56 



FARMERS BULLETIN 856. 



near the liocky Mountains. It abounds from Xew England and 

 Canada to Florida, westward to Texas, and in the northern Pacific 

 region, where it has become troublesome only recently. Both the 

 "slugs" (the young, or larva?) and the beetles (adults) feed upon the 

 potato plants. After passing the winter in the ground, the beetles 

 usually appear at about the same time as the potato plants, lay their 

 eggs, and continue feeding. They often destroy small areas, espe- 

 cially those grown for garden purposes. When the " slugs " of the first 

 crop begin their work they usually finish up that begun by the over- 

 Avintered beetles, leaving only bare stems, Avhieh become dry and 

 black. After exhausting the potato, the beetles attack eggplant and 

 other plants of the potato family, including tomato, ground cherry, 

 jimson Aveed, and related weeds. In the most northern range of this 

 insect there is probably only one generation a year, but two genera- 

 tions and a partial third occur southward. 



Fig. 1)3. — The potato tuber ninth (Phthorimuca opcrculcUa) : a, Larva, or 

 from above ; b, moth with wings expanded ; c, pupa. Much enlarged. 



worm, seen 

 (Graf.) 



Control. — Ducks, guineas, and other domestic fowls eat the beetles 

 and larvse. So also do snakes, toads, and skunks, which frequently 

 gorge on them. Arsenate of lead is the best remedy, applied as ad- 

 vised on page 9. 



BLISTKK BEETLES. 



Blister beetles are next in importance to the Colorado potato 

 beetle as potato insects. They are slender, somewhat soft bodied, 

 of various colors, and feed upon all forms of garden truck, appear- 

 ing to prefer potatoes, following with beans, peas, and related crops, 

 beets, cabbages, squashes, and others. When occurring on the potato, 

 they are sometimes called the " old-fashioned potato bugs." 



Control. — Lead arsenate is the best remedy, prepared and applied 

 as directed for the Colorado potato beetle, but driving and burning 

 also are useful. See " Blister beetles " (p. 17). 



THE POTATO TUBER MOTH. 



The larva, or " Avorm," of a small gray moth, the potato tuber moth 

 (fig. 63), is the Avorst potato nest known in California, (See fig. 64.) 



a 



