ANNUAL REPORT, 1936 37 



The females lay their eggs throughout September. They cover each egg 

 with a rough case made up of pellets of their dung deposited on it gradually as 

 it is laid. To do this, they hold the egg and case to the tip of their abdomen and 

 rotate them there slowly with their hind feet, supporting themselves meanwhile 

 with their two other pairs of legs. 



Most of the encased eggs are dropped on the sand under the vines but some 

 lodge among the vines and may be swept from them with an insect net. The 

 eggs themselves are oval, smooth, yellowish white, translucent, and about a 

 fortieth of an inch long. The cases are green at first but turn brown as they 

 dry. They are roughly oval and about a twenty-fifth of an inch long. 



This insect also attacks cranberry vines in New Jersey sometimes. It has 

 been taken in Framingham and Sherborn, Mass., and it ranges south to Florida 

 where it is abundant. It is found on wax myrtle 1 , huckleberry, and especially 

 fetter bush 2 . 



Cranberry Weevil (Anthonomus musculus Say). 



As it is considerable trouble to prepare the Bordeaux mixture-calcium arse- 

 nate-soap spray advocated as a treatment for this pest 3 , attempts were made 

 to find a more satisfactory insecticidal control. 



Kerosene applied as a spray at the rate of 100 gallons an acre, on June 11, 

 killed only a small percentage of the beetles. This treatment did very little 

 injury to the vines or crop, though the blossom buds were well developed when 

 it was applied. 



A hundred pounds of undiluted very high-grade pyrethrum dust (made from 

 flowers grown in Kenia and with a 1.6 percent pyrethrin content) an acre was 

 tried once and seemed to give a good kill. Fifty pounds of this dust per acre 

 was not effective. Pyrethrum has not controlled this insect heretofore. 



A hundred pounds of derris dust (1 percent rotenone) an acre, applied June 

 5, gave a poor kill. 



A spray of 8 pounds of derris powder (4 percent rotenone) and 4 pounds of 

 fish-oil soap in 100 gallons of water, used at the rate of 400 gallons an acre, 

 failed to give a good kill. 



Cranberry Flea-beetle (Systena frontalis Fab.). The only effective treatment 

 for this insect heretofore known was the Bordeaux mixture-calcium arsenate- 

 soap spray used to control the cranberry weevil (see above). Unfortunately, 

 only the flea-beetle adults can be treated with a spray. As they are active 

 from July till late September, an arsenical spray, to be effective, must be applied 

 at a time when it is likely to leave a residue on the berries. Moreover, the sea- 

 sonal history of the insect precludes a satisfactory control by flooding. Treat- 

 ments with other insecticides were therefore tried. 



A hundred pounds of undiluted high-grade pyrethrum dust (0.9 percent 

 pyrethrin content) an acre, applied August 13, was very effective in killing 

 the beetles. Fifty pounds of this dust to an acre gave only a fair kill. 



A spray of 10 pounds of derris powder (4 percent rotenone) and 1 pound of 

 Areskap in 100 gallons of water, applied at the rate of 400 gallons an acre on 

 August 11, also killed the beetles well. 



Cranberry Root Grub (Amphicoma vulpina). Many of the male beetles were 

 seen in flight on Beaton's Old Colony bog near South Yarmouth on July 17. 

 Several square rods of the bog showed much injury from the grubs. Grubs 

 were found in this area. The insect has never been found further east on the 



1 Myrica cerifera L. 



2 Lyonia nitida Bartr. 



'Mass. Agr. Expt. Sta. Bull. 239. p. 62, 1928. 



