40 The Bulletin. 



Life-history. — Briefly put, the life-history seems to be about as fol- 

 lows : The winter is believed to be passed mainly in the pupa stage an 

 inch or two below the surface of the ground. Moths emerging from 

 these in spring or early summer lay eggs from which a brood of worms 

 hatch. These, when grown, go underground and change to pupre, from 

 which another brood of moths emerges later. How many distinct broods 

 may thus be produced we do not know, but as the worms feed ravenously 

 and grow rapidly, there are certainly several broods, the later broods 

 (July to October — our records) being more likely to be destructive. 



REMEDIES. 



The outbreak of 1912 extended through many of the southern states 

 and called forth a special appropriation and special investigation by the 

 U. S. Department of Agriculture. In August, 1912, the TJ. S. Depart- 

 ment issued Circular No. 40 -(revised), upon which this account of 

 remedies is based. 



Poisoning the Worms. — In making applications of poison to kill the 

 worms, it must be remembered that the vegetation which is so treated 

 is not to be used as forage. Hence this method is more applicable to 

 waste places, or in the edges of cornfields rather than wholesale over 

 entire forage crops. Paris-green or arsenate of lead may be used, either 

 as a dust application or in water as a spray. As Paris-green is better 

 known and more available, we discuss it first, although the arsenate is 

 considered to be really more effective. 



Paris-green, Dry. — Mix Paris-green with lime or flour at rate of 1 lb. 

 to 4 lbs. of lime or flour. The worms eat it more readily if mixed with 

 flour, but it is less likely to hurt leaves if mixed with lime. Take your 

 choice. Dust the plants until whitened. 



Paris-green, Spray. — Mix Paris-green with water at rate of 10 ounces 

 to 50 gallons, adding 2 lbs. of freshly slaked lime. Spray liberally, en- 

 deavoring to reach all the leaves or blades of the plants treated. 



Arsenate of Lead, Dry. — This material is more commonly sold in 

 paste form, but the dry powdered form can be ordered, and is consid- 

 ered better than Paris-green because it can be dusted on pure without 

 injury to the leaves. It wull be cheaper to mix it with equal or twice its 

 weight of flour. 



Arsenate of Lead, Spray. — If the powdered form is to be used as a 

 spray, mix with water at rate of 2 lbs. to 50 gals, water. If the paste 

 form is to be used, use 4 lbs. to 50 gals, water ; spray thoroughly. 



Poison Bait. — -This method gives a chance to poison the worms with- 

 out applying it to plants at all, so the plants can be used as forage after- 

 wards. Mix 2 to 3 lbs. of either Paris-green or (powdered) arsenate of 

 lead with 100 lbs. wheat bran. Add 2 gals, syrup, and water enough to 

 moisten ; mix thoroughly, and distribute on ground where worms are. 



