The hot dry weather in September has caused many questions to be raised about crop management. Much of the wheat drilled in early to mid-September went into excellent seedbeds. As soils have dried since then seed-bed quality has declined but pre-emergence herbicides have continued to be applied unless seed coverage has been inadequate.
Some farmers are now waiting for rain before continuing to drill. If seed is going to be sown into dry seedbeds then seed rates should be based on likely emergence date and not on drilling date.
Where bad blackgrass fields have been left for slightly later drilling blackgrass has been emerging, allowing a proportion of the population to be burnt off with glyphosate before drilling. I suspect the main flush will occur when we eventually get a decent rain.
Where cereal crops have emerged and seed hasn’t been treated with Deter a foliar insecticide is due to catch the first migration of aphids into fields. These warm, settled conditions at the time of writing are ideal for aphid movement.
Where possible any post-emergence herbicide use (especially programmes based around CTU co-forms) will be delayed until crops have hardened off a bit and the unseasonal weather has passed.
The main benefit of these dry conditions is that slugs are not generally causing too many problems, thanks to a bone-dry soil surface coupled with excellent seedbeds. However, it is worth monitoring closely in cloddy areas and on dewy/misty mornings.
Oilseed rape varies enormously. Earlier-drilled crops have had a PGR fungicide to regulate growth and in some cases protect against early phoma. Some of the later-drilled crops are on the thin side but where populations are adequate are now getting herbicide plus insecticide.
Leaf miner can be seen in most crops – insecticide treatments are being applied to restrict further damage on new growth as the weather continues to encourage the pest.
Where blackgrass needs treating in rape, options are limited especially if fop/dim resistance exists. Soils are far too dry and warm for an early application of carbetamide where the plan is to sequence it with a later application of propyzamide. It may have to be a case of being patient and waiting for more suitable conditions or using a much later applied mixture of carbetamide + propyzamide.