunch of grass or alfalfa during the 

 day, and climb into the trees at night to 

 feed on the tender leaves and flower parts 

 of the expanding buds. Frequently their 

 presence is made known by many buds and 

 portions of buds on the ground under the 

 trees, dropped there by the worms as they 

 feed. At times dozens and even hundreds 

 of these worms may be found in the day- 

 time under each tree, and such numbers 

 cause severe damage. 



In the Pacific Northwest several spe- 

 cies of cutworms (Agrotis c-nigrum L. 

 (fig. 36), Abagrotis barnesii Benj., and 

 Euxoa spp.) are responsible for most of 

 the damage of this type done to fruit 

 trees. Their habits are similar. Most of 

 them spend the winter as small, partly 

 grown worms, coming out of hibernation 

 in the spring voraciously hungry. For a 

 time the tender buds of fruit trees offer 

 a very attractive food supply, and most of 

 the damage is caused over a relatively 

 short period. Later the worms feed on 

 alfalfa and other ground plants. When 

 full grown they construct cells in the soil, where they pupate, and 

 the orange-brown pupae are often turned up when the soil is plowed 

 or spaded. The moths emerge at various times during the summer 

 and are among the fairly large, dull grayish or brownish moths seen 

 flying about lights at night. There may be one or more generations, 

 but later generations are of little consequence, as vegetation is plen- 

 tiful by the time they appear. Eggs are deposited in the fall on the 

 trees or cover crops in patches of a hundred or more. After hatching, 

 the small worms feed for a time before goine; into hibernation. 



Figure 32.— Tarnished plant bug feed- 

 ing on peach bud. Twice natural 

 size. 



