1917.] PUBLIC DOCUMENT — No. 31. 45 a 



DEPARTMENT OF AGRICULTURE. 



WM. P. BROOKS AND E. F. GASKILL. 



The work of the agricuUural department during the past 

 year has progressed along already well-defined lines. A large 

 share of the work consists in the care and management of a 

 large number of field plots which have for their object the 

 study of various phases of the question of soil fertility. Many 

 of the field experiments have continued over a long period of 

 years, and a large amount of data have been accumulated which 

 have been of great assistance in determining the specific plant- 

 food requirements for various crops. 



The work of the department during the past year has in- 

 volved the use of 221 field plots, 13 orchard plots, 23 pasture 

 plots, 143 closed plots and 388 pots in our vegetation experi- 

 ments. The closed plots and the vegetation pots are used 

 largely to check results obtained in the field. The department 

 has also been called upon to supervise the field work on the 

 Tuxbury land, which comprises about 20 acres, and on most of 

 which are set young fruit trees to be used in experimental work. 

 The care of the newly leased Tillson farm of about 75 acres has 

 also been placed temporarily under the supervision of this 

 department. 



In presenting the work of the department from year to year 

 it has not been customary to attempt a complete report of all 

 the activities, but to mention and discuss only a few of the 

 more striking results of the year. This policy will be followed 

 this year. 



Field A, or the Nitrogen Experiment. 

 The object and plan of this experiment have been described 

 in several of the earlier reports. The crop this year was 

 potatoes, which, owing to poor seed, was a failure and had to 



