SOME STONEFLIES INJURIOUS TO VEGETATION 



By E. J. Newcomer 



Scientific Assistant, Deciduous Fruit Insect Investigations, Bureau of Entomology, 

 United States Department of Agriculture 



INTRODUCTION 



Stoneflies (Plecoptera) are not ordinarily classed among the insects 

 injurious to plant life. Indeed, a study of the mouth parts of several 

 species has shown them to be more or less rudimentary/ so that, while 

 they are of the biting type, they are not capable of being used to inflict 

 injury upon plant growth. John B. Smith says^ that adult stoneflies 

 do no feeding upon living plants, so far as known. The writer has been 

 much interested, therefore, in studying the habits of several of the western 

 species of the genus Taeniopteryx (Taeniopteryx pacifica Banks, T. pallida 

 Banks, and T. nigripennis Banks), which are equipped with well-de- 

 veloped mouth parts, and which feed upon the buds and leaves of plants. 

 One species in particular, T. pacifica, has proved to be of considerable 

 economic importance in the Wenatchee Valley, in central Washington. 

 While it has not been possible to make detailed life-history studies, or to 

 work out satisfactory control methods, it has been thought advisable to 

 publish a short paper on the subject, owing to the unusual habits of these 

 species. 



OCCURRENCE 



When the writer arrived at Wenatchee, Wash., in May, 1914, he was 

 shown injuries to foliage and fruit which had been caused by an insect 

 known locally as the "salmon fly."' Unfortunately the insects had all 

 disappeared. However, the writer recalled an early experience in the 

 Yellowstone Park where insects known as "salmon flies" were plucked 

 from one's clothing or from the adjacent foliage and used as bait in 

 catching salmon trout from the Yellowstone River. These insects were 

 a species of stonefly, and the descriptions given the writer of the insect at 

 Wenatchee indicated that it was also a stonefly. During the following 

 two years (1915 and 1916) ample opportunity was afforded for studying 

 the habits of the salmon fly, which proved to be a stonefly, and which 

 has been identified by Mr. Nathan Banks, formerly of the Bureau of 

 Entomology, as Taeniopteryx pacifica. 



' Smith, Lucy W. the biology op perla immargin.\ta say. In Ann. Ent. Soc. Amer., v. 6, no. a, 

 p. 203-212, illus., pi. 23. 1913. 

 ' Smith, John B. insects of new jersby. Jn Ann. Rpt. N. J. State Mus., 1909, p. 15-880, illus. 1910. 



Journal of Agricultural Research. Vol. XIII, No. i 



Washington, D. C. Apr. i, 1918 



ma Key No. K. 6a 



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