INJURIOUS INSECTS. 37 



Root-Galls. — See Root-Galls, under R. 



Root-Knot. — See Root-Knot, under R. 



Rose-Beetle. — See under Rose and Apple. 

 Pear. Apple-Tree Borer. — See under Apple. 



Bud-Moth. — See under Apple. 



CoDLiN-MoTH. — See under Apple. 



Flat-headed Borer. — See under Apple. 



Midge {Diplosis injrivora, Riley). — A minute mosquito-like 

 fly ; lays eggs in flower-buds when they begin to show white. 

 These hatch into minute grubs which distort and discolor 

 the fruit. New York and eastward. Prefers the Lawrence. 

 Introduced about twelve years ago from France. 



BemecUes. — Destroy the infested pears. Cultivate and 

 plough in late summer and fall to destroy the pupse, then in 

 the ground. 



Pear-Leaf Blister {Phytoptus Pyri, Scheuten). — A minute 

 mite which causes black blisters to appear upon the 

 leaves. The mites collect under the bud-scales in winter. 



Remedy. — Burn the twigs in winter or spray with kero- 

 sene emulsion. 



Pear-Tree Borer (Sesia Pyri, Harris). — A small whitish 

 larva, feeding under the bark of the pear tree. 



Remedy. — Same as for round-headed apple-tree borer. 



Pear-Twig Beetle {Xylehorus Pyri, Peck). — Brownish or 

 black beetle, one-tenth inch long, boring in twigs, produc- 

 ing effect much like pear-blight, and hence often known as 

 "pear-blight beetle." It escapes from a minute perfor- 

 ation at base of bud ; probably two broods. 



Remedy. — Burn twigs before the beetle escapes. 



PsTLLA (Psylla pyricola, Forst.). — A curious aphis-like in- 

 sect infesting the twigs of pear trees when the fruit is 

 setting. They are covered with a sticky material, and in 

 the honey-dew a fungus often develops, giving the twigs a 

 sooty appearance. Often does great damage. 



Remedies. — DifScult to combat. Spray with kerosene 

 emulsion just after the leaves have expanded, whilst the 

 nymphs ai-e young. Repeat, if necessary, within a period 



