348 The Principles of Fruit-growing 



GYPSY-MOTH (Porthetria dispar). The full-grown caterpillar is 

 about 2 inches long, dark gray in ground-color, with eleven pairs 

 of prominent tubercles on the back, the first five pairs blue, the 

 last six dark red. They become full grown about the first of 

 July. They pupate in slight cocoons. The moths emerge in 

 seven to seventeen days. The male has a light brown body, 

 wings yellowish brown, and each front wing is crossed by four 

 wavy, dark brown lines. In the female the body is light buff and 

 the wings grayish white. The dark markings on the front wings 

 are similar to those of the male. The females do not fly, but each 

 lays its eggs in a mass about an inch in length covered with hairs 

 from its body. Hibernation takes place in the egg-stage. The 

 eggs hatch just as the buds are bursting. 



Kill the eggs by saturating the masses with crude coal-tar 

 creosote, to which a little lamp-black has been aded as a marker. 

 When the young caterpillars hatch, spray the trees with arsenate 

 of lead, ten pounds in one hundred gallons of water. When the 

 caterpillars are half grown, use thirteen to fifteen pounds of lead 

 arsenate. Full-grown caterpillars are very resistant to poisons. 

 Band the tree trunks with tanglefoot to prevent the ascent of 

 wandering caterpillars. 



OYSTER-SHELL SCALE (Lepidosaphes ulmi). This is an elongate 

 scale (sometimes called bark-louse), % inch in length, resem- 

 bling an oyster-shell in shape, and often incrusting the bark. 

 It hibernates as minute white eggs under the old scales. The 

 eggs hatch during the latter part of May or in June, the date 

 depending on the season. After they hatch, the young may be 

 seen as tiny whitish lice crawling about on the bark. When 

 these young appear, spray with kerosene emulsion, diluted with 

 six parts of water, or whale-oil or any good soap, one pound 

 in four or five gallons of water. When trees are regularly sprayed 

 with lime-sulfur, as for the San Jose scale or blister-mite, the 

 oyster-shell scale is usually controlled. This is a very prevalent 

 pest, and should be kept under complete control. 



PALMER WORM (Ypsolophus pometellus). The brownish green, 

 white-striped caterpillars, % inch in length when mature, 

 skeletonize the tender foliage in June and eat holes in the young 

 apples. There is only one brood a year. 



Spray with arsenate of lead, four pounds in one hundred gal- 

 lons of water, when the caterpillars first appear. 



