28 MASS. EXPERIMENT STATION BULLETIN 239 



if ])(),ssihle. This kills the moths and jirohahly any i)upae that remain. This 

 treatment has oth.er a chantages. (See ]). .58). 



The flooding late in May advocated for control of the fivpsy moth will de- 

 .stroy this pest if the winter water has been let off in April; and the floodinf>- 

 in June for the hlack-headed fireworm checks it anyway. 



SprtniiDji. 



A spray of (i jiounds of dry lead arsenate in 100 gallons of water is ef- 

 fective if aj>])lied before the v.orms are half-grown. Tiiey grow harder to 

 poison as tiiey I'latiire. 



BaUiiKi. 



See page 26. 



Spotted Cutworm." 



Tliis insect lias been V.nown to injure occasionally small areas of bog on 

 Cape Cod for over twelve years but has not been reported as a cranberry 

 pest elsewhere. There was a marked outbreak in 1923, two hundred acres or 

 more of bog in \arious parts of the Cape being so infested as to lose most of 

 the prosjiective crop, and a few of the worms and scattering marks of their 

 work being found on most bogs. 



I>i,'^trihution (iikI Faod l^'ants. 



This cutworm was brought into our country from Eurasia many years ago 

 and now ranges from New England to southern Missouri and the Pacific coast 

 of Oregon and Washington. 



It is a very pernicious pest of vegetable and forage crops. The following- 

 are some of its food plants: beet, cabbage, celery, chicory, chickweed, clover, 

 corn, cranberry, currant, fern, goldenrod, grass, Helianthus, lettuce. Lobelia, 

 maple, onion, jiear, rhubarb, spinach, strawi)erry, tobacco, tomato, violet and 

 wheat. 



Character of Injur;/. 



In 1923, this insect did much harm on a few acres of one bog bared of its 

 winter flood in April. With this exception, it has been known to attack severe- 

 ly only bogs drained of the winter water between May 26 and June S. It 

 generally works more on Howes vines than on Early Black. The worms work 

 almost entirely at night. They n^^ off the blossom buds, flowers and small 

 berries, severing the stem near where it joins the ovary (fig. 26), being most 

 active during the blooming. They also excavate partly grown berries (fig. 

 27) nnich as katydids do, and cut oft' luany leaves by severing the petiole, ap- 

 parently eating little of the tissue. The fallen green leaves are seen first in 

 and along the Itog ditches and later everywhere under nuich infested vines. 

 Severe infestations sometimes so defoliate small areas that the bare uprights 

 ifive the vines a brown tinge at a distance. 



37. Agroiis c-nigrum (L.). 



