and larvae are active except in the 

 coldest winter weather. This spe- 

 cies can live on dry vegetation when 

 no green food is available. 



Natural Control 



Under normal conditions cut- 

 worms are controlled by a highly 

 complex set of natural checks ; only 

 an occasional individual survives to 

 injure crops. When this natural 

 balance has been disturbed in some 

 way, cutworm outbreaks occur. 



Weather Conditions 



Weather conditions are especially 

 effective in the control of those 

 species that pass the winter as 

 pupae; heavy autumn rains may 

 cause an unusually high mortality 

 in this group, so that these species 

 may be scarce the following spring. 

 Heavy rains also may kill large 

 numbers of active cutworms by 

 drowning or burying them. Some 

 cutworm species are not able to 

 withstand much cold, and are found 

 only in southern States. Very cold 

 weather and abrupt changes in tem- 

 perature kill large numbers of all 

 species of cutworms. 



Parasites and Diseases 



Many insect parasites and a num- 

 ber of diseases attack cutworms. 

 You may never see them at work, 

 but without them cutworm out- 

 breaks would occur more often. 



Predatory Enemies 



Predatory insects and spiders 

 help reduce the numbers of cut- 

 worms. Birds also are effective in 

 cutworm control. During May. 

 cutworms and similar larvae make 

 up more than 20 percent of the aver- 

 age diet of such common species as 

 the chipping sparrow, cardinal, 

 meadowlark, robin, redwing black- 

 bird, bluebird, bobolink, Carolina 



Adult of dingy cutworm. 



BN-3516 



Eggs of the variegated cutworm moth. 



wren, bobwhite, and crow 

 also destroy cutworms. 



Toads 



Control Measures 



Plowing the Soil 



Plowing or cultivating land be- 

 fore using it as a tobacco plant bed 

 or tobacco field may reduce the num- 

 ber of cutworms in the soil. The 

 effects of this practice will vary 

 with the locality, the species of cut- 

 worm present, and the time cultiva- 

 tion is carried out. Fall plowing 

 breaks many of the cells in which 

 some species pass the winter as pu- 

 pae, and pupae in these broken cells 

 die. In northern areas, late fall 

 plowing is not effective against 



