147 



Tlic soils used in these oxp(M-iiiuMits wore typical ones, so that the re- 

 sults Avill interest farmers occu[)vin<j; similar lands. When purchased 

 by the Station "all thive farms [at Sjiartanburg, Darlington, and 

 Columbia I wei-e in wretched condition, worn out l)y years of improvi- 

 dent tillage."" At Darlington the soil is an ajjparently sterile sand, on 

 which ai"e a few tufts of worthless grasses; the subsoil contains some 

 clay. At Spai-taiil)urg theiv is some clay in the surface soil: the sub- 

 soil is clay. 



Fertilizer!^ oti odtn. — (1) Special nitrogen experiments. — {a) At 

 Darlington : Six acres of the poorest land were divided into half-acre 

 plats. Five kinds of fertilizing mixtures were used in duplicate tests 

 on ten plats. The other two plats were unmanured. The full 

 amounts of nitrogen, phosphoric acid, and potash (52 pounds, 19 

 pounds, and 38 pounds, respectively) estimated to be contained in the 

 grain and straw^ of a crop of 45 bushels of oats per acre, were supplied 

 in mixtures in the tirst three tests, while in the other two, one-half the 

 c{uantity of nitrogen was furnished. Acid phosphate was used for 

 phosphoric acid; nniriate of potash and kainit for potash; cotton seed 

 or cotton-seed meal for nitrogen, with some phosphoric acid and pot- 

 ash; and nitrate of soda for nitrogen alone. These materials thus 

 furnished the phosphoric acid and potash of a crop of 45 bushels, and 

 either all or half the nitrogen of the same crop, the nitrogen being 

 supplied as nitric acid, organic nitrogen, or the two forms mixed. 

 Details of the experiment are given in a table. The yield on the fer- 

 tilized plats varied from 15.5 bushels to 26.5 bushels per acre, while on 

 the unfertilized plats it averaged only 7.8 bushels. It appeared that 

 52 pounds of nitrogen per acre was an excessive amount for this soil, 

 as one half the amount gave equally good results. Inorganic nitrogen 

 gave better results than organic, {h) At Spartanburg: Five plats of 

 1 acre each were used and the tests were not duplicated. Four diifer- 

 ent mixtures of fertilizers were applied on four diiferent plats and 

 one i)lat \\as unmainu'ed. The quantities of potash and phosphoric 

 ax;id were not in all cases the same as in the Darlington experiments. 

 The yield on the unfertilized plat was 8.4 bushels; on the fertilized 

 plats it varied from 18.7 to 38.8 bushels. Tlie results were decidedly 

 favorable to inoi-ganic nitrogen. 



A comparison ot" four of the tests conducted on both farms indicates 

 that the inorganic nitrogen gave nearly 100 i>er cent more increase of 

 3'iold than the organic, and nearly 50 per cent juore than both forms 

 used together.' 



(2) Special phosphoric acid experim.ents. — The object of these ex- 

 periments Avas to test the relative value of floats and Thomas scoria 

 (basic) slag. {a) At Darlington: These were on two quarter-acre 

 plats immediately adjoining those used in the above-mentioned experi- 

 ments. The"tests were not duplicated. One hundred pounds per acre 

 of nitrate of soda were used with the phosphate. The yield was at 

 the rate of 11.8 bushels per acre with the slug, and !>.T5 bushels with 



