32 a EXPERIMENT STATION. [Jan. 



REPORT OF THE CRANBERRY STATION. 



H. J. FRANKLIN. 



Investigational Work. 



Insects. — The study of cranberry insect problems in general 

 was continued. In co-operation with Mr. Walter Holmes, the 

 gypsy-moth superintendent for southeastern IMassachu setts, 

 tests were made to determine the effectiveness of the open 

 nozzle in spraying to control the gypsy moth on the bogs. 

 General observations were also made concerning the occasional 

 remarkable decrease in severe gypsy infestations during the 

 development of the worms. 



Hitherto unknown parasites of the cranberry girdler (Crambus 

 hortuellus) were reared. A new control for this pest was de- 

 veloped, — namely, spraying with nicotine sulfate to kill the 

 moths. In connection with this work it was observed that the 

 insecticide was also destructive to leaf-hoppers and spring-tails 

 which usually infest in great numbers the vines of bogs that 

 are not reflowed, and probably reduce their vitality CQnsiderably. 

 These tests and observations added materially to the mass of 

 information from which must be developed the most practical 

 ])rogram for spraying bogs which have water supplies for winter 

 fiowage only. 



Tests were conducted to determine what strength of 

 nicotine sulfate is most feasible for use in a spray to kill the 

 moths of the black-head fire worm {Rhopohota vacciniana). 

 Satisfactory results were obtained. 



The brown span worm {Epclis truncataria var. faxonit) was 

 unusually prevalent, the moths appearing in great numbers on 

 even more bogs than in 1919. Many requests for advice on 

 the control of this pest were answered, with the result that it 

 did little harm except on a few neglected bogs. Important ob- 



