1. Egg'laying by the moths after late removal of floods allows the worms as 

 they hatch to find a very tender new cranberry growth, some such special food 

 probably favoring their survival. 



2. The moths seem to prefer to lay their eggs on or over damp earth. Bogs 

 drained during the flight of the moths therefore probably invite infestation. 



3. By breeding on freshly drained areas the insects may largely escape their 

 natural foes and so develop as they could not otherwise. 



The chances are even that some of these worms will infest a hog if the 

 winter flood is held till the end of May. Sometimes two species attack a bog tc 

 gether under such conditions, and occasionally one species is prevalent on some 

 bogs and another on others. They usually appear within ten days after the water 

 is let off. 



The various species of cutworms are hard to distinguish for a time after they 

 hatch, all being then mostly whitish or greenish, but they may be identified after 

 they are half-grown by the aid of the following table: 



With very conspicuous yellow stripes Zebra caterpiller^^. 



Not so colored _ 1 



1. Mostly dark, without definite sidestripes black cutworm (p. 31). 



With a conspicuous stripe along each side 2 



2. With a row of two to four angular dark spots on each side of the 



hind part of the back spotted cutworm (p. 28). 



Without such spots - 3 



3. The back reddish brown and not marked with pale yellow dots 



cranberry blossom worm (p. 27). 

 The back mostly dark, grayish, or green 4 



4. Found on a bog not bared of a long flood after May 20 



false armyworm (p. 24). 

 Found on a bog bared of a long flood after May 20 5 



5. With many small round or oval dark tubercles noticeable 



along the back _ fall armyworm (p. 34). 



The back without such tubercles 6 



6. With a broken pale line along the middle of the back armyworm (p. 32). 



A narrow dark'brown stripe along the middle of the back 



Atlantic cutworm^o. 



SPOTTED CUTWORM 

 Fig. 31. Spiracle of caterpillar. Much enlarged. 



1° Ceramica picta (Harr.). These worms (fig. K) often hatch in considerable -numbers 

 on cranberry bogs, but only a few ever mature there, cranberry apparently being an unfavor- 

 able food plant for them, and they never do much harm. They are noticed most in July. 



^° Polia atlantica Grote. This brown cutworm (fig. 'L) attacks cranberry bogs only 

 rarely and locally. See Mass. Agr, Expt. Sta. Bui. 355:39, 40, 1939; and Bui. 369:34, 1940, 



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