Effects of cow urine on growth of pasture and uptake of nutrients

A field trial was conducted on permanent pasture on Marton loam with cow urine and a nearly equivalent rate of KC1. Its objects were : To determine the apparent recovery of applied nitrogen and potassium. To evaluate the effect of these treatments on the magnesium and calcium in pasture and soil. The apparent recovery of applied nitrogen in the herbage was only 10 per cent of that applied in urine. The apparent recovery of potassium in the herbage was 20–23 per cent of that applied in urine or KC1. No difference was observed in the action of potassium whether applied as urine or as KC1. The effect of urine nitrogen on yields and on N concentration in the pasture lasted only about two months. The effect of applied potassium on yields and K concentration in the pasture was significant for two years. Urine and KC1 depressed the concentration but not the uptake of Mg and P in the herbage and slightly lowered the level of exchangeable magnesium in the soil. Considerable losses of N and K and some losses of Mg and Ca are likely to occur under urine spots.