PLUM PESTS 



1699 



through the side of the fruit, making a 

 rather large, circular hole. This insect 

 is the plum gouger, Coccotorus prunicida. 

 It is slightly larger than the plum cur- 

 culio, lacks the warts or humps of the 

 latter on the wing covers, and has many- 

 short, whitish hairs which give it a prui- 

 nose or light-colored, dusty appearance. 

 Until it escapes from the fruit, there is 

 generally no indication of its presence, 

 except possibly a small scar from which 

 the gum exudes. Occasionally a mal- 

 formed fruit indicates its presence. The 

 pupal stage is passed in the pit and the 

 fruit seldom falls until the beetle is just 

 ready to escape. By far the most effect- 

 ive remedy is to pick and destroy the in- 

 fested fruit as fast as it falls, because 

 spring spraying is not very successful. 

 Hogs running in the plum orchard do the 

 work very well, but where these animals 

 are not available, or are objectionable, 

 pick up the fruit by hand and feed to 

 hogs, or burn or bury fully two feet deep. 

 The beetle hibernates over winter. This 

 insect is quite injurious in the states fur- 

 ther west, but so far as known, it causes 

 little or no damage in Ohio. 



H. O. GOSSARD, 

 Wooster, Ohio. 



Plum Web Worm 



Lyda ruflpes Marlatt 



The gregarious false-caterpillars of a 

 saw fly which web together the leaves of 

 small branches and strip them of all 

 green cellular portions in a very similar 

 manner to the larvae of the cherry-tree 

 tortrix. 



Seems to be distributed in Minnesota 

 and the Dakotas northward into Mani- 

 toba. Plum trees in Manitoba are report- 

 ed to have been defoliated one year by 

 them. 



The eggs are deposited in close masses 

 along the under side of the mid-rib of the 

 leaf, the long axis of the eggs lying par- 

 allel with the mid-rib. The younger 

 leaves are invariably selected, and the 

 eggs laid before the leaves are expanded. 

 Immediately on hatching, the young 

 larvae begin to spin a web and feed 

 through or crawl over to the upper sur- 

 face of the leaf. As they continue to 



grow, they travel to other leaves and 

 spread over the whole side of a tree be- 

 fore the insects have become full grown. 

 When ready to pupate the larvae go to 

 the ground and gradually envelop them- 

 selves in cocoons, turn to pupea and 

 emerge again the next year in the late 



San Jose Scale on Plum Twig:. 

 (Purdue Exp. Sta.) 



