DIVISION OF AGRICULTURE. 



WILLIAM P. BROOKS. 



SOIL TESTS WITH FERTILIZERS. 



Duriug the season of 1891, Soil Tests with Fertilizers have been 

 carried out under my supervision in the counties of Essex, Middlesex, 

 Worcester, Hau][)shire and Franklin under the care of selected 

 farraeis; and, except in one instance, upon land which had already 

 been used one or two years in a similar test. In all such cases the 

 fertilizers were applied upon the same plots as in preceding years. 

 The experiment in Worcester county was with oats, the rest with 

 potatoes. Besides these we have had two acres in a similar experi- 

 ment upon our own grounds, one in oats and one in potatoes, and a 

 number of volunteer workers in different parts of the state who 

 planted corn. In the following pages will be found an account of 

 the experiments in the counties above named as well as of those on 

 our own grounds and of two volunteer workers whose results seem to 

 have been accurately determined. 



The general plan of experiment was similar to that followed during 

 the two preceding years and it is described in full in Bulletin No. 9 

 of this station. One acre was used in each experiment and this with 

 one exception, (where there were fourteen) was laid out in fifteen 

 plots of one-twentieth of an acre each, the unfertilized strips around 

 and between the plots occupying the balance of the acre. The 

 fertilizers used were nitrate of soda, dissolved bone-black, muriate 

 of potash, land plaster, lime, and barn-yard manure. The first 

 three mentioned fertilizers were selected as sources respectively 

 of nitrogen, phosphoric acid and potash, which are recognized to be 

 essential elements of all fertilizers and manures, — often indeed they 

 appear to be the only essential elements. The reason for selecting 

 these materials is that they allow us to furnish essentials of plant 

 food singly or in any desired combination. Other materials might 

 serve the farmer's purpose equally well ; but for our purpose we must 

 have forms of fertilizers which enable, us to trace results to definite 



