ANNUAL REPORT, 1942 27 



with the surface between them very smooth, each ridge bearing a single row of 

 many short, sharp, tooth-like spines pointing obliquely backward. 



White Grub (Phyllophaga). Young grubs, evidently hatched in June, were 

 found rather abundant in a small area on the station bog on July 13, 1942. They 

 were quite active and all within an inch or two of the soil surface, most of them 

 within an inch of it. 



Cranberry Spittle Insect (Clastoptera). The young nymphs in their spittle were 

 found as early as June 2. Flooding a bog for 24 hours as soon as an occasional 

 flower had opened wiped out a heavy infestation completely without harm to 

 the vines or crop. This seems to be an excellent treatment. 



Cranberry Root Grub (Amphicoma). Half of the station bog was treated with 

 seven ounces of sodium cyanide in 100 gallons of water, a gallon to a square foot, 

 late in April and ver}' early in May. The treatment was very successful and did 

 not reduce the crop. It hurt the vines only on a few small areas. Flood water 

 drained from this bog eight days after the application had no poisonous effect. 



Army worms (Leucania) attacked freely several bogs that had been flooded 

 from mid-May to mid-Juh to control the root grub. 



Grape Anomala (Anomala lucicola Fab., formerly reported as Anomala errans). 

 Five acres of seriously infested bog, located in the Wenham section of Carver 

 and not heretofore known to be affected by this grub, were treated very success- 

 fully with sodium cyanide solution. 



Cranberry Tolerance of Certain Materiah. Long experience has found cran- 

 berry vines ver>- intolerant of sulfur but very tolerant of kerosene and fairly so 

 of copper. 



Cryolite, four tons to an acre, was applied to small areas of the station bog on 

 June 20, 1941. Injury- from this was \er\' slow in developing but had become 

 severe by July 1942. 



A mixture of 4 pounds of calomel and 96 pounds of talc, 100 pounds to an acre, 

 was dusted onto plots of Howes vines on July 1, 1941, with the vines then ap- 

 proaching full bloom. The set of fruit and size of berries were not much affected, 

 the crop turning out to be about as abundant as on the bog around the plots; 

 but the treatment greatly delated the ripening of the berries and they finally 

 failed to de\elop a good red color. The berries were picked toward the end of 

 September and were examined chemically and spectroscopically for mercury, but 

 none was found. The vines on these plots were not quite so green in the fall of 



1941 as those on the bog around them, and a rather noticeable number of scat- 

 tered branches died. The treated areas had a normal appearance during the 



1942 growing season, but they bore only about a third as much fruit as areas of 

 the same size around them. 



Prevalence of Cranberry Insects in 1942. 



1. Bumblebees and honeybees were abundant everywhere on Massachusetts 

 bogs during the cranberry flowering. 



2. Infestation by Gypsy Moth (Portketria) was light in Ph mouth County 

 and moderate on most of the outer Cape. 



3. Cranberry fruit worm (Mineola) was about normally abundant, more so 

 than in 1941. 



4. Black-headed fireworm was normally abundant, more so than in 1941. 



5. Firebeetle {Cryptocephalus) , almost none. 



6. Yellow-headed fireworm (Peronea) was more troublesome than usual in 

 recent vears. 



