Crop Watch: Weather upsets spray plans
The change to more unsettled weather this week was hampering fertiliser and spraying plans, according to our Crop Watch agronomists.
Prime Agriculture’s Norfolk-based agronomist Marion Self was eagerly awaiting a drier spell to complete her spraying programme for blackgrass and other broad-leaved weeds.
“When conditions improve, we’ll apply outstanding sprays such as Atlantis (mesosulfuron + iodosulfuron) on wheat and in oilseed rape clopyralid-based sprays, such as Galera for sow thistle, mayweed control and cleaver suppression,” she said.
Backward oilseed rape crops, barley and later-drilled wheats also needed their first dose of nitrogen and sulphur, she added.
AICC agronomist Tod Hunnisett in Hampshire said early-sown wheats and those on fertile soils were all a healthy green colour.
However, warmer conditions since December have stimulated a flush of broad-leaved weeds, although he hasn’t seen any spring germinating blackgrass yet.
“If the weeds continue to grow, outstanding Atlantis treatments are worth considering, provided partner products are within limits,” Mr Hunnisett suggested.
Second wheats and later-drilled crops were due to receive their first sulphur/nitrogen dressing as ground conditions allow, he said, but applications on more forward crops would be left until March.
Neil Potts, of Matford Arable (Devon), reported that crops had generally come through the harsh winter well, having been protected by a blanket of snow this year.
“Oilseed rape canopies are variable depending on drilling dates and the level of pigeon damage,” he said. “We must adjust our nitrogen fertiliser plans according to the needs of individual crops.”
Phoma was evident in some oilseed rape crops – especially those that did not receive any phoma control in the autumn. They would be treated once ground conditions allowed, he said.
Mr Potts said Septoria tritici levels were increasing in most crops now the weather had turned mild and wet, especially in second wheats established without ploughing.
“With current high grain values, I suspect most growers will use a T0 fungicide this year to provide a good start to the septoria control programme,” he noted.
David Cairns, of McCreath, Simpson and Prentice (Berwick), said crops were looking positively healthy despite the harsh winter. “Many received an autumn application of manganese which has really helped bring them on.”
Because dry springs have been a feature of the last two seasons, he was advising growers to to apply nitrogen early on cereals, but not exceeding 40-50kg/ha.
“This is to ensure maximum tiller retention and limit the amount of leachable nitrogen in the soil profile,” he explained.
Wheat bulb fly egg hatch warnings were creeping into his area, he said, and he was recommending risk assessments be carried out on vulnerable fields to determine if an application of chlorpyrifos was required.
Now was the right time to ensure fertiliser spreader and sprayer were calibrated and ready for the spring, he said.