CHAPTEE XIV. 



INSECTS INJURIOUS TO THE HOP-PLANT. 



INJURING THE STALK. 



The Hop-plant Borer {Hydrcecia immanis Grt.). 



The Hop-plant Borer is sometimes the occasion of a 

 considerable loss to the hop industry, Mr. Chas. R. Dodge 

 having estimated upon the basis of the census of 1879 that 

 it annually amounts to $600,000 in New York State alone. 

 The moths have been taken from Ontario and New Eng- 

 land south to the District of Columbia, and west to 

 Wisconsin, and also from Colorado and Washington, but 

 the larvffi have never become injurious in the hop-fields of 

 the Pacific Coast. *^It is probable that it is a northern 

 form, and confined, as it seems to be, to a single food- 

 plant, it will be found only where this plant is known to 

 grow. " * 



Life-liistory . — Many of the moths emerge from the 

 pup^e in the fall and hibernate over winter, while others 

 do not transform till spring, passing the winter in the 

 pupal stage, in a small cell in the ground near the roots 

 of the i^lant which the larv^ have infested. The moths 

 appear during May, and the females deposit their globular, 



* "Some Insects Affecting the Hop-plant," L. O, Howard, Bull. 

 No. 7, n. s., Div. Ent., U. S. Dept. Agr., p. 41. 



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