56 OHIO EXPERIMENT STATION: BULLETIN 198 



destroyed by spraying thoroughly with kerosene emulsion, one part 

 of emulsion in twenty-five parts of water. Winter treatment is the 

 more satisfactory method, and the grower should endeavor to avoid 

 the necessity of treatment at other times. See Winter Manual. 



The Pear L/Eaf Blister Mite, Eriofhyes -pyri, gives evidence 

 of its presence about the time the young leaves become full grown. 

 Pinkish-thickish patches appear, sometimes extending over the 

 entire leaf. Later in the season these patches become corky and of 

 a dark or black color. Within these corky galls, myriads of micro- 

 scopic white mites can be found with a magnifying lens, these being 

 the. cause of the disfigurements observed. The young fruit, as well 

 as the leaf, is sometimes thus disfigured. The foliage often falls 

 and the fruit crop is sometimes lost. The only season when treat- 

 ment can be effectually applied is in the winter, but the symptoms 

 of the disease are here recorded in order that the insect's presence 

 may be recognized and, where present, a campaign for the following 

 winter prepared against it. 



The Pear Tree Blister Beetle, Pomphopaea aenea, greenish- 

 blue in color, inclining to a metallic luster and somewhat more than 

 half an inch long, attacks the blossoms of the pear, destroying first 

 the corolla and then the pistil and calyx. They will also eat portions 

 of the newly formed fruit. The remedy is to jar the trees in the early 

 morning. The beetles readily drop to sheets spread on the ground 

 for the purpose, and may be destroyed bybeing put into a pail of 

 water with a kerosene film over it. 



The Pear Slug, Eriocamf aides Itmacina,. is the larva of a small, 

 glossy black, four-winged insect about one-fifth of an inch long, that 

 appears on the wing in April and May. The eggs are laid beneath 

 the skin of the leaves of pear, cherry, quince and plum, hatching 

 about two weeks later. The young larvae, slimy snail-like creatures, 

 are not apt to attract attention until late May, at which time the 

 foliage attacked by them appears eaten or skeletonized on the upper 

 side, only the larger veins remaining undevoured. The grown slug 

 is about half an inch ^oHg, olive-brown or dirty green in color, having 

 the aiiterior segments of the body enlar jed and the posterior ones 

 tapering down to the tail, the whole body being somewhat shaped 

 into the form of a club. Dry-slaked lime freely dusted upon them 

 by hand, or vsdth a powder gun, will kill them. One part of hellebore, 

 mixed wich four parts of drj'-slaked lime, is still more effective. 

 Pyrethrum may be substituted for hellebore in the lime mixture, 

 and results will also be good. The arsenites are effective but cftre 

 should be used in applying them on fruits that are nearly matured 

 and quick in ripening, such as cherries. Even road dust will kiU. 

 the worms if it is thoroughly applied. 



