Does a soil acidity test as used in soil testing laboratories determine our calcium need in Ohio soil?

Tiedjens, Victor A.

ABSTRACT:  Soil samples from many sections of the United States and Canada show a paucity of available calcium even though the pH reading seems satisfactory. Studies made on these soils show that the pH test, accurate for most purposes, does not indicate the available calcium in the presence of other fertilizer ions. A high pH does not necessarily indicate adequate calcium in the soil.

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