16 



FARMERS BULLETIN 860. 



last brood descend to 

 the ground to form their 

 cocoons and remain 

 there until the follow- 

 ing spring. Thus hiber- 

 nation occurs on the 

 bog and is not affected 

 appreciably by ' o r d i - 

 nary holding of the 

 Avinter flowage. The hi- 

 bernating cocoon is a 

 very small, av h i t i s h , 

 flattened oval case of 

 closely spun silk and 

 usually will be 

 found attached to a 

 fallen leaf or bit of 

 trash, but also may be 

 found fastened to a 

 woody stem a few inches 

 above the ground. The 

 cocoons of the first 

 brood of worms appear- 

 ing in the spring occur in the damaged leaves at the tips of uprights 

 or runners. 



In the late spring the orange-red or yellowish grub (fig. 15) 

 changes into a brown pupa and shortly before the time for the fly 

 to emerge the pupa works its way out of the cocoon through a slit 

 at one end. The adult is a very delicate, two-winged fly whose 

 extended wings measure not more than an eight of an inch from tip 

 to tip. (Fig. 16). 



The eggs are colorless, very slender, slightly curved, almost micro- 

 scopic, and have been seen to be deposited on leaf surfaces at the tips 

 of the uprights. 



Two generations are known in Massachusetts, and present informa- 

 tion indicates that in New Jersey the insect is commonly of two 

 generations, although a partial third perhaps may develop upon bogs 

 from which the Avinter flowage is draAvn early. 



Treatment. 



Fig. 14. — Cranberry tipworm : 

 tipwon 



Tips of uprights killed by 



Extensive observations made on certain Massachusetts bogs, by 

 Dr. H. J. Franklin, have shown that infestations may be reduced to 

 a minimum by sanding the bog lightly every other year. Bog con- 



