4 FARMERS BULLETIN 860. 



FOLIAGE-ATTACKING INSECTS. 



BLACKHEAD FIREWORM.' 



Three distinct species of the so-called fireworms — the blackhead, 

 the yellowhead, and the red striped — are loiown to infest cranberry 

 vines. Of these the blackhead fireworm is by far the most injurious. 

 Tt causes very large losses annually in Ncav Jersey and is well known 

 for its destructiveness in Massachusetts, Wisconsin, Long Island, 

 and the Pacific NortliAvest. 



Characteu of Injury. 



Injury produced by the three species of fireworms is very similar, 

 but inspection of the webbed foliage soon will reveal the worms, 

 disclosing whether the blackhead or one of the other kinds is at work, 

 the distinction being indicated by the terms used as their common 

 names. 



Blackhead fireworms feed on various parts of the plant at different 

 periods in their development, the total damage in cases of severe 

 infestation finally giving to the vines a burnt appearance, which 

 justifies the term "fireworms." The young worm, or larva, of the 



first b r o o d usually 

 burrows into the lower 

 side of one of the 

 lower leaves and for 

 several days acts as a 

 leaf m,iner (see fig. 1), 

 after which it crawls 

 to the tip of the up- 

 right and either bores 

 into the unopened 

 bud or makes a web, 

 joining one or more 

 < > I' the terminal leaves 

 to the bud, beneath 

 which it feeds. As 

 soon as new shoots of 

 the vines are forced 

 out the worm attacks 

 the young leaves, 

 welibing the topmost 

 together (fig. 2), so 



1 .—Blackhead liivworiii : Frass or castings over miucs '^ . • T -t- 



(if newly hatched larvse in cranberry leaves. that in itS feeding it 



RJiopobota r(iccihia)ia Puck. 



