34 MASS. EXPERIMENT STATION BULLETIN 353 



Control. Raking and burning the leaf litter in the autumn after all the leaves 

 have fallen should kill many of the hibernating pupae. 



Spraying the foliage with 4 pounds of lead arsenate to 100 gallons of water is 

 recommended when serious defoliation is threatened. 



Bailey, H. L. Vt. Dept. Agr. Bui. 35:34-35. No date. 



Felt, E. P. N. Y. State Mus. Mem. 8(2) :540. 1906. 



Herrick, G. W. Cornell Ext. Bui. 417. 1923. 



Packard, X. S. Fifth Rpt. U. S. Ent. Comm. pp. 408-409. 1890. 



Swaine, J. M., and Hutchings, C. B. Can. Dept. .A.gr. Bui. 63, N. S.:ll-12. 1926. 



Norway Maple Ncpticula 



Nepticida sericopeza Zeller. 



This European moth, now known to be present in parts of northeastern LInited 

 States, was first found here in 1928. The larvae occasionally tunnel in the petioles, 

 or leaf stems, of the Norwaj' maple, causing the affected leaves to drop about 

 June. This injury, however, is limited to trees which are not producing seed at 

 the time, because the normal habit of the insect is to attack the keys, or winged 

 maple seeds. 



There is little about the fallen leaf to suggest the cause of its dropping, but the 

 lower part of an affected leaf stem next to the twig is slightly enlarged and shows 

 a somewhat characteristic, variable, sooty black discoloration for a distance of 

 about 3^ inch. At a point almost exactly 3^ inch from the base of the leaf stem 

 there is a white, elevated, oval speck. 



The seeds, however, are usually preferred. There is a sooty discoloration 

 along the suture between the two seeds. A white spot is also present. Burrows 

 present in the thickened parts of the seeds are partly filled with somewhat charac- 

 teristic rust-red borings, or castings. Although this insect is not considered 

 destructive, yet it may cause a heavy leaf fall on trees failing to produce seeds. 



Life History. The insect hibernates in a flattened, oval, pale orange-yellow 

 cocoon about 3/16 inch long, usually on the bark but occasionally on the fallen 

 keys. Toward the latter part of May or early June the moths emerge and lay 

 their eggs on the developing seeds. The somewhat pale yellowish-green larvae 

 mine in them. Cocoons of the next generation are commonly found in early July 

 on the seeds and leaves. The moths emerge within a week. There are two, and 

 perhaps three, generations a year. 



Control. A sticky spray composed of J^ pint of 40 percent nicotine sulfate, 

 3 pounds of soap, and 2 quarts of molasses to 40 gallons of water is recommended, 

 and should be applied toward the latter part of May, to kill the moths which have 

 emerged and prevent others from emerging from the cocoons. 



Felt and Bromley have recommended a dormant application of a miscible oil 

 to destroy the cocoons. i Oil sprays should not be applied during freezing weather 

 or when freezing temperatures are apt to occur soon after the application. The 

 spray should be mixed according to the manufacturer's directions. 



Felt, E. P., and Bromley, S. W. Jour. Econ. Ent. 23(1) :137-142. 1930. 

 Felt, E. P., and Bromley, S. W. Proc. Ent. Soc. Wash. 32:146-149. 1930. 

 Felt, E. P., and Bromley, S. W. Jour. Econ. Ent. 24(1):157-159. 1931. 

 Felt, E. P. Proc. Eighth Nat. Shade Tree Conference, p. 80. 1932. 

 Felt, E. P., and Bromley, S. W. Bartlett Tree Res. Bui. 2:14-15. 1937. 



Ipelt and Bromley report that this treatment is safe on Norway maple. It is not safe on other 

 species of maple. 



