3 key agronomic pointers for Scottish growers this October

Crop Progress

A lot happened during September with folk taking advantage of some better weather during the first half of the month. Harvest was still being completed – most winter wheat had been cut by the time this was written on 20 September, but there was still some late spring oats and spring barley to cut.

Potatoes had begun to be lifted, especially seed crops and probably some of the bigger ware growers will also have started.

Oilseed rape crops are in, and while I haven’t seen any myself, I’m hearing of some very forward crops. There were also some crops just popping through the ground, which no doubt welcomed the rain we had that week.

There’d been a few reports of flea beetles, but hopefully the rain curtailed attacks on crops. The biggest issue, moving forward, to smaller crops was likely to be slugs.

Cereal drilling had also started with winter barley and some winter wheats in the ground by the time of writing. Hopefully it has also been sprayed with pre-emergence herbicide.

Grant’s agronomy tips for October

1. Stale seedbeds will help

It’s never easy to get time for a stale seedbed in our region, but if you can get one before you drill it is useful. Spraying it off 10 days ahead of drilling in our trials has shown a better effect on breaking the green bridge and reducing the risk of BYDV.

Stale seedbeds are likely to be very important if you’re considering growing winter oats, especially in fields with grassweeds. As the crop is now considered a “major crop” by the Chemicals Regulation Division (CRD), our Extensions of authorisation for minor use (EAMU) for Liberator has lapsed in the crop. That leaves options for grassweed control extremely limited.

2. Drill and spray

Drilling remaining wheat fields will be a priority during October, and as I always say, if you can drill, you can roll, and if you can roll, you can spray.

Where grassweeds such as black-grass, Italian ryegrass and bromes are an issue, Liberator (flufenacet + diflufenican) + Proclus (aclonifen) is a good option for a pre-emergence spray. Just pay attention to the forecast, as while I say you can spray, if it is going to thump down with rain, don’t spray as you will give the crop a headache when it is trying to come through the ground, if you’re not careful.

But for most folk a straight Liberator will suffice if it is just annual meadow grass and broadleaf weeds. An alternative to consider is a metribuzin-containing product in Alternator Met or Octavian Met (flufenacet + diflufenican + metribuzin). These both have a new label, where the full 1.0 L/ha rate if needed, can be applied up to GS25.

These give more flexibility to when to spray allowing you to concentrate on finishing drilling, if you prefer, and taking out weeds early post-emergence, ideally around the 1-2 true leaf stage.

3. Monitor for oilseed rape diseases

Historically oilseed rape fungicides would be applied around Bonfire night but some growers have started pulling them forward a week or two to help make sure they get them on.

Light leaf spot remains the biggest risk, although our disease monitoring last year did find more Phoma in Scottish samples, albeit not at astronomical levels.

Many growers will be going through with trace elements in the autumn and maybe an insecticide for rape winter stem weevil, so if you’re going through, for the cost of a fungicide, if the disease pressure is there or conditions are favourable, it’s worth protecting the crop, especially if it is later sown and small.