THE OPvIENTAL MOTH AND ITS CONTROL / 



spraying with lead arsenate, 3 pounds to 100 gallons of water, with 

 the addition of fish oil or linseed oil, as an adhesive, in the propor- 

 tion of 4 ounces, or one fourth pint, to each pound of lead arsenate 

 used. This strength of the poison is sufficient to kill the larvae in 

 the early instars which occur about August 1 to 15 at Boston, Mass., 

 and vicinity. After the first of the larvae become half grown (about 

 August 15, or later) the concentration should be increased to 4 pounds 

 to 100 gallons of water, with the addition of fish oil or linseed oil 

 in the proportion stated above. 



If the spraying is to be done on trees very close to houses or 

 fences, where it is impracticable to use fish oil or linseed oil as an 



uue 6. — Norway maple defoliated by the oriental moth. The silver, or cut-leafed, 

 maple nearby does not show injury. 



adhesive, 1 pound more of lead arsenate should be used in each 

 of the above sprays. For best results spraying should not be delayed 

 later than 2 weeks before the first larvae will become fully grown 

 and begin spinning their cocoons. 



If the cocoons appear in small numbers and in low growth, they 

 can be crushed or hand picked and destroyed. 



SUMMARY 



The oriental moth was first found in the vicinity of Boston, Mass., 

 in 1906, the result of an unwelcome introduction with plants im- 

 ported from the Orient. It has spread slowly from the original 

 point, advancing only 14 miles — the greatest known distance, to the 

 northeast — in 26 years. It has only one generation annually in this 

 country. The adults measure l 1 /^ to iy 2 inches from tip to tip of 

 expanded wings. They are light yellow on the thorax and inner 

 portion of the wings, while other portions of the body and wings 



