THE ARMY WOBM IN CBANBEBBY HOGS. 13 



Department of Agrh ulture, 

 Entomological Division, 



July 7, 1682 

 Mr. CHA8. G. BoCKWOODj XeuarJc,X.J.: 



Dear Sir: Iu regard to the saw-fly yon sent me as injurious to cranberries, I will 

 say that in my breeding jars they refuse to eat the cranberry plants. It now occurs 

 to me that you may have possibly overlooked the real authors of the mischief, and 

 that the saw-fly larva? have merely fallen upon the cranberry plants from some other 

 plant. I beg you now to ascertain whether the larv* really feed on the cranberries. 

 By doing so you will greatly oblige. 

 Yours, truly, 



C. V. RILEY, 



En lomologist. 



Newark, N. J., July 10. 

 C. V. Riley, Esq., Entomologist: 



Dear Sir : Your favor of the 7th instant has beeu received. There is no doubt that 

 the worm of which I sent you the young did the mischief by eating the vines. I sup- 

 pose that my farmer happened to put in the box only old cranberry vines. They do 

 not touch the old vines, but eat the young shoots off this year's tender growth, and 

 only after exhausting the supply of grass which grows among the vines. But eating 

 the new growth takes the fruit buds and destroys this year's crop, and takes also the 

 growth which is to bear next year. The worms undoubtedly feed upon the vines. They 

 leave upon the ground many leaves, but must consume largely. 



"When I was there, in spots not reached by the worms the new growth arose solid 

 above the old vines, say, 4 inches, so that nothing else could be seen. On the other 

 side of the ditch would be a patch eaten clean down to the old vines, leaving them as 

 they were when the water was taken off and before new growth has started, and the 

 whole patch 4 or 5 inches lower in solid growth than the untouched patch adjoining, 

 and of different color. 

 Respectfully, 



CHAS. G. ROCKTVOOD. 



YVe visited Mr. Rockwood, at Xewark, X. J., shortly after the receipt 

 of his last letter, and concluded from further information obtained that 

 the saw-fly larva 1 were certainly not the authors of the mischief, but 

 that the Army Worm in all probability did the damage. Yet, as doubt 

 remained, we were anxious to settle the question, and sent Mr. E. A. 

 Schwarz to make examination on the spot. The following is the report 

 of his observations : 



Sir : In accordance with your directions I have made a study of the injury done to 

 Mr. Rockwood's cranberries as far as it was possible at the time, the insect that did 

 the damage having disappeared more than six weeks previous to my visit at Ham- 

 monton. 



The Rockwood cranberry farm is divided into squares, each of about 50 acres, sur- 

 rounded by high dikes, and intersected by numerous irrigation ditches. Two or three 

 other squares are just being constructed, but are not yet inclosed with dikes. The 

 cranberries being fully formed at the time of my visit. August 1. there was no diffi- 

 culty in taking in at a glance from the high dikes tli«' extent of the damage done by 

 the insect. It was apparent that the damage was confined to a number oi the BmaJlei 

 squares formed by the irrigation ditches. On some of these hardly any berries were 

 to be seen, while other squares adjoining the damaged ones, and only separated from 

 these by the narrow ditch, were not injured at all. On the newly constructed squares, 

 where there is an abundance of grass, the newly-planted vines had severely Buffered. 



