3i8 



MISSOURI AGRICULTURAL REPORT. 



a corn or wheat field at this time the amount of damage they will do 



cannot be appreciated by any one who has not actually seen their work. 



Two acres of corn or wheat will disappear down the throats of an 



ordinary army of these worms each day. 



Soon after the adults have emerged, they pair and lay eggs for 



another brood. These eggs are deposited in the same situations as were 



those for the first brood. If 

 conditions are favorable for the 

 development of the army- 

 worms, this second brood of 

 larvae coming from these eggs 

 will be several hundred times 

 more numerous than were the 

 larvae of the first brood, and it 

 frequently happens that this 

 second brood is the one that 



\ 



\ 



does the most damage by 

 marching in armies and at- 

 tacking the corn at tliis season 

 of the year. The wheat plant 



Fig. 60. — Pupae of Army-Worm, Leucania . . . . 



unipuncta; a, a, natural size; the other two en- in AllSSOUn USUally eSCapCS tUlS 

 larged about three diameters. (From Slinger- 



land.) second brood, but the corn 



plant suffers severely. By referring to figure 56, you will observe a num- 

 ber of larvae photographed in the act of stripping a corn plant. These 

 insects are not quite natural size. 



In due course of time the larvae of this second brood enter the 

 ground in order to pupate, and the moths which hatch from this second 

 brood appear during the forepart of August. 



This second brood of moths again pair and lay eggs for a third 

 brood of worms, which appear in the central portion of Missouri usually 

 about the middle of August. It is not often that the migrating horde of 

 the third brood of army-worms do very much damage here in Missouri. 

 During the latter part of September or the forepart of October the third 

 brood of adults appear. These adults seek sheltered places later in the 

 fall, and there pass the winter hibernating as do the adults of the chinch 

 bugs. They seek, as a rule, the loose bark on trees, secluded places under 

 logs, and in piles of rubbish. We have no data to show that in central 

 Missouri, at least, the winter is ever passed in any other stage. I have 

 never been able to determine that the pupae ever fail to transform to 

 adults in the fall if they are going to transform at all, neither have I 

 been able to find that tlie larvae have ever failed to make pupae in time 



