38 THE CANADIAN ENTOMOLOGIST 



HYPERA NIGRIROSTRIS FAB. IN THE PACIFIC NORTHWEST.* 



BY L. P. ROCKWOOD, 

 U. S. Department of Agriculture, Bureau of Entomolog}', Forest Grove, Oregon. 



Hypera (Phylonomus) nigrirostris Fab., is a clover insect of supposedly 

 European origin^ which, for many years, has been known to occur in the eastern 

 states and eastern Canada. It has been recorded from as far west as Minnesota 

 by Schwarz,^ the most western point of which I have seen record, except as 

 hereinafter stated. The insect is a very close relative of the Alfalfa Weevil, 

 Hypera posfica, and the discovery of its parasites in northwestern America is, 

 therefore, thought w'orthy of record. 



In 1916 Professor R. A. Cooley^ reported this weevil from "one valley in 

 western Montana," where the insect had been present "during the past two 

 years." In May, 1915, the author found adults of H. nigrirostris at Bellevue, 

 Wash., on the shore of Lake Washington opposite Seattle. The distribution 

 of this insect in the Pacific Northwest has since been traced by members of the 

 staff of the Forest Grove Laboratory of the U. S. Bureau of Entomology, Cereal 

 and Forage Insect Investigations as follows: — H. nigrirostris was found in 

 western Montana by C. W. Creel at various points in the Flathead Valley from 

 Columbia Falls on the Great Northern Railroad to Dixon on the Northern 

 Pacific Railroad, and also at Arlee, Montana, in the Jocko Valley, a short dis- 

 tance south and east of the Flathead Valley. West of the Cascade Mountains 

 it has been found from \^ancouver, B.C., on the north (by C. W. Creel) south- 

 ward through Washington to its southern limits in Oregon at Garden Home 

 in the Willamette \^alley. Forest Grove, in the Tualatin \'^alley and Nehalem 

 on the coast. Mr. Wm. T. Ham, of the Truck Crop Insect Investigations of 

 the U. S. Bureau of Entomology, reports it in correspondence from Orcas Island, 

 Wash., and Longmire's Springs on Mt. Rainier at an elevation of 2,761 ft. 



In 1915 and 1916 //. nigrirostris was found in fair numbers at Bellevue- 

 Wash, and Olympia, Wash. In 1917 this species was very numerous and doing 

 considerable damager to clover on the grounds of the Western Washington 

 Experiment Station at Puyallup. In the season of 1918 H. nigrirostris was 

 discovered for the first time at Forest Grove, Oregon. Only three specimens 

 were found in that locality during the entire season of 1918. It does not seem 

 possible that this insect could have been present at Forest Grove prior to this 

 year, as clover fields of the vicinity had been very carefully watched since 1914. 

 In the season of 1919 the weevils were slightly more plentiful at Forest Grove, 

 but still by no means common. The insects increased in numbers toward the 

 north, that is toward the Columbia River and the Coast Range, beyond which 

 they also occurred on the ocean front near Nehalem, Oregon. Every indica- 

 tion is that the trend of dispersion of the species is from the north to the south. 

 There is, however, an unusual phenomenon concomitant to this invasion 

 of a new region by a well-known insect. It was stated above that but three 

 specimens of H. nigrirostris were found at Forest Grove in 1918. One of these 



*Published by permission of the Secretary of Agriculture. 



1. Webster, F.M., U.S. Bureau of Entomology, Bulletin 85, Part 1, 1909. 



2. Schwarz, E. A., Proc. Ent. Soc. Wash., Vol. 9, 1908, p. 114. 



3. Cooley, R. A., 14th Annua! Rept. Sta. Entomologist Montana, Hull. Xo. 112, j). 07, 

 1916. 



February. 1920 



