8a EXPERIMENT STATION. [Jan. 



1. "A Micro Electrometric Method for Determination of CO2." Abstracts of Bac- 

 teriology, V, 1, 1921, p. 5. 



2. "Influence of Vitamin and Nucleic Acid on Azotobacter." Abstracts of Bacteri- 

 ology, VI, 1, 1922, p. 16. 



One other paper has been prepared: "The Relation of Hydrogen Ion Concentration 

 to Azotobacter Chroococcum, Beijerinckii and Vinelandii." This was carried out in 

 co-operation with Professor U. Yamagata of the Imperial University of Tokyo, Japan. 



The work now in progress includes: 



1. A study of the influence of various cover crops on Azotobacter. 



2. Study of the enzymes of Azotobacter. 



3. A study of the influence of various ions on Azotobacter. 



In addition, the study of microbial decomposition of cellulose has been developed as 

 far as time permits, and now includes a physiological study of the organisms isolated, 

 and of the rate of decomposition under various conditions. 



Physiological Studies. 



Botany Project 1. "Optimum conditions of light for plant response." 



Assistant Professor Clark. 



The work under this project is conducted in field, greenhouse and laboratory. In the 

 field, various crops have been grown under three different light intensities: (1) normal 

 light; (2) light reduced in intensity by one layer of cheesecloth; (3) light reduced by 

 two layers of cheesecloth. The object is to determine whether the light factor has any 

 decided influence on the production of seed and on the growth and vigor of resulting 

 seedlings. Seeds and tubers produced this year will be planted next year under normal 

 and modified light conditions. Plants of the biennial type are in storage and will be 

 replanted next year for seed production under the same light conditions in which they 

 were gro\vn this year. Immediate as well as cumulative effect of light intensity is under 

 study in this phase of the work. The field space devoted to the project was considerably 

 enlarged this year. 



In the study of the influence of ultra-violet light on plant growth, little of consequence 

 has developed. A new type of glass which absorbs both heat and the ultra-violet rays 

 has been obtained and is being used in this work. 



Study of the effect of red light in the stimulation of photosynthesis is also in progress. 



Botany Project 15. "A study of plant stimulation by formaldehj'de." 

 This project is temporarily suspended owing to changes in the staff. 



Pomology Project 1. "Study of the interrelation of stock and scion in apples." 



Professor Shaw. 



This project was begun in 1912, and the main orchard set in 1915 and 1916. It is 

 too early as yet to make even a progress report on this work. 



Pomology Project 12. "Apple variety fruit spur study." 



Professor Shaw and Assistant Professor Drain. 



Certain phases of this general study have been taken over by Professors Mack and 

 W. K. French. The former has studied the spur bearing habits of several standard 

 varieties of apples, whUe the latter has investigated the effect of fertilizers on growth 

 and fruit spur formation. Spur samples collected during the summer of 1921 are still 

 awaiting analysis. 



Pomology Project 14. "Winter injury of brambles." 



Professor Shaw, Professor Morse and Assistant Professor Clark. 



This project, co-operative between the Departments of Botany, Chemistry and Po- 

 mology, was organized to investigate the cause of the winter-killing of brambles as ap- 

 parently brought about by differential fertilization with potash salts. See report on 

 Chemistry Project 7, page 7a. 



