Crop Watch: Patchy emergence hinders weed control
Rain has given crops a welcome boost, but patchy emergence in early-drilled crops has made herbicide decisions challenging, according to Farmers Weekly’s Crop Watch agronomists.
Cereal drilling had progressed well in the south said ProCam agronomist Nick Brown from Buckinghamshire. Later-drilled cereals looked good and those that hadn’t been treated with Deter (clothianidin) seed dressing, would soon be treated with an aphicide, he said. But some early-drilled crops had only just chitted. “I fear a lot of seed will not come up.”
In Lincolnshire, AICC agronomist Ruth East, said patchy emergence in cereals drilled before the rain were making herbicide decisions challenging. “Some parts of fields have been up for three weeks and others have not emerged.”
But later-drilled fields emerged quickly and had received a flufenacet-based pre-emergence herbicide. Some resistant blackgrass programmes had started with a tri-allate base followed by a flufenacet-based treatment. Chlorotoluron was being applied to tolerant varieties.
Wheat was free from disease, apart from some mildew found in drought-stressed crops, she noted. “At present, high soil temperatures and a lack of soil moisture are preventing any applcations of propyzamide and carbetamide-based products.”
Very few post-emergnece products had been applied in the west due to patchy emergence, said independent agronomist Dan Dines. “The effectiveness of pre-emergence treatments in the dry is still being assessed.”
Winter rape was progressing well with some looking a bit too forward, he noted. “Crops at the 8-10 leaf stage have received a fungicide with plant growth regulator activity.”
TAG agronomist David Martindale from Yorkshire, reckoned the rain had successfully activated pre-emergence herbicides and crops were showing signs of uptake. Atlantis timing would be considered soon, he said. “But this will have to be delayed in some cases until the later emerging parts of the fields reach a sufficient growth stage.”
Slug activity had increased in all regions following the rain, but damage had been minimal to date.
Click below for the full report from each region: