10 



FARMERS BULLETIN 860. 



Fig. 6. — Yellowhoad fire- 

 worm : E a r 1 y - s c !i s o n 

 work of the larva> on 

 cranberry. 



control is an easy matter in most instances, 

 and its presence in considerable numbers on 

 a cranberry bog is usually an indication that 

 the bog was planned without sufficient regard 

 for i^roper flow age. 



Chakacteu of Injury. 



Injury resulting from the feeding of these 

 fireworms is similar to that of the blackheads, 

 causing the vines to appear as if fire swept. 

 The foliage is webbed in much the same 

 manner, permitting the worms to feed with 

 some protection. The vines shown in figure 6 

 are typical of the work of the early broods, 

 and those shown in figure 7 represent vine 

 appearance in September, at which time 

 much of the fruit is found wormy (fig. 8). 

 Crates of berries may be noticed in storage 

 houses late in September and during Octo- 

 ber that are infested with these worms, 

 which sometimes are mistaken for the true 

 cranberry fruitworm. 



DesCKIPTION AM) SEASONAL HISTORY. 



This species is peculiar in that the appear- 

 ance of the moth in summer is very different from that which it 

 assumes in the fall and winter. The moths that dcAxlop in the fall 

 are of a reddish gray color (fig. 9) and, notwithstanding the rigors 

 of the climate, pass the winter hidden among vines or brush or 

 sometimes in cranberry houses, although on warm, bright days they 

 may be seen on the wing. 



About April 1, egg laying begins, and the succeeding generations 

 of moths are orange red in color (fig. 10). The moths are a little 

 larger than the moths of the blackhead fireworm, and the same may 

 be said of the worms. The lighter color of the worm and its shining 

 yellow head serve readily to distinguish this pest from other fire- 

 worms. The eggs are yelloAv and under a lens will be found marked 

 off into irregular hexagonal figures. 



The pupa is dark brown to blackish, with a very prominent knob 

 at the head extremity. It may be found in a silken cell among 

 webbed uprights. 



During the course of some experiments carried on in New Jersey 

 in 1914, three generations of moths of the orange-red form were pro- 



