Response of cut grass to potassium and to the mineral Sylvinite
1990
Webb, J. | Whinham, N. | Unwin, R.J.
An experiment was carried out at five sites in England and Wales to investigate the effect of applying potassium (K) at 0, 31 and 62 kg ha-1 in all combinations with sodium (Na) at 0, 20 and 40 kg ha-1. The nutrients in the form of chlorides were applied to perennial ryegrass swards for each of several cuts per year for up to four years. Additional plots received Sylvinite, a naturally occurring mixture of potassium and sodium chloride, at 120 and 240 kg ha-1. At three sites significant (P < 0.05) yield increases due to K and Sylvinite applications were measured when 'available' soil K fell below, 100 mg litre-1 and the K content of herbage from the control plot was 1.2%, of dry matter. At two sites in the absence of applied K there were significant (P < 0.05) yield responses to Na. In all aspects Sylvinite behaved similarly, to mixtures of the two salts at the appropriate levels of application.
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