1012.] PUBLIC DOCUMENT — No. 31. 17 



different fertilizers employed. The crop where nitrate of soda 

 is applied, indeed, showed a small average decrease. Both acid 

 phosphate and high-gi-adc snlfate of potash show a very small 

 average increase, — not in either case enongh to cover the cost 

 of the fertilizer material applied. The results of the year, 

 therefore, do not lend encouragement to the belief that the use 

 of fertilizers on hogs of as good productive capacity as that 

 belonging to the station will be followed by a protital)le increase 

 in the crop. It is important, however, to point out that the 

 a])plication of fertilizers this season was not made until about 

 the middle of July. It seems probable that this is too late for 

 the best results. 



Dr. H. J. Franklin furnishes the following report concerning 

 some of his principal lines of investigation during the past two 

 years : — 



Cranherry Investigations, 1910. 



I. INSECTS.* 

 Of the important cranberry pests heretofore known, those which 

 received attention were the fruit worm, the fire worm and the cran- 

 berry g-irdler. 



The Fruit Worm {Mineola vaccinii (Riley)). 



Experiments in submerging cocoons containing- larva? of this in- 

 sect, for varying- lengths of time during the fall of 1900 and winter 

 and spring of 1910, were carried on without very satisfactory results, 

 due, perhaps, to failure to perfectly imitate natural bog- conditions. 



Spraying- experiments were also carried on, the insecticides used 

 being- mostly combinations of adhesives and arsenicals. The combina- 

 tion found most effective consisted of the following- mixture in 50 gal- 

 lons of water : — 



Pounds. 



Resin fish-oil soap, .......... 4i/> 



Bordeaux mixture : — 



(a) Stone lime, 4 



(h) Copper sulfate, 3 



Paris green, ............ 1 



As the soap had adhesive and spreading qualities, and the Bordeaux 

 mixture gave body to the combination and also acted to some extent 

 as an adhesive, this combination spread over the smooth surface of 



' Dr. IT. T. Fernald has aided Dr. Franklin in the insect work in an advisory way, and for liis 

 helpful sugaiestions Dr. Franklin acknowledges his indebtedness and expresses his appreciation. 



