STUDIES ON THE MAGNESIUM CONTENT OF MIXED HERBAGE AND SOME INDIVIDUAL GRASS AND CLOVER SPECIES

Abstract

The magnesium contents of mixed herbage and four individual grass and clover species were studied under four treatments—control, magnesium sulphate, magnesian limestone and carboniferous limestone.The magnesium values were lowest in the spring and early summer and then increased to maximum values by the autumn. The seasonal variations, however, differed appreciably from year to year.The effect of magnesian limestone on the magnesium content of mixed herbage was relatively small in the year of application, but increased during the following years and reached a maximum in the fourth year after application. The increase in magnesium uptake from the magnesium sulphate treatment was small after the first year, whilst carboniferous limestone slightly depressed the magnesium content. This depression, however, was very small and probably of no practical significance.The magnesium content of red clover was about 50% higher than that of Italian ryegrass, cocksfoot and white clover. In the second year after application magnesian limestone had a much greater effect on the magnesium content of the clovers than on that of the grasses.