228 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



the numbers of aphids and in most cases will be the only treat- 

 ment necessary. 



The corn root-aphis is also recognized as a pest of cotton, 

 especially the young plants. When it appears it may be 

 controlled to some extent by frequent shallow cultivation of the 

 young plants until they are well established. Infestation may be 

 avoided by a system of rotation where cotton does not follow 

 either cotton or corn in infested fields.* 



The Cotton Worm f 



Until the advent of the boll weevil, the cotton worm was 

 much the most serious insect pest of cotton. Since then, however, 



FIG. 192. Pimpla conquisitor, one of the principal parasites of the cotton- 

 caterpillar: a, larvae enlarged; 6, head of same still more enlarged; c, pupa; 

 d, adult female enlarged; e, /, end of abdomen of adult male, still more 

 enlarged. (From Fourth Rept. U. S. Entom. Comm.) i 



its importance has been rather overshadowed in the mind of the 

 planter by the onslaught of the invading Mexican pest and where 

 the boll weevil is abundant the stripping of the late foliage by 

 the cotton worm really aids in the control of the weevil, as will 

 be explained later. 



Life History. -During the winter months the adult moth 

 hibernates in the most southern portion of the cotton-belt, in the 

 rank wire-grass occurring in the more thickly timbered regions. 



* See W. A. Thomas, S. C. Expt. Sta. Bulletin 175. 



t Alabama argillacea Hubn. Family Noctuidce. See W. E. Hinds, Bul- 

 letin 164, Alabama Agr. Expt. Station. 



