Nutrient cycles involving phosphorus and potassium on livestock farms in Northern Ireland

Abstract

SUMMARYA method is described of determining the fertilizer P and K requirements of livestock farms from a knowledge of the stock carried and the crops grown on the farm as a whole. Recycling of P and K through organic manures is put on a rational basis and the fertilizer P and K needed to keep soil P and K at an adequate and constant level is easily measured.A pilot scheme on 100 Northern Ireland farms is testing the method's value for giving advice. It is readily acceptable to advisers and farmers and is enabling substantial savings of fertilizers to be made.