20 EXPERIMENT STATION. [Jan. 



1. Insects. 

 Observations were {'onlimiod and experiments (•oudiu'ted with the fruit 

 worm and the fire worm (bhack-headed cranberry worm). Numerous 

 growers treated the yellow-headed cranberry worm (or, as it mij^ht be 

 called in Massachusetts, the dry-bog fire worm), under advice given out 

 by the station, apparently with universally satisfactory results. Heavy 

 sanding done by various growers, in some cases, proved successful 

 against the cranberry girdlor. In others it failed to give satisfaction, 

 the failure in every case observed being due to the fact that the sand 

 was not ai)plied evenly over the infested areas. 



The Fruit Worm {Mincola vaccinii (Riley)). — Work was begun 

 on the natural enemies of this insect, with the following objects in 

 view : — 



1. To find out what tliese enemies are. 



2. To determine their relative abundance on flowed and dry bogs. 

 Spraying experiments with arsenicals and adhesivcs were continued. 



It was learned that too much resin fish-oil soap had been used in li)10. 

 While the spraying was not timed so as to give the best results, the 

 experience of 1911 indicates that the following formula will be 

 found more satisfactory than the one given as the result of the 1910 

 experiments: — 



Resin fish-oil soap (poinids), ........ 2 



Bordeaux mixturo: — 



(a) Stone lime (pounds), 5 



(h) Copper sulfate (pounds), 2il> 



Paris green (pound), 1 



Water (gallons), ........... •')0 



Much more of the soap than is here recommended causes bad clog- 

 ging of nozzles and pum]is. 



While the fruit worm injury was reduced about one-third, this gain 

 was largely offset by the loss due to tramping ou the vines and berries 

 while spraying, so that the amount of fruit obtained from the sj>rayed 

 plots was but little greater than that picked from equal areas on the 

 surrounding bog. 



TiiK Fire Worm (Eudetnis racciniana (Pack)). — The season's 

 oksen^ations on this insect seem to indicate that the character of the 

 vine growth has a strong influence on the length of the hatching 

 period of the spring brood. Among thin vines most of the eggs 

 seem to hatch within a few days after hatching begins. With deep, 

 dense vines, this period seems to be so drawn out that numerous eggs 

 are always present throughout the year, the two bj-oods overlapping 

 in this stage. If these obsein'ations are correct, the character of the 



