Part 1, Section 2: Soil Fertility Management
Soil Fertility Management
SOIL ACIDITY AND LIMING
Although the best practice is to apply the recommended amount of a liming material, a partial application should be considered rather than no application at all. If only partial applications are made, it is best not to attempt to grow acid-sensitive crops such as alfalfa.
When less than the full limestone requirement is applied, make the application after primary tillage and incorporate it by secondary tillage, thus mixing the limestone 4 inches into the surface. This ensures a better environment for germinating seeds and young seedlings, as well as more effective herbicide action in the surface soil layer.
When high rates of limestone are recommended (4 tons or more per acre) the applications should be split. See Table 1.2-1 for guidance on splitting high limestone recommendations. Separate the applications by 6 months time or at least by tillage operations. In a tillage based management system, plowing part of the limestone down and then applying the balance and incorporating with secondary tillage is an excellent way to correct the pH in the whole plow layer.
As soil acidity increases (soil pH becomes lower), the need to apply a liming material to any crop and the expected returns of applying it become greater. If soil acidity is limiting crop production, other production inputs such as fertilizer, seed, pesticides, machinery costs, and labor will not realize the kind of return that would be possible on a well-limed soil.