90 INSECTS OF ECONOMIC IMPORTANCE 



California and durino- the past few years has heen 

 very destructive; it varies in color from pink to 

 green; the black winter e^^i^s are deposited on the 

 rose and other plants; in the spring- they hatch and 

 the aphids infest potatoes most seriously in July 

 and August; a generation developed about every 

 two wrecks; the potatoes wilt and finally die when 

 badly infested; in September the aphids desert the 

 potatoes and colonize on various weeds and par- 

 ticularly on the rose where the winter eggs are 

 again laid. 



Control — Clean culture with the destruction of 

 all host plants so far as possible; spray infested 

 plants with nicotine sulphate, ^ of a pint to lOO 

 gallons of water with 5 pounds of soap added. 



The potato stalk-borer (Trichobaris trinotata) 

 Order — Coleoptera 



This pest of the potato is more injurious in the 

 West apparently than here although it is often in- 

 jurious in New Jersey and may become so in New 

 York at any time. 



OTHER INSECTS INJURIOUS TO THE POTATO 



Egg plant flea-beetle (Epitrix fuscida). 

 Tobacco flea-beetle {Epitrix parvul a). 

 Potato tuber worm (Phthorimcua operculella). 

 Potato-scab gnat (Pnyxia scahici). 



SWEET POTATO 



The sweet potato flea-beetle^ (Chcetocnema 



confinis) 



Order — Coleoptera 



A small bronze or brassy-brown shining beetle 

 about one-sixteenth inch in length; hibernates over 



5 Smith— N. J. Expt. Stat., Rept. for 1908, p. 342. 



