1918] SOILS — FERTILIZERS. 219 



years will produce satisfactory crops for some time without further fertiliza- 

 tion." 



The lime and fertilizer needs of Indiana soils, S. D. Conner {Indiana Sta. 

 Circ. 66 {1911), pp. 19, figs. 8). — This circular, based on the results of various 

 studies of Indiana soils, identifies and classifies in a general way the principal 

 types of soil of the State, and gives methods whereby the soils may be tested 

 for their lime and fertilizer requirements by farmers, teachers, or agricultural 

 agents. 



It is shown that many of the soils have declined in productiveness as a result 

 of exhaustive cropping. The soils have been depleted especially in organic 

 matter and nitrogen but also in available phosphoric acid. Over three-fourths 

 of them are acid, and on practically all of these available phosphoric acid is 

 needed, either with or without lime. " Potash fertilization has proved profitable 

 on some soils. Neutral or slightly acid muck and black sand soils need potash, 

 particularly for corn." 



A soil-acidity map and other data are given, showing the relative proportion 

 of very acid, medium acid, slightly acid, and neutral soils in each county of tlie 

 State, as determined in over 4,000 samples of soil by the potassium nitrate 

 method. These data show that no section is without an abundance of acid soils, 

 the relative proportion for the entire State being 19.6 per cent very acid, 24.2 

 per cent medium acid, 38.2 per cent slightly acid, and 18 per cent neutral. 



Practical methods of ovei'coming the soil deficiencies, such as the growing of 

 more leguminous crops, liming, use of acid phosphate and potash, and more 

 careful conservation and use of manure and crop residues, are discussed. 



Redeeming' an impoverished soil, C. E. Thorne {Mo. Bui. Ohio Sta., 2 

 {1911), No. 10. pp. SSD-SJ/S). — Increased yields of corn, soy beans, wheat, and 

 hay, grown in rotation on the rather depleted flat, silty clay land of Clermont 

 County (Ohio), were secured from applications of different combinations of com- 

 mercial fertilizers, lime, and manure. The estimated value of the increase is 

 noted in each case for the period of 1912 to 1917. It is concluded that under 

 present market conditions of fertilizers and ci'ops, an increased net income of $3 

 per acre or more, annually, could be attained by the use of chemical fertilizers 

 alone, but that under a system whereby manure could be applied at the actual 

 cost of moving it from the stable to the field, necessitating the purchase of only 

 acid phosphate, an increased net income of $5 per acre or more would be possible. 



Fertilizer requirement of DeKalb soil {Pennsylvania Sta. Bui. I4I {1911), 

 pp. 20-22, fig. 1). — Preliminary pot and small plat tests, begun in 1915, with 

 various legumes and grasses on both abandoned farm land and virgin cut-over 

 land to determine the fertilizer requirements of DeKalb soil are reported. In 

 the small plat test limestone, applied at the rate of 5,000 lbs. per acre, was com- 

 pared with an imliraed area. In the pot tests various fertilizers were tested in 

 different combinations. 



Limestone alone produced the following results, in pounds per acre, on the 

 two soils on small plats. Green sweet clover, limed, 4,083 and 7,984, respectively, 

 unlimed, nothing; green red clover, limed, 3,886 and 3,896, unlimed, 1,523 and 

 2,213. " Orchard grass gave better results than either brome or blue grass on 

 the plats treated with limestone. In the pot tests the greatest growth of blue 

 grass on the farm soil occurred in the pots treated with lime, nitrate of soda, 

 and acid phosphate, while the lime, nitrate of soda, acid phosphate, and potash 

 treatment produced the greatest yield on the virgin soil. Limestone and phos- 

 phoric acid gave an increase of 125 per cent of sweet clover over limestone alone 

 on the farm soil as compared to 580 per cent on the virgin soil," 



