92 SOME INSECTS INJURIOUS TO TRUCK CROPS. 



6. Piper, C. Y.— Biil, 17, Wash. State Agr. Exp. Sta., pp. 55, 5G, 1895. 



Short senoral account, with list of food plants. Species stated to be " by far the 

 most destructive flea-beetle in the State" [of Washington]. 



7. Chittenden, F. H.— Bui. 9. n. s., Div. Ent, U. S. Dept. Agr., p. 22, 1897. 



Short note on abundant occurrence on rhubarb near Washington, D. C. 



8. DOANE, R. W.— Bill. 42, Wash. Agr. Exp. Sta.. pp. 11, 12, figs. 2, 3, 1900, 



A 2-page general account with two original illustrations. 



9. Forbes and Hart.— Bnl. 60, Univ. 111. Agr. Exp, Sta., p. 472, 1900; 21st 



Rept, State Eut, Ills., p. 124. 



A brief account ; on sugar beet in Illinois. 



10. Fletcher, Jas. — Rept. Entom. and Bot. Canada for 1903 (1904). p, 177. 



Mere mention as affecting hops at Sardis, B. C, in noticeable numbers. 



11. Fletcher, Jas,— Rept. Entom. and Bot. Canada for 1906 (1907), p, 215, 



Account of injuries in the Eraser River Valley, B. C. in lOOG, with quotations 

 from John Wilson, Agassiz ; Thos. Cunningham, Vancouver ; and H. Ilulbert, Sardis, 

 B. C, which include experiences with remedies, 



12. QuAYLE, H. J,— Journ, Econ. Ent,. Yol. I, p. 325, October, 190S. 



A short article, with notes of injury In British Columbia ; account of habits, all 

 stages, Including the egg, being taken 8 to 6 inches from the surface of the ground, 

 larvae feeding at the roots of hop and other plants growing in the yards ; list of 

 food plants, and difHculties of applying remedies, 



SUMMARY. 



The hop flea-beetle, a minute, black insect, feeds on various succU'- 

 lent plants. It does serious damage to hops in British Columbia and 

 less injury to sugar beet and vegetable crops in the Pacific coast 

 region. 



Its life history is only partially known, but all stages have been 

 found about the roots of hops and the larva probably feeds on most 

 of the same plants as the adult. It is feared that this species may 

 become an important hop-pest in "Washington and Oregon, and it 

 doubtless does more injury to beets than is generally accredited to it. 

 Injury is most severe to young plants, but on sugar beet the operations 

 of the beetles throughout the season undoubtedly have a deleterious 

 effect and necessarily decrease the yield. 



The abundance of the beetles when they appear early in the season 

 on young plants, their constant reappearance, and the constant new 

 growth of the plants from day to day make it difficult to apply 

 direct remedies with more than temporary benefit. "\Miere the hops 

 are sprayed with kerosene emulsion or whale-oil soap for the hop 

 aphis the numbers of the beetles are lessened. Among measures 

 which give promise of value are the institution of clean methods of 

 cultivation, including deep fall plowing, treating hop poles in such 

 manner as to prevent the beetles from hibernating in them, and clear- 

 ing all remnants from fields so as to leave them as bare as possible to 

 prevent the beetles from sheltering there in winter. Arsenate of lead, 

 Paris green, kerosene emulsion, whale-oil soap, and Bordeaux mixture 

 should receive further tests, as should the employment of trap crops 

 in the manner advised in this article. 



