1923.] PUBLIC DOCUMENT — No. 31. 17a 



effective in controlling scab, but serious russeting of the fruit by this material definitely 

 eliminates it as a possible apple fungicide, at least for summer application. 



Meteorological records were kept and important observations on the relation of 

 meteorological conditions to sporulation, spore ejection and infection by the scab fungus 

 were made. These data, taken over a series of years, will be invaluable in establishing 

 a definite and permanent spraying or dusting schedule for the State. 



Early in the year the leader of this project, Mr. W. S. Krout, established his residence 

 in the eastern part of the State. This has enabled him to keep m more intimate touch 

 with the field work and has made possible considerable expansion over last year's plan. 



Botany Project 14. "Investigation of control of tobacco wildfire." 



Professor Anderson, 



The disease known as Wildfire has created a grave situation in the tobacco growing 

 industry of the Connecticut Valley. The seriousness of the outbreak the last season, 

 and consequent imperative need of solving the problem of control, made a constant 

 demand on the time of the leader of this project, as well as of others of the department. 

 The importance of thoroughly familiarizing himself with the disease, both in the seed- 

 bed and field, kept the investigator out of the laboratory and on the tobacco farms a 

 considerable portion of the time. In this way much information was gathered which 

 will prove useful in the furtherance of the investigation. 



Botany Project 16. "Relation of soil character to occurrence of onion smut." 



Professor Anderson. 



No progress on this project was made during the past year, on account of lack of time. 



Cranberry Station Project 2. "Cranberry Disease Work." 



Professor Franklin. 



This project was conducted, as heretofore, co-operatively with the Bureau of Plant 

 Industry of the United States Department of Agriculture. Extensive culture work was 

 done to discover the variation in the cranberry fungus flora among different classes of 

 bogs, especially with reference to differences in their flooding. 



Studies were pursued to determme more definitely the relationship of the weather to 

 deterioration of cranberry keepmg quality from the activity of putrefactive fungi. 



Extensive tests were conducted to determine the effect on cranberry keeping of the 

 Wisconsin method of picking known as "water-raking." This was found to be very 

 harmful. 



Extensive storage tests were also made to determine the effect on cranberry keeping 

 of picking during the heat of the day as compared with picking late in the afternoon. 

 The harmful effect of the former was clearly demonstrated. 



Spray Materials — their Nature and Use. 



Botany Project 17. "Potato spraying-dusting." 



Professor Osmun and Professor Anderson. 



This project has for its main object the making of comparative tests of home-made 

 Bordeaux mixture and copper-lime dusts for combating late-blight and other leaf diseases 

 of the potato. 



The conclusions from the first year's work are: 



1. Dusting with hand dusters has not been as efficient as spraying with a power 

 sprayer. 



2. Dusting by hand costs more than power spraying. 



3. The percentage of rotten potatoes was higher in the treated plots than on the 

 check plots. This was probably due to the fact that the vines on the check plots dried 

 earlier and the moisture conditions were then less favorable to development of the disease 

 than where the soU remained covered several weeks longer with a dense mat of vines. 



4. Both spraying and dusting resulted in considerable increase in j'ields over the 

 checks. Spraj'ing gave the greater increase. 



