146 



INSECTS INJURIOUS TO VEGETABLES 



FLEA-BEETLES AND LEAF-BEETLES 



An unusual number of flea-beetles are reckoned among 

 enemies of cruciferous crops. No less than seven species (of 

 Pliyllolreta) are more or less attached to this class of plants 

 and although like other flea-beetles they are as a rule only 

 periodically troublesome, they are in their abundant seasons 

 foes of no little importance. The characteristics of flea-beetles 

 have been described on page 63. The cabbage-feeding forms 

 are mostly quite minute, none measuring more than an eighth 

 of an inch. 



The Striped Turnip Flea-beetle {Phyllotreta vittata Fab.). — 

 The commonest and most destructive flea-beetle living on 



cruciferous crops is the species 

 ahdve mentioned. It is found 

 throughout the warmer months, 

 and attacks most crucifers, cul- 

 tivated and wild. As it is sub- 

 ject to great fluctuation in num- 

 bers, it cannot be compared to 

 the imported cabbage looper or 

 harlequin bug, yet it is capable 

 of severe injuries and crucifer- 

 ous crops are seldom free from 

 it within its range, which is 

 extensive. The beetle (fig. 97, 

 b) is polished black in color, 

 and each wing-cover is ornamented with a broad, wavy band 

 of pale yellow. 



This species is indigenous to the Atlantic region, where it is 

 most abundant, but has been diffused by commerce, until now 

 it is found in most States and Territories from Maine to the 

 Gulf and Pacific States. 



Remedies. — When cabbage and other crucifers are treated 

 with arsenicals for "worms" no further remedy is necessary 



I 



Fig. 97- — Striped turnip beetle, a. larva; 

 b. beetle. (Riley, U. S. Dept. Agr.) 



