Give grass boost of N if planning an early turnout
Give grass boost of N if planning an early turnout
DAIRY producers planning to turn-out early should consider applying nitrogen as soon as ground conditions are suitable.
New Zealand dairying consultant Paul Bird, working in the UK, suggests producers apply urea to those fields due to be grazed in early to mid-March.
"Theres no point spreading on fields due to be grazed in the next two to three weeks – but get N onto fields which will be grazed last in the first rotation." He suggests applying about 50kg/ha (40 units/acre) of urea.
Producers who plan to turn-out later, in March, should spread N over the bulk of the grazing area. "This grass wont be so long and will need a boost, so spread now."
Irish grassland researcher Willie Murphy, Johnstown Castle, Wexford, also suggests farmers in the west of England and Wales could apply early N.
"Where the conditions are right for grazing in February/March early nitrogen will maximise growth." As a rule of thumb he suggests applying N six weeks in advance of the grazing date.
Mr Murphy cites Irish research to show that early N is best applied as urea. "It is at least as effective as ammonium nitrate – but because it moves more slowly in the soil and converts fairly rapidly to ammonia, it is much less prone to leaching than AN."
Mike Dewhurst of Fieldfare consultants agrees that producers planning to turn-out early could start spreading N now.
But he cautions that early N use is only really applicable to producers on lighter soils who can use the grass without causing poaching.
Application is better delayed on wetter/higher fields or on farms where turnout is planned for late March/early April. "Wait another fortnight or so until the T-sum 200 mark – towards the middle to end of February – before applying N".
ADAS fertiliser specialist Peter Dampney is also cautious about use of early N. He warns that theres plenty of winter to go yet, and is against spreading fertiliser now.
"Even though there may be a lot of grass, it wont grow actively for a while yet – day length and radiation from the sun arent sufficient."
He says that the combination of more residual nitrogen in the soil and a mild winter – which encourages N release – should mean there is enough N in the soil to keep current growth going. "The heavy rain probably wont have caused much leaching – often it will just wash off the surface.
"I would recommend producers think about applying N in mid-February if it is still mild and the forecast is for dry weather. There is evidence to suggest that urea may be the best option, but that depends on the quality as it can be more difficult to spread evenly." *
NITROGEN USE
NITROGEN USE
• For early grass spread now.
• Urea best for early N use.
• 6-8 weeks for response.