Animal feed
(1) Animal feed means any crop grown for consumption by animals, such as pasture crops, forage, and grain. (2) Background soil pH means the pH of the soil prior to the addition of substances that alter the hydrogen ion concentration. (3) Cation exchange capacity means the sum of exchangeable cations a soil can absorb expressed in milli-equivalents per 100 grams of soil as determined by sampling the soil to the depth of cultivation or solid waste placement, whichever is greater, and analyzing by the summation method for distinctly acid soils or the sodium acetate method for neutral, calcareous or saline soils (Methods of Soil Analysis, Agronomy Monograph No. 9. C. A. Black, ed., American Society of Agronomy, Madison, Wisconsin. pp 891-901, 1965). (4) Food-chain crops means tobacco, crops grown for human consumption, and animal feed for animals whose products are consumed by humans. (5) Incorporated into the soil means the injection of solid waste beneath the surface of the soil or the mixing of solid waste with the surface soil. (6) Pasture crops means crops such as legumes, grasses, grain stubble and stover which are consumed by animals while grazing. (7) pH means the logarithm of the reciprocal of hydrogen ion concentration. (8) Root crops means plants whose edible parts are grown below the surface of the soil. (9) Soil pH is the value obtained by sampling the soil to the depth of cultivation or solid waste placement, whichever is greater, and analyzing by the electrometric method. (Methods of Soil Analysis, Agronomy Monograph No. 9, C.A. Black, ed., American Society of Agronomy, Madison, Wisconsin, pp. 914-926, 1965.)