NURSERY AND ORCHARD INSECT PESTS 



23 



The adult is about the size of a garden pea and is blotched with brown, 

 gray and black. It has a short, stout snout and rather distinct humps or bumps 

 on the back. It passes the winter in the adult stage in rubbish and other pro- 

 tection. In the spring about two weeks after apple blossoms fall or when wild- 

 goose plums are the size of the tip of ones small finger, the adult appears on the 

 fruit, cutting crescent gashes for egg laying or circular pits for feeding. When 



these eggs hatch especially in stone fruits 

 the yellowish white footless grub bores 

 down into the fruit to feed. It is the typi- 



^^^Brfjjj^jj^^ cal slightly curved worm found in plums 



i<^ which ripen prematurely and in wormy 



peaches. The fullfed worms in central 

 Missouri leave the fruit in about three 



*^ & ^ weeks after the eggs are laid. These en- 



ter the soil to pupate, and around the mid- 

 dle to the last of July they again emerge 

 as the adults. These may feed on fruit un- 

 til Fall and are usually responsible for 

 most of the plum cruculio injury to apples. 

 There is normally one brood a year, tho 

 often in unusual years as in 1920 larvae may be found feeding in peaches 

 as late as September. 



CONTROL. This pest can be controlled in part by poison sprays, and the 

 spray applied one week after the calyx spray is so timed as to reach the adults 

 while making the egg and feeding punctures soon after the fruit sets. It 

 should be remembered, however, that sprays are less effective for this pest than 



FIG. 26. Plum Curculio; adult 

 curculio, much , enlarged. (After 

 Stedman) 



I 



FIG. 27. Plum Curculio; apple showing typical crescent gashes made by plum curculio for 

 placing eggs. (After Talbert) 



for the apple worm. For this reason the sprays should be supplemented by the 

 practice of clean culture to destroy the overwintering adults, the prompt dis- 

 posal of wind-fall fruit with the enclosed worms and, where practical, shallow 

 cultivation under stone fruit trees during July to destroy the soft, helpless rest- 

 ing stage of the pest. On small trees it is possible to jar the adults onto sheets, 

 when they begin to attack the fruit, and thereby destroy them. Since this spe- 



