Soil mineral nitrogen (SMN) tests, used on half our regional representatives’ farms, suggest there is less Nitrogen than usual left in the land after the mild winter and sodden February.
Nevertheless, the lightest land aside, noone has rushed to top-dress first wheats, with most planning to delay until early April.
Where there was a need, in oilseed rape, barley and second wheats, some intended treatments have been thwarted by bad weather.
Andrew Gloag is not alone in having crops much more forward than normal on his heavy land.After 200mm (8in) of rain since 1 December SMN levels average only 25kg/ha.
“But first wheats have more than enough tillers,” he comments.
James Wray suspects test results on land still at field capacity will show low N reserves, despite last autumn’s use of chicken manure.
“But the wheat’s very lush so I plan to use urea rather than Nitrochalk as soon as we can get on.”
On land Troy Stuart farms agronomist Howard Moore says SMN reserves are 40kg/ha lower than last year, but crops have taken up 10kg/ha more than usual.
Feeding that into the UAP Nitrogen Calculator suggests an extra 50kg/ha of bagged N will be required for winter wheat.
However yield may have been hit by 860mm (34in) of rain from October to early March, he believes.
“Nitrogen rates on wheat and grain maize are likely to be much higher this year, with rape being near average because of good N levels in the crop buffering low soil levels.”
“This year from end of February tests we have average soil levels of 37kg/N in oilseed rape and 45kg/N in winter wheat.”
So, overall dressings will be as usual with possibly a little less on winter wheat.
“Some winter wheat is starting to look hungry. However with such lush crops I cannot risk feeding them until I have the first PGR applied.”
High-potential oilseed rape however will get plenty of N including a petal fall 20kg/ha.
“Trials show this late application is a real yield booster.”
John Barrett tried soil testing for N last year for the first time but has not repeated it.
“But we use a lot of muck, and there were several inconsistencies in the results, so I’m not convinced.”
Given the manure none of his wheats, except one second crop, had received anything by last weekend.
“None of them look as though they are crying out for it.” However dressings, including sulphur, to fast-growing oilseed rape had been completed.
Nigel Horne does not yet test soils for N but would not be surprised if spring levels prove lower than normal.
“So I don’t expect to be applying significantly less than usual.”
He has no plans to dress any first wheats or complete oilseed rape treatment until April.
“The rape, which looks much more forward than normal, has probably trapped some soil nitrogen which would otherwise have been leached. The difficulty will be in attempting to quantify this.”
Farming outside an NVZ, John Hutcheson sees no need for soil testing yet. “There’s not so much pressure to justify N levels.”
Inputs will be much like last year, though wheat will have only 50kg by the end of March.
“There’s no immediate need for any more.”
But barley and oilseed rape applications have been delayed by bad weather.
“We’ve changed to liquid N this season because we get too many windy days and it’s difficult to get an accurate spread pattern at 24m.
“But I did buy some granular urea for about 25% of our requirement due to its lower cost and being able to get round faster.
“The plan was to get this on first when temperatures were lower, but wet and windy conditions meant it wasn’t possible, so the liquid has gone on first.”
Richard Solari likes to apply at least some early N on his light land.
“That’s in case we get a dry spell. If it doesn’t rain for three weeks the fertiliser can just sit there doing nothing.”
He doesn’t soil-test. “But after all that rain in February we have to assume most of the nitrogen’s gone.”
However, all advice has been to hold back with nitrogen this year, notes manager, Rob Waterston.
That said winter barley has begun to green up after 60kg/ha of N and 70kg/ha of SO3 in the first week of March, and wheat had the same dressing a week later.
“We tried to apply some nitrogen the week before to some December-sown wheat, but managed to get the sprayer stuck.”
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