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AN ECONOMIC ENTOMOLOGY. 



fields, being by no means nice in their choice, and only requiring 

 that it be juicy and that there be plenty of it. They become 

 about half-grown before winter sets in, and hibernate among the 

 roots of the plants upon which they have been feeding, or under 

 stones, logs, or other cover. In this condition they remain until 

 the spring following, and then manifest quite a variety of habits. 

 In orchards some of the species develop a climbing tendency, 

 and make their way upon trees or shrubs to cut off the young- 

 shoots and buds. These have been termed ' ' climbing cut- 

 worms,'' but as a matter of fact a number of species develop 

 this habit when the larvae are in the proper location. Where 

 there is an abundance of low plants, these are eaten off at about 

 the surface of the ground, and the cut-worms fill themselves 

 until they seem almost ready to burst with the juicy tissue. 

 Where sod land has become badly infested by them, and is 

 ploughed and planted in spring, very frequently everything is 

 eaten off as fast as it shows above the surface. In some cases, 

 where they are very numerous, it is absolutely impossible to 

 obtain a stand of corn, and the crop must be abandoned in favor 

 of some other which the insects do not attack, although this 

 apparent exemption is frequently due to the fact that the insects 

 have wandered off, or have become full-grown and changed to 

 pupae. This change usually occurs some time during the latter 

 part of June, or in July, and little complaint of injury from cut- 

 worms is heard after that period. The moths do not make their 

 appearance until late in August or September, and lay their eggs 

 during the latter month. Some species are double-brooded, and 

 may be found even later than this, until November or even 

 December. This, be it understood, is only a very generalized 

 history of one group, and is not intended to apply even to all of 

 the genera whose larvae are cut-worms ; but for all practical pur- 

 poses the injurious species may be assumed to have habits 

 similar to those just described. The reason cut-worms are so 

 injurious is that the abundance of plants in an overgrown field 

 where the eggs are laid is replaced by a very small quantity set 

 out by the farmer for his purposes. The result is that the cut- 

 worms, comparatively moderate in number in the first place, 

 become exceedingly plentiful, and destroy the cultivated plants 

 about as fast as they make their appearance or are set out. In 



