APPLE PESTS 



503 



ing especially young apple trees, thus 

 dwarfing them. The work is particularly 

 on the leaves. Besides the apple it feeds 

 upon currant, gooseberry, blackberry, 

 pear, cherry, plum, thorn-apple, black 

 walnut, grapes, cottonwood, elm, birch, 

 maple, box-elder, hazel, choke-cherry, 

 sumach, oak. s.vringa. snowball, canaigre, 

 basswood, buckthorn, rose, buckeye, corn, 

 beans, potatoes, sugar beet, clover, 

 grasses, buckwheat, dahlia, rhubarb, 

 hemp, alfalfa, oats, celery and hollyhock. 

 Without doubt other plants are also at- 

 tacked. 



Control 

 The difficulty of control lies in the im- 

 possibility of killing the eggs without in- 

 juring the young trees. Successive spray- 

 ings with the oil emulsions, whale oil 

 soap solution of one pound to eight gal- 

 lons of water, or tobacco decoctions, as 

 often as the young become apparent, will 

 prevent serious attacks and hold the pest 

 in subjection. Affected nursery stock 

 should be thoroughly dipped in such 

 solutions before shipping. To prevent at- 

 tacks nurseries should not be located 

 near orchards or fields in which the 

 hopper breeds. All food plants should be 

 kept out of the nursery. Sticky shields 

 and hopperdozers may be used with good 

 effect. 



Natural Enemies 



The most effective natural enemy is the 

 small dark bug {Triphleps insidiosus 

 Say), which preys upon the nymphs by 

 puncturing their bodies and extracting 

 the contents. 



The larvae of the green lacewings also 

 prey upon the young hoppers. 



E. O. EssiG 



Apple Leaf Sewer 



Ancylis mibeculana 



The caterpillars of the apple leaf sewer 

 fold the edges of the leaves together, 

 commencing to feed inside the folded 

 leaf sometime in July and continuing 

 therein until the leaves fall in autumn. 

 The larvae is greenish-yellow, with a 

 yellow head and a horny plate of darker 

 color just back of the head. On each 

 side of the plate is a black dot. On each 



of the remaining segments are a number 

 of pale, shining, raised dots, from each 

 of which springs a single hair. When 

 full grown, the larvae line their nests 

 with silk and fall to the ground, remain- 

 ing in the caterpillar stage until next 

 spring. Sometimes the insect becomes 

 sufficiently numerous to cause serious 

 damage to the foliage. The summer 

 spraying with arsenicals for codling 

 worm doubtless kills many. Collecting 

 and burning the fallen leaves and other 

 rubbish is an excellent measure. 



Apple Leaf Skeletonizer 



Cana7-sia hammondi 



Nursery trees and sometimes young 

 trees recently transplanted from the 

 nursery are badly gnawed some seasons 

 by a brown larva, becoming finally about 

 one-half inch long, living, often a number 

 together, in the grooves above the mid- 

 ribs of the leaves under a light silken 

 web. Sometimes it draws several leaves 

 together and lives concealed among them. 

 This insect feeds upon green substance 

 of the leaves only, leaving finally only 

 the veins and veinlets, the foliage at a 

 distance then appearing as if scorched 

 by fire. Whole blocks of young trees in 

 the nursery may become thus Injured. 

 In the orchard it is less often seen, and 

 then appears most frequently on rather 

 young trees. 



This insect is well known in the upper 

 Mississippi valley from its injuries to 

 apple trees, but eastward appears to be 

 less well known. 



The larva reaches one-half inch in 

 length and may be recognized by four 

 round black dots back of the head. The 

 moth is slate gray, measuring about a 

 half inch from tip to tip. Paris green 

 or arsenate of lead in good season will 

 kill them. 



H. Garman 



Apple Maggot or "Railroad Worm" 



Rhagoletis (Tryeta) pomonella Walsh 

 The apple maggot, as the name implies, 

 is the larva of a fly or dipterous insect, 

 and belongs to the family Trypetidte, 

 which group contains numerous other 

 fruit-infesting maggots, some of them 



