HIGHER RESIDUAL soil Nitrogen levels following a dry winter could allow some growers to cut back on fertiliser this spring, said ADAS.
Soil N levels are around 30kg/ha higher than average years and could therefore allow growers to cut N inputs by a similar amount, said ADAS soil scientist, Peter Dampney.
“A consistent pattern is emerging. By mid-February, between 10 and 30kg/ha less N had been leached than in a normal year.”
But not all growers will be able to cut rates, he warned. Firstly, farmers and advisors using the RB209 advisory book need to carry out an accurate assessment of soil nitrogen supply (SNS).
Where the SNS index is 0 or 1, the effects of the dry winter are minimal, he said.
“Also, on easily leached sandy or shallow soils, the available N is lost quickly and most will be gone.”
For further information on the ADAS monitoring and a guide to recommended N rate adjustments, see this week‘s FARMERS WEEKLY (March 25-31).