No. 4.] INJURIOUS INSECTS. 145 



industry, and that I was warranted in spending time and 

 money in investigating the insects which I was assured by 

 practical cranberry growers destroyed on an average one- 

 half of the crop on such bogs as could not be reflowed. I 

 am not able to say how correct this estimate may be, but I 

 have visited many a dry bog where no insecticide was used, 

 and where not a cranberry was raised. 



During the last seven years a large percentage of the 

 cranberry bogs in Barnstable, Bristol and Plymouth coun- 

 ties have been visited either by myself or one of my assist- 

 ants, and very careful studies have been made of the insects 

 attacking the cranberry. In this work we have found a 

 larger number than has generally been supposed to feed 

 on the cranberry, some of which are seriously injurious, 

 while others are not abundant enough to cause noticeable 

 injury, though they are liable at any time to increase in 

 numbers and become as destructive as those that are now 

 giving so much trouble, while still others are only oc- 

 casionally abundant in restricted localities, as the army 

 worm {Leucania unipuncta). There are three different 

 species that seem to cause the greater part of the damage 

 on the cranberry bogs in Massachusetts, so far as I have 

 been able to learn, and these are the vine worm, the fruit 

 worm and the cranberry span-worm. 



The Vine Worm. 



The vine worm, also known as the fire worm and black- 

 head \Iiliopobota vacciniana), is undoubtedly the most 

 destructive of all the cranberry insects occurring in this 

 State. This insect has two broods in a year. The moths 

 of the second brood fly about over the vines during the 

 middle of June or later, owing to the season or other cir- 

 cumstances, at which time they lay their minute, yellowish, 

 scale-like eggs on the underside of the leaves, where they 

 remain during the winter. The time of hatching in the 

 spring depends not only upon the season, but also upon the 

 time when the water is drawn off from the bog. If the 

 water is not drawn off till late, and the vines are not all 

 submerged, the eggs on the leaves above the surface of the 

 water will hatch, while those under the water will remain till 



