The relation between herbage copper, EDTA-extractable soil copper and species composition in pastures growing on a range of soil types

Abstract

A survey of the copper status of herbage and its supporting soil over various soil parent materials (all with acid soils) on part of the coast of New South Wales showed levels of herbage copper ranging from < 1 to 14 ppm, EDTA-extractable soil copper from 0.2 to 32 ppm and a correlation between these two variables of r = 0.51 (P < 0,001). Very low levels of herbage copper were associated with high proportions of inferior grasses and both were associated with low 'available' soil copper. High levels of herbage copper were associated with high proportions of clover though not necessarily with the highest levels of 'available' soil copper. The content of molybdenum in herbage varied widely giving many very low copper/molybdenum ratios.