2G() STATE BOARD OF AGRICULTURE. 



CO-OrEKATJVH SOIL TEST KXPEKIMI^LXTS. 



KV .1. I). TOWAi;. 



Bulletin 18]. — Agricultural Department. 



I'^oUowiiifr (ho plan suujiosted l)y Prof. Atwator. on pafrcs 24 to 28 of Circular No. 

 7. Oliicc of Experiment (Stations, on "Co-operative E.xperinients with Fertilizers," the 

 department befjan a series of soil test experiments in the sprinjj of IS!)!). The ofVcr 

 to ccmdnet a limited number of these experiments was made by the department and 

 ]uiblished in the M. A. C. Record, from which it was copied by several other newspapers 

 in the State. A preat many more farmers than could be acconnnodated accepted the 

 offer, thereby frivin^i: ns a large area of the 8tate for selection of localities. The 

 l)laces selected for conductins; the experiments were decided upon as to their geographi- 

 cal distribution in the State, proximity to the railroad, and general location for 

 making a convenient ronte in visiting the various places. The de])artment was gener- 

 ally fortunate in the selection of men and places for this work. In every case where 

 the experiment was under the direct charge of the man owning the farm perfect satis- 

 faction and a carefully conducted experiment was the result. A few unforeseen 

 calamities, and in some ca.ses unfortunate selection of groiuul for the experiment, ren- 

 dered valueless some of the results obtained. 



The crops sown, unless for some particular reason it became necessary to make a 

 change, were corn, potatoes, lield beans and sugar beets. Tlie i)l()ts were usually laid 

 out in a way that the whole would occupy nearly a square area, thus making the 

 twelve or thirteen ]ilots about ten or twelve times as long as they were wide. This 

 afforded convenient areas of each crop by sowing the seed in rows crosswise of ferti- 

 lized plots. In general, the arrangement of plots and the amount of fertilizer applied 

 were as follows: 



Arrangement of ]ilot in soil test experiment and amount of fcililizers ajjplied per 

 plot of 1-10 acre each: 



Plot 1, no fertilizer. 



Plot 2. 12 pounds nitrate of soda. 



Plot 3, 24 pounds dissolved phosphate rock. 



Plot 4, 12 pounds muriate of potash. 



Plot .'5, no fertilizer. 



Plot (), 12 pounds of nitrate of soda. 24 pounds dissolved ])hos])hate rock. 



Plot 7, 12 poimds nitrate of soda, 12 poimds muriate of potash. 



Plot 8, 24 pounds dissolved jiliosphate rock, 12 j)oimds muriate of potash. 



Plot '.), no fertilizer. 



Plot 10, 12 ])ounds nitrate of soda, 24 pounds dissolved jdiosphate rock. 12 pounds 

 muriate of potash. 



Plot 11, 48 pounds commercial fertilizer. 



Plot 12, 2 lorfds stable manure. 



Plot 13, no fertilizer. 



A space of three feet was left imfertilized between the ])lots, though this ground 

 was planted the same as the fertilized areas. The nitrate of soda used in this experi- 

 ment contained 18.7 per cent ammonia. The dissolved phosphate rock, 15.85 per cent 

 available phosphoric acid, and 1.82 per cent insoluble, making total phosphoric acid 

 17.G7 per cent. The muriate of potash contained 49.85 per cent potassium oxide. The 

 commercial fertilizer used was a wheat and corn fertilizer offered by a leading manu- 

 facturer, but, unfortunately, we have not the exact analysis of this material. It 

 will be seen by the above that plots 2, 3 and 4 were devoted to the single elements — 

 nitrogen, phosphoric acid and potash; plots 6, 7 and 8, to combinations of two of these 

 elements, while plot 10 combined all three of the essential elements of plant food. 



