CAPE COD CRANBERRY INSECTS 39 



seem never to harm dry lioiits much. Tliey attack mostly l)ogs flowed during 

 the winter and not reflooded much m June. If they are once thoroughly elim- 

 inated from a bog, their presence in destructive alumdance need not be feared 

 again for several years. Extensive outbreaks of the two species probably 

 have occurred nearly sinudtaneously and after marked general reductions of 

 the black-headed fireworm, for the June reflooding and the lead arsenate 

 spraying formerly generally practised to control the fireworm check these 

 worms also. They are likely to be more prevalent than heretofore because the 

 nicotine sulfate spray that has displaced lead arsenate as a fireworm treatment 

 does not harm them nuich. i 



Growers should know the moths of these two species, for their abundance 

 indicates coming trouble. 



Green Cranberry Spanworm.^' 



This species occurs in limited numiiers on most Cape Cod bogs every| year 

 and sometimes does extensive harm. It broke out on many bogs in 1920 and 

 1921, destroying the entire crop promise on a considerable acreage. Growers 

 of long experience said it had l)een similarly prevalent for a time some twenty 

 years lief ore. 



iJixfrihitlion mid Food Phaifa. 



The moth has been found in Massachusetts, New York, New Jersey, Wis- 

 consin and Vancouver Island. No food plant besides cranberry is known. 



Chffrarter of Injunj. 



When the winter flowage is held till mid- or late May, some of the worms 

 hatch in time to eat into terminal Inids like false armyworms (fig. 22). They 

 seldom do much harm in this way. They usually work like the blossom worm, 

 nipping oif flower buds and blossoms by severing the stem near where it joins 

 the ovary (fig. 28). When extremely abundant they attack the leaves and 

 sometimes brown a small area. 



Description and Seasonal Hisfori/. 

 The Efig. 



There is one brood a year. In late June, July and early August the female 

 moths scatter their eggs singly among the litter under the vines, laying about 

 125 each. They usually stick to fallen leaves or pieces of dead twigs (fig. 29). 

 They are greenish white, elliptical, and almut a thirty-seventh of an inch long. 

 They are surprisingly rigid and unyielding as they come from the moth's body 

 and, when examined with a microscope, are seen to lie thickly studded, ex- 

 cept more or less on a central area ai)Ove and below, with minute shiny round 

 smooth white tubercles (fig. 30). They often become somewhat sunken in the 

 middle as hatching approaches. The winter flood does not harm them even 



45. Itame sitlphurea (Pack.). Heretofore known in cranberry literature as Cymatophora sul- 

 phur ea. 



