596 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



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

 specific treatment is required for them experiments indicate 

 that a thorough coating with the lime-sulfur wash while the trees 

 are dormant, 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 



FIG. 449. The scurfy scale (Chionaspis furfura Fitch): a, c, females, 

 b, d, males a, b, natural size, c, d, enlarged. (After Howard, U. S. 

 Dept. Agr.) 



scales are very thick, it is not always entirely effective. In 

 England a 3 per cent caustic soda wash has proven very satisfactory 

 for killing the winter eggs. Recent experiments made by Professor 

 R. A. Cooley in Montana * show that emulsions of linseed or 

 cottonseed oils are very satisfactory when applied either in the 

 spring or as the eggs are hatching, and were more effective than 



* R. A. Cooley, Journal of Economic Entomology, 

 Webster, ibid. IV, p. 202. 



,^ p. 57; R. L. 



