Establishing next year’s oilseed rape crops and the impact of delayed drilling has been occupying the thoughts of our Crop Watch agronomists.

Prime Agriculture‘s Marion Self, from Norfolk, said oilseed rape drilled, subcast and Autocast in mid-August before the deluge, was emerging well in the friable soil structure and moisture.

Some rape establishment has been delayed until mid-September, but she was not concerned as rapeseed “can perform well as long as seed-bed conditions are good and not forced”.

With wet weather forecast, Ms Self was also delaying some planned herbicides until early post-emergence.

But good weed control could still be achieved from the various combinations of metazachlor, quinmeric and dimethenamid as most cotyledons expand before weeds germinate.

Struggling rapeseed could require some nitrogen (30kgN/ha) and applications, which if required, should not be delayed, she said.

Cereal volunteers have quickly become competitive in moist conditions and growers should aim to take them out quickly with the first contact graminicide, especially where the crop follows barley.

Slug activity has been low but growers should monitor traps and observe crops and volunteers for damage, she said.

In Northumberland, David Cairns, of McCreath Simpson and Prentice, agreed oilseed rape was best established in August, which has been possible after winter barley. But some would be sown in September around the same time as the wheat.

He also predicted a big flush of volunteers in early drilled crops and these will be taken out with propaquizafop.

“Most seed sown is dressed with Cruiser or Modesto, so flea damage is rarely seen, but I am noticing large numbers of aphids,” he said.

Some early wheats were starting to be drilled into good seed-beds after oilseed rape – and slug activity would be monitored.

Most wheat seed was being treated with Redigo Deter (prothioconazole + clothianidin) as part of an integrated approach to reduce the number of metaldehyde slug pellet applications.

In Sussex, Tod Hunnisett of Chichester Crop Consultancy, said most of the oilseed rape has been drilled in ideal conditions.

However, considering the long dry spell before the late-August rain, he was surprised by the large number of dead slugs found after a prophylactic reduced dose of slug pellets.

“There are few situations where I endorse a routine slug pellet application, but oilseed rape in a warm, wet summer is one of them,” he said.

However, he was urging everyone to follow the metaldehyde stewardship guidelines – a maximum single application of 210g/ha of metaldehyde active ingredient per crop.

Neil Potts, of Devon’s Matford Arable Systems, said the ground was only just being prepared for winter rape after the busy harvest.

Two varieties that have performed extremely well this year are both unlisted, one being Sahara and the other Lear.

Lear in particular has produced some very large yields of both grain and straw.

Meanwhile, SAC agronomist John Sarup said the rain came too late, especially in the Cheshire area, to save some potato crops destined for the chipping market, which had not achieved the right size and would have to be marketed elsewhere.

He has been talking to some clients about the use of potato blight fungicide maleic hydrazide. “I have seen good results from its use providing it is applied according to label recommendations with the crop actively growing and not under stress,” he said.