Clover sward can replace two thirds of nitrogen at 1.25 acres per cow

Research work by James Humphreys and colleagues in the late 1990s indicated that 200 to 220 units of N per acre are sufficient to support one cow per acre without clover.

Many farmers were using 25% more than what was required, but with the rapid rise in the price of fertiliser, and the Nitrate Directive restrictions, there has been a huge cut back in N fertiliser without loss of production.

With good clover swards, such as in the Teagasc Solo-head farm, 70 units of fertiliser N (including N for silage) are sufficient to support a stocking rate of at least two cows per hectare (1.25 acres per cow).