CONTENTS. 



Part I. 



Organization, 9 



Publications during 1912, 11 



Report of tlie treasurer, 12 



Report of the director, 14 



Report of the agi'iculturist, 21 



The comparison of different materials as a source of nitrogen, . 22 



Muriate v. sulfate of potash, 24 



Comparison of different potash salts for field crops, ... 25 



Comparison of different phosphates, 28 



Average corn fertilizer compared with fertilizer richer in potash, 29 

 Manure alone compared with manure and sulfate of potash, 31 



Comparison of winter and spring application of manure, . 32 



Top-dressing permanent mowings, 33 



Report of the botanist, .35 



Diseases more or less common during the year, 38 



new rust, 41 



Effects of illuminating gas on vegetation, 45 



The effect of illuminating gas on foliage, 50 



Effects of illuminating gas on Carolina poplars, .... 51 

 Stimulating effects of illuminating gas on willow cuttings, . . 53 



Effects of illuminating gas on lenticels, 58 



Illuminating gas as a factor in forcing the development of 



plants, 59 



The influence of various light intensities and soil moisture on the 

 growth of cucumbers, and their susceptibility to burning 



from hydrocyanic acid gas, 61 



Influence of varying percentages of moisture on the develop- 

 ment of cucumbers and their susceptibility to burning from 

 hydrocyanic acid gas. 

 Shade-tree troubles, . 



Staghead and root injur}', 

 Injury to cork cambium. 

 Sun scald. 

 Bleeding, 



Injuries from snow, . 

 Earth fillings, 

 Exposure of roots. 

 Injuries from various treatments, . 

 E.xperiments relating to the control of potato scab. 



Experiments with various chemicals for the prevention of po- 

 tato scab, 87 



