124 ''f'HE POTATO 



mixture ; hence, the only known means of reducing 

 their ravages is to spray the plants with this material. 



NUMBER OF FLEA-BEETLE PUNCTURES IN 50 LEAFLETS FROM 

 12 ADJACENT ROWS ' 



Punclures 



Row I. — Spraj-ed with very weak Bordeaux mixture . 1,794 

 Row 2. — Sprayed with very weak Bordeaux mixture and 



soap 1,071 



Row 3. — Not Sprayed 2,511 



Row 4. — Sprayed with strong Bordeaux mixture . . 1,194 

 Row 5. — Sprayed with strong Bordeaux mixture and 



soap 1.090 



Row 6. — Sprayed with weak Bordeaux mixture . . . 1,295 



Row 7. — Sprayed with weak Bordeaux mixture and soap 901 



Row 8. — Not sprayed 2,287 



The grubs of the flea-beetle infest the tubers and 

 roots of potatoes, doing some damage and causing the 

 trouble known as "pimply potatoes.'"* 



In the Pacific Coast the flea-beetles {Epitrix subcri- 

 7iita, Lee, and E. hirtipcnnis, Mels.) sometimes reduce 

 the yield 50 per cent, by their ravages. As they are 

 leaf-eaters, the foliage should be sprayed or dusted with 

 an arsenical poison. One pound of Paris green to 150 

 gallons of water per acre is suggested,' but it is better 

 to apply the Paris green in Bordeaux mixture. 



The Potato Beetle, Colorado Potato Beetle, 

 OR Potato Bug {Doryphora decern lineata). — Until 1850 

 this insedt was confined to Mexico and the Rockies. 

 In 1859 its eastward movement was noted, and it is 

 now well distributed. A related species {D. Juncta) 



» Vt. Bui. 72, pp. 6-9. * (N. Y.) Geneva Bui. 113, pp. 312-317. 



» Cal. Bui. 135, p. 29. 



