SCORES BULLS EYE FOR FARM GROUP
ONE-HIT NITROGEN REGIME
SCORES BULLS EYE FOR FARM GROUP
Established nitrogen
fertiliser practice dictates
splitting applications to
achieve best wheat yield
and quality. But results
from one farmer
competition suggests a
simpler approach can pay.
Robert Harris reports
APPLYING nitrogen in a single dressing in a dry spring has no effect on wheat yield or quality and saves money.
A sweeping statement, perhaps. But the one-hit approach has worked for one group of farmers on a range of soil types over several seasons, with both feed and bread-making varieties.
Huntingdon Snifters have become the team to beat in the Lloyds Bank Farmer Challenge. The competition is held annually on the Cereals Event host farm and sees several teams vying to squeeze the most profit from a crop of wheat.
The Snifters first entered the competition in 1994. The groups Brigadier produced a healthy 9.2t/ha (3.7t/acre) on the thin, chalky soils at Oliver Walstons Thriplow Farm, near Cambridge.
That was 1t/ha (0.4t/acre) ahead of the nearest rival, and well above the budgeted yield of 7.4t/ha (3t/acre).
Nitrogen was applied in two lots that year. The first, 44kg/ha (35 units/acre), went on at the end of February, topping up a similar amount of available soil N. The rest, 170kg/ha (135 units/acre) of ammonium nitrate, was applied to rapidly drying soils in one pass in the third week of April.
"Normally we would go three times on our own farm," says group member David Brown, who grows 237ha (585 acres) of wheat and oilseed rape on skirt land and boulder clay at Fenton Hill Farm, Warboys, Cambs. "But in a competition you have to cut corners a bit."
Boulder clay
Colleague Philip Lea grows 162ha (400 acres) of wheat and oilseed rape on boulder clay at Sapley Park Farm, Sapley, Huntingdon. "We wanted to save a pass, but we wanted to be sure the crop had enough nitrogen," he says. "Had we applied some in May, when soils were dry, the crop might not have taken it all up."
Ammonium nitrate was favoured over urea, Mr Browns usual choice on farm. "We were applying a large amount of N fairly late. We didnt want to lose any in the heat, and AN works quicker too."
Other inputs were unaffected, a trend continued each year. Final profit was £26/t before aid.
The following year LBFC moved to light, sandy loam soils at Shuttleworth College. The competition plots followed potatoes, and residual N levels were high.
The Snifters pegged nitrogen rates to 170kg/ha (136 units/acre) and applied it all to the Brigadier on April 11.
The crop was thick and forward. "Given the light soils, we didnt want to encourage too many tillers and produce thin grain by applying N too early," says Mr Lea.
Application costs, often ignored on farm, were priced at £6.25/ha (£2.53/acre). Most other groups stuck to two or three applications, spending up to £12.50/ha (£5/acre) more.
Although Huntingdon did not win in 1995, mainly due to selling grain slightly earlier than the winning team, they again achieved the highest yield, 10.2t/ha (4.13t/acre). Profits topped £45/t.
Winning ways
Last year saw a return to winning ways on the heavier boulder clays at Bill Turneys Weybridge Farm, Alconbury, near Huntingdon.
Wheat plots followed oilseed rape, and residual N levels reached 141-212kg/ha (112-170 units/acre).
Dry seed-beds caused thin plant stands. Despite that, the group held off until April 4 when the Charger received 206kg/ha (165 units/acre) of ammonium nitrate.
"The large soil nitrogen reserves certainly influenced our decision," says Mr Lea. "We didnt really set out on a one-pass approach, but the crop never looked hungry after rape." Application costs had also risen to £6.90/ha (£2.79/acre).
Yield, at 8.8t/ha ((3.6t/acre), was 12% below expectations, mainly due to the difficult season. The second-placed group grew Rialto and split its N three ways. That added almost £14/ha (£5.66/acre) to costs, but was not repaid in the dry season.
Yield was 0.2t/ha less, and although the protein content was slightly higher than the Chargers 11.6%, both crops sold for £104/t.
The Charger made a 333 Hagberg and a specific weight of 77.5kg/hl, and produced a profit of £22.37/t before aid, over half of that due to the reduced number of passes with the fertiliser spinner.
Neither farmer will adopt the competition approach on their own farms, for logistical, rather than agronomic reasons.
"But we have learned we can shave a few corners and still get the end results," says Mr Brown. "While some cost savings can be made, the most important message is to get the right amount of nitrogen on.
"I am not a great fan of spoon-feeding. On the back of these results I would certainly be prepared to go twice, rather than three times, a season, especially in a dry spring. But if the soil was wet you might want to be a bit more careful." *
ONE-HIT N POLICY
• No yield penalty.
• Quality maintained.
• Application cost savings.
• Caution needed in wet seasons?
• Practicality concerns on farm.
Applying nitrogen in one pass proved a winning recipe for Huntingdon Snifters (from left):David Brown, Philip Lea, John Burgess and Ray Woolway. Wheat yield and quality matched that of spoon-fed crops.