BULLETIN No. 212. 



DEPARTMENT OF AGRICULTURE. 



A THIRTY-YEAR FERTILIZER TEST. 



BY SIDNEY B. HASKELL. 



History of Plots. 



In Febraary of 1889 Dr. W. 0. Atwater, then director of the Office of 

 Experiment Stations of the United States Department of Agriculture, 

 issued a call for a conference to consider and adopt if practicable a uniform 

 method of conducting what were then called soil tests. As a result of this 

 call a conference was held in Washington, this Station being represented 

 by Professor Wm. P. Brooks. A method of testing the soil by means of 

 comparative field plots was decided upon, and in Massachusetts a number 

 of such tests were instituted. Two of these were on the Station grounds, 

 — the South Soil Test started in 1889 and the North Soil Test in 1890. 

 Nine similar tests were laid out in other parts of the State. The object 

 was "to find out the particular fertihzer requirements of the soils of differ- 

 ent localities;" and in the letter sent out arranging for the co-operative 

 tests, the statement was made that "the best soil for the purpose is one 

 which represents best the average conditions in your county, which is 

 level or of uniform moderate slope, of uniform and low fertility, and now 

 in grass." 



Up to and including 1917 these soil tests were under the supervision of 

 Dr. WiUiam P. Brooks, formerly agriculturist and later director and 

 agriculturist of the Experiment Station. Progress reports under the au- 

 thorship of Dr. Brooks were made in Bulletins Nos. 9, 14, 18 and 58 of the 

 Hatch Experiment Station, and like\^^se in the annual reports of that 

 Station and its successor, the Massachusetts Agricultural Experiment 

 Station. Records from these tests, with analysis and discussion, were 

 also pubhshed in "Das Nahrstoffbediirfnis Verschiedener in Fruchtfolge 

 auf demselben Felde Angebauter Pflanzen nach Versuchen in Massachu- 

 setts, Nordamerika," presented by Dr. Brooks at the University of Halle, 

 Germany, as a doctorate dissertation. 



The greatest service of these field tests to date has probably been the 

 establishment of the fact that individual crops vary widely in their plant 

 food requirements, and that fertility practice may be affected more by 



