48 



Corn as a Trap Crop for the Boll Worm. 



My mind is made up now concerning the protection afforded tomatoes by corn. 

 My tomatoes suffered badly during the presence of second broods of worms in June. 

 No silks in corn 200 yards away. Third brood of worms plentiful in corn in silk; 

 no worms in tomatoes in same patch. At a neighbor's farm, a second brood of worms 

 ate or bored into at least 50 per cent of tomatoes; corn not in silk. Third brood 

 plentiful in corn when in silk ; no worms in tomatoes in same patch. The above 

 verifies observations of last season, though my object then was to test preference 

 for host plants then in my garden. Will say that at other gardens, not referred to 

 above, have found conditions as mentioned, and I am perfectly satisfied that any 

 tomato crop can be protected by judicious use of corn, by crushing the first brood 

 in the tops of corn early in and throughout May, or by planting an extra early vari- 

 ety of corn that will be in silk by the 1st of June. * '<^ ^^ The fourth brood of 

 worms will be at work about August 15 in trap corn that is planted for protection of 

 cotton, and which, I am certain, will prove satisfactory in every instance tried. I 

 fully indorse the report of your able field agent, Mr. Mally, on every practical point, 

 and would emphasize all he says in the strongest terms concerning corn as a trap for 

 the worms — plantings adapted to the appearance of the different broods ; in fact, I 

 believe it to be the only sure and certain way to protect a cotton crop. Poisons 

 should be abandoned, for reasons set forth on page 53, Bulletin 26, of your Division. 

 Tried them thoroughly last season. Lights are a failure, as proved under all circum- 

 stances, and, as I conceive, our only hope is trapping in corn, colonizing the worms, 

 and centralizing natural enemies. — [S. B. Mullen, Mississippi, July 18, 1892.] 



Silk Gut from native Silk-worms. 



I am endeavoring to breed the larvse of Attacus cecro;pia, A. polyphemus, and A. lima, 

 with a view to obtaining silk gut stronger and longer than that at present furnished 

 to anglers by that of the Sericaria mori. I have already a good supply of eggs await- 

 ing development, and if you could give me any hint as to food or method of keeping 

 and rearing I shall esteem it a great favor. — [John Harrington Keene, New York, 

 June 27, 1892.] 



Reply. — * * * You will have little difficulty in rearing the larvsB if you inclose 

 them upon a branch of the tree upon which they naturally feed. Use a very large 

 mosquito-netting bag for this purpose, and watch it carefully to see that no holes 

 are worn into it through which a bird could get entrance. The cecropia can be 

 reared to the best advantage upon Apple, the imlyphemus upon Elm, Maple, or Wil- 

 low, and the Imia upon Beech, Butternut, Birch, or Liquidambar. The Department 

 has never furnished eggs of any insect except the Silk-worm of commerce, and since 

 July, 1891, has not been able to furnish even these, since Congress has abolished the 

 work of the silk section. I shall be glad to learn the results of your experiments. — 

 [June 28, 1892.] 



Corn Stalk-borer in Virginia. 



Accompanying this are some stalks of corn badly eaten by worms. These are 

 some of the worst specimens, but whole fields are attacked. Please give me your 

 best method of counteracting them, or of preventing their depredations. They 

 seem to be increasing every year, and with dry or unfavorable weather they may 

 destroy the corn crop. With fine growing weather the corn seems to be strong 

 enough to overcome their effects in a measure. — [P. C. Waring, Virginia, June 23, 

 1892. 



Eeply. — The insect which is damaging your corn is the Larger Corn Stalk-borer 

 (Diatrwa saccliaralis). This species has been treated in Nos. 3 and 4, volume iv, 

 Insect Life, where you will find all the information we have to give. If, after read- 

 ing this article, you have any additional facts to convey, the Entomologist will be 

 very glad to receive them.— [June 28, 1892.] 



