214 



THE MONTHLY BULLETIN. 



Fig. 41. — The pear or cherry 

 slug and its work upon the leaf 

 (After Ewing. ) 



The Cherry and Pear Slug. 



The pear and cherry are the principal hosts of this destructive pest. 



This, like many of our dreaded insects, is of European origin, and is 



generally distributed where the cherry and 

 pear are grown. The insect belongs to tlu^ 

 same order of insects as bees and wasps. 

 The larva is generally known as a slimy 

 greenish or brown, large headed worm, 

 which is found feeding in the summer ou 

 the green parts of the leaves, making them 

 appear gray and dead. The slugs may be 

 destroyed hy arsenical sprays, by "Black 

 Leaf 40," or by dusting the leaves on which 

 the slugs are feding with lime, or even road 

 dust. The last named irritates the slugs, 



which drop to the ground and soon die. The strength of the arsenate 



of lead spray is about 4 pounds to 100 gallons of water, and the "Black 



Leaf 40," 1 part to 1000 parts of water. 



The Peach Tree Borer. 



The principal friTit trees attacked by the larvae of the peach tree borer 

 are the peach, apricot, plum, prune and cherry. In this State the 

 distribution of this insect has been given as the Santa Clara Valley, 

 Alameda, San IMateo, Ventura and Riverside counties. The adult tree 

 borer is a clear winged moth, and emerges late in the spring from 

 the resting stage to la.y its eggs on the bark of the host plant, a few 

 inches above the surface of the soil. The newly emerged worms bore 

 through the bark and start new tunnels, in the sap wood. The indica- 

 tion of the presence of the borer is an exudation of gum by the host, 

 which is often mixed with sawdust and frass. The full grown larva is 

 about one inch in length, and yellowish or pinkish in color, with a 

 dark colored head. It remains in the burrows in the trunk of the 

 tree during the winter months, transforming to the pupa in the spring 

 months. 



Remedial measures consist in cutting out the larvffi from the burrows 

 with a sharp knife during the spring or fall, and applying hard asphal- 

 tum grades " C " and " D " to the tree trunks. This prevents the issuance 

 and entrance of a large number of these pests. The warm asphaltum 

 is placed from five to six inches below the surface of the soil with a 

 brush, two coatings being put on. 



The Flat Headed Apple Tree Borer, 



The larva of the flat headed apple tree ])orer is a yellowish legless 

 grub, having the anterior portion of the body enlarged and flattened. 

 Of tile fruit trees, the principal host is the apple. The borers work 

 principally in the sap wood, often boring in to the solid trunk, and 

 in the case of young trees, complete girdling may result from their 

 attack. Usually unhealthy trees or those that have been wounded 

 or sunburned are selected by the beetles, upon which to lay their eggs. 

 Discolored bark and the exudation of sap indicate the presence of the 

 grubs. 



