FIELD CROPS. 799 



The results of fertilizer tests varied according to tlie soil on wliicli 

 the crop was grown. In 1889, on a very heavy dry clay soil, 500 lbs. of 

 fresh cotton seed gave the largest yield. In 1890 and in 1891 the most 

 IDrofitable fertilizer was a compost of stable manure, cotton seed, acid 

 phosi)hate, and kainit. In 1892, on a heavy red clay soil from wiiich 

 the surface soil had been badly washed and which liad given a light 

 crop of lespedezathe preceding year, 210 lbs. of cotton-luill ashes gave 

 the largest yield, an increase of 123 per cent over the yield of the unfcu^til- 

 ized plats. In 1893, on a heavy soil which had grown a crop oi' cow- 

 peas in the preceding year, 500 lbs. of kainit to the acre more than 

 doubled the yield of the unfertilized plat. Results of fertilizer tests at 

 Holly Springs are also stated. 



"From the Avork which has been clone both at Holly Sin'lngs and at the home 

 Btation, there seems to be no great diffei'ence between the fertilizers required lor 

 corn and those which are most needed for cotton. The first essential for both is 

 evidently an abundant supply of humus, which cau be provided most economically 

 by the plowing under of green leguminous crops, but which may be supplied in 

 stable manure, cotton seed, or [cotton-seed] meal With a soil rich in humus and in 

 lime, potash should be used liberally, while but little phosphoric ncid and no nitro- 

 gen need be given. Where lime is deficient both potash and phosphoric acid should 

 be used, and if deficient in humus, nitrogen should also be applied in the form of 

 [cotton-seed] meal for sandy soils and [cotton] seed for heavy clay uplands." 



Experiments with cotton, S. M. Tracy {Mississippi Sta. Bpt. 1893^ 

 pp. 6-17). 



Synopsis. — The results of 5 years' work in fertilizer testa in 3 localities and of 

 variety tests are summarized. Fertilizer tests indicate that the soil of the sta- 

 tion farm is especially benefited by manures or fertilizers rich in organic matter 

 and potash. At the Holly Springs Substation results were not decisive. At 

 the Lake Substation phosphoric acid proved superior to potash. Tlie value 

 of the crop for the 6 varieties affording the greatest value per acre (in lint and 

 seed) in each of the 5 years of the experiment are given and the results for 1?<93 

 are tabulated in full. 



Fertilizer experiments (pp. 6-13). — At the station in 1889 200 lbs. of 

 kainit i>er acre proved the most effective and economical fertilizer. In 

 1S90, on a similar soil, the Furman compost (containing 750 lbs. of stable 

 manure, 750 lbs. of cotton seed, 333 lbs. of acid phosphate, and 1G7 

 lbs. of kainit per ton) proved most economical, though sulphate of pot- 

 ash afforded nearly the same yield. 



In LS91 , on an exhausted, dry, yellow clay hill the best results followed 

 the use of 1,000 lbs. of cotton seed per acre; on a heavy red clay soil 

 15 tons per acre of stable manure produced the largest yield, while 

 kainit gave the cheapest increase in crop; on an exhausted yellow loam 

 the substitution of kainit for the acid phosphate in the Furman com- 

 post largely increased the yield and cheapened the cost of production 

 both in 1891 and 1892. Again in 1893 a compost rich in potash gave a 

 larger yield than one relatively poor in this ingredient and rich in phos- 

 phoric acid; 500 lbs. of kainit alone increased the yield by 222 lbs. of 

 seed cotton per acre, while 250 lbs. of acid phosphate alone produced 

 no notable effect. 



