Effect of copper application on copper concentration in white clover and perennial ryegrass on some Northland soils and a yellow-brown pumice soil

Abstract

The effectiveness of copper sulphate (CuSO₄) application in raising the copper (Cu) concentration of white clover (Trifolium repens L.) and perennial ryegrass (Lolium perenne L.) grown together in 5 soils from Northland and a yellow-brown pumice soil was investigated in a pot trial. Dry matter responses of clover were obtained on 3 soils which had less than 1 ppm of EDTA extractable Cu. Ryegrass yield was unaffected by Cu. Cu concentrations in clover and ryegrass increased on all soils except one where clover contained 10 ppm Cu before application. The effect of application on Cu concentration in clover persisted throughout the trial whereas the effect on ryegrass diminished as the trial proceeded so Cu concentration in clover was better than that in ryegrass for diagnostic purposes.

Keywords:

• Copper
• white clover
• perennial ryegrass
• nutrients
• EDTA copper
• fertilisers
• application methods