528 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



dirty-gray color, irregularly shaped as shown in Fig. 456, c 

 The male scale is much smaller, elongate, snowy white, and with 

 three distinct ridges, Fig. 456, d. It is an American insect, 

 being common from Southern Canada to the Gulf States. The 

 life history, as far as known, is practically identical with that 

 of the last species. 



Control. As the last two species are practically identical in 

 habits, they may be controlled by the same methods. Where 

 the trees are sprayed with lime-sulfur wash for the San Jose scale, 

 there will be but little trouble with these scales, and where specific 

 treatment is required for them experiments indicate that a thor- 

 ough coating with the lime-sulfur wash while the trees are dor- 

 mant, preferably in the spring just before the buds open, is one 

 of the most effective remedies. The wash does not seem to kill 

 the eggs, but to kill the young soon after hatching, and has been 

 used successfully on both fruit and shade trees, but if there be 

 frequent rains in late spring, so that it is washed off, or if the 

 scales are very thick, it is not always entirely effective, but yearly 

 treatments will always prevent serious damage. 



Apple Plant-lice * 



Several species of aphids or plant-lice commonly infest the 

 foliage of the apple, and less commonly that of the pear, and 

 though they differ somewhat in appearance and habits they are 

 sufficiently alike to be discussed together, as the same methods 

 of control apply to all. 



The Apple-aphis f 



This is the common Apple-aphis of Europe, and was first 

 noticed in this country late in the last century, when it spread 

 to all parts of the country within a few years, probably being 



*See Sanderson, 13th Report, Del. Agr. Exp. Sta.; A. L. Quaintance, 

 Circular 81, Bureau of Entomology, U. S. Dept. Agr.; Gillette and Taylor, 

 Bulletin 133, Colo. Agr. Exp. Sta., Parrott, Hodgkiss and Lathrop, Bulletins 

 402, 415 and 431, N. Y. Agr. Expt. Station, Quaintance and Baker, Farmers' 

 Bulletin 804, U. S. Dept. Agr., and Robert Matheson, Memoir 24, Cornell 

 Agr. Expt. Station. 



t Aphis pomi DeG. Family Aphididce. See above references, and J. B. 

 Smith, Bulletin 143, N. J. Agr. Exp. Sta. ; C. P. Gillette, Journal of Economic 

 Entomology, Vol. I, p. 303, and H. E. Hodgkiss, Bulletin 461, N. Y. Agr. 

 Expt. Station. 



