INSECT PESTS AND THEIR CONTROL 



999 



beneath the bark. The external indications of their presence are the mass 

 of sap which is commonly seen at the base of the tree and the frass or worm- 

 wood that has been worked out through holes in the bark. Preventive 

 means that have given some measure of success are various styles of pro- 

 tectors placed around the base of the trees, and coating washes applied to 

 the trunk. The latter are not satisfactory. 



Treatment. — Remove the ground from the crown of the tree in the 

 spring and fall and dig out the borers with a sharp knife. 

 Georgia Agri. Exp. Sta. Bull. 73; N. J. Agri. Exp. Sta. Bull. 235. 



Pear Leaf Blister Mite (Eriophyes pyri, Pagenstecher) . — This small 

 mite, only -j+s-inch in length, is the cause of the rough, blistered surface 

 of pear and apples leaves. When the attack is severe the trees become so 

 brown that they 

 have the appear- 

 ance at a dis- 

 tance of having 

 been swept by 

 fire. 



Treatment. 

 — Spray in the 

 spring or fall 

 with concen- 

 trated commer- 

 cial lime-sulphur 

 testing 33° 

 Baume, diluted 

 at the rate of 1- 

 10 or 11. 



Plant Lice 

 (Aphididce). — 



Many species of plant lice are found upon the various fruit trees grown 

 in this country. They feed by sucking the sap from the leaves and 

 stems and thus do considerable injury at times. Some species curl tin; 

 leaves about them so that they are very difficult to reach with a spray 

 unless the treatment is made before the attack becomes severe. The 

 treatment for all aerial forms is practically the same. 



Treatment. — Spray carefully with a 40 per cent nicotine sulphate solu- 

 tion diluted at the rate of 1 part to 800 parts of water, being sure to touch 

 all insects with the spray. A kerosene emulsion spray is also good if used 

 at the 8 or 10 per cent strength. 



Plum Curculio (Conotrachelus nenuphar, Hubst.). — On apples this 

 insect injures the fruit by deforming or scarring it by its feeding and egg- 

 laying punctures. 



Treatment. — Spray as for codling moth, except that one additional 



!Bur. Ent, Cir. 17. 



Peach Tree Borer 

 (Sanninoidea exitiosa). 1 



A — Adult female. B — Adult male. C — Full grown larva. 

 D — P^emale pupa. E — Male pupa. F — Pupa skin extruded 

 partially from cocoon. All natural size. 



