Letter | Published:

Relationship between Base Saturation and Crop Response to Phosphate in Acid Soils

Naturevolume 168pages388389 (1951) | Download Citation



IN an attempt to relate phosphate responses in the field with soil analyses, the most significant correlations I have yet obtained have been between response and the percentage saturation of the base exchange capacity. It should be noted that all the soils, with one exception, lay within the range pH 4.7–6.3. In three groups of experiments (fifty-six observations) on wheat, grass and millet, the regressions of crop response (percentage increase in yield due to superphosphate over control) on the percentage saturation of the base exchange capacity were highly significant (P < 0.01) in spite of the fairly wide variation in soil types. The relationship was an inverse one, and the equations indicated that phosphate responses are not to be expected when base saturation exceeds about 80 per cent. A similar relationship was found between response and exchangeable calcium expressed as a percentage of exchangeable calcium plus exchangeable hydrogen, that is, in units similar to the percentage saturation of the base-exchange capacity.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    Burd, J. S., Soil Sci., 65, 227 (1948).

  2. 2

    Allison, L. E., Soil Sci., 55, 333 (1943).

  3. 3

    Barbier, G., and Chabannes, J., Ann. Agron., 19, 343 (1949)

  4. 4

    Ravikovitch, S., Soil Sci., 38, 219 (1934).

Download references

Author information


  1. East African Agriculture and Forestry Research Organization, P.O. Box 21, Kikuyu, Kenya Colony

    • H. F. BIRCH


  1. Search for H. F. BIRCH in:

About this article

Publication history

Issue Date



Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.