However, Andisols are all acid and where acidity is particularly high, addition of lime may be required to overcome Al toxicity or alternatively acid-tolerant crops must be selected. Where Andisols have been acidified by N inputs, serious consequences for crop production can arise cause as pH decreases, CEC declines towards the p.z.c. As a result, such soils are able to hold few basic cations for plant uptake. Because of their high P-fixing capacities, most Andisols require input of P for successful production. Such input in the form of rock phosphate are effective on very acid Andisols but in any event,soluble P sources should be band placed or otherwise protected from intimate mixing with the soil. Requirements for N vary according to the ease with which organic matter is mineralized in these soils Liming often promotes the release of substantial amounts of N from nonavailable reserves.other nutrients may sometime be deficient in Anisols depending of the chemical composition of the parent material.