486 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



given that will prove equally successful at all times and places. 

 Remedies that are very effective under ordinary conditions 

 often become wholly useless during a bad outbreak. Clean 

 cultivation will materially lessen the number of larvae that 

 occur in a garden under ordinary circumstances. When 

 the worms are abundant and marching, ditching is often re- 

 sorted to, usually with very satisfactory results. Banding 

 trees with tanglefoot or some similar substance is helpful in 

 case the cut-worms are of the climbing sort. A very few in a 

 garden may destroy many valuable plants, so it is often worth 

 while to search for them in the ground around the plants, and 

 destroy them. Poisoned baits may often be used with success. 

 When they suddenly appear in great numbers in a field but 

 little can be done to control them. 



The Corn Ear- worm (Heliothis obsoleta). This larva bores 

 unsightly irregular channels on the ears of corn, doing particular 

 damage to sweet corn. It is also a serious pest of cotton, feed- 

 ing in and destroying the bolls; hence it is also known as the 

 cotton boll-worm. Tomato fruit-worms and tobacco bud- 

 worms are among some of the other names that are applied 

 to this pest, which attacks almost all kinds of garden crops and 

 many forage plants. The greenish-yellow adult moths appear 

 early in the spring and lay their eggs on corn and other food 

 plants. The larvae feed about a month, and then enter the 

 ground to pupate. There may be from two to five or six broods 

 during the summer, the greatest number occurring in the south 

 where the feeding season is longer. 



In the garden about the only satisfactory means of control 

 is hand picking. It is seldom practicable to spray. In the 

 cornfield the time of planting should be so regulated that the 

 corn will not be in silk when the moths are flying most abun- 

 dantly. All infested land should be plowed late in the fall or 

 during the winter, as this will destroy many of the over-winter- 

 ing pupae. 



The Striped Cucumber-beetle (Diabrotica vittata). These 

 small, yellow, black-striped beetles attack many of the vines 

 in the garden as soon as they are above the ground, and as they 

 often occur in great numbers they may destroy most of the 



