Published on 30th October 2023
Potential agronomy jobs if weather allows in November
Tom Sowerby assesses what could need doing, weather permitting, in November
October became grimmer as the month progressed, culminating in the floods following Storm Babet. Parts of South Yorkshire and a decent amount of land around York has been underwater so it’s not been great.
Maybe around 70% of the wheat had been drilled but a significant chunk of that went into less-than-ideal conditions. Currently it’s not looking great for getting the rest in this side of Christmas, but maybe with some fair winds and frosty, dry weather land may become trafficable again.
Tom’s agronomy tips for November*
*Subject to being able to do fieldwork
1. Weed control for November drilled wheat
It’s probably a big “if” this one, but if you’re able to get wheat drilled in November, then weed control will also need considering, especially where there are expected grassweed issues.
Obviously later drilling should mean lower numbers of grassweeds coming up in the crop, assuming you’ve been able to spray off land pre-drilling.
But where you know you have either black-grass or Italian ryegrass challenges then I would be erring of the side of caution and using Liberator (flufenacet + diflufenican) + Proclus (aclonifen) pre-emergence. I’ve seen where people have cut back a bit and it’s not been great.
Just be careful with seedbeds when applying any residual herbicide, making sure seeds are covered with 32mm of soil and slots closed properly.
2. Weed control for October drilled wheat
Feedback I’ve received suggests a decent amount of October drilled crops did receive a pre-emergence spray. Applying a top up might not be the highest priority, particularly if you’ve still got drilling to do, so it will probably be on a case-by-case basis.
We’ve had a label change for this season for both products, which can now be used up until GS25 rather than having a cut off at the end of November, and at the full rate of 1.0 L/ha. That’s made both much more flexible options.
If you didn’t manage to get a pre-emergence or any residual herbicide on to October-sown crops, then the urgency is obviously higher. The metribuzin products are options in this scenario too, but you could consider adding in Atlantis OD (mesosulfuron + iodosulfuron) if grassweeds have 2-3 true leaves. It does limit your options in the spring, but if you can travel now, it’s easier to control smaller weeds than firefight in the spring.
3. Is it worth applying an autumn fungicide in oilseed rape?
Oilseed rape in Yorkshire has been a struggle this year with both high slug pressure and adult cabbage stem flea beetle attacks. The week of hot weather in September coincided with quite a lot of crops being at a vulnerable stage and they got hammered that week.
The outlook isn’t particularly great for some of these crops, which means it’s probably worth waiting and seeing whether the crop is going to survive before committing more money to them.
If you have better crops and either or both Phoma or light leaf spot are going through the roof then that’s when an autumn fungicide is more justifiable. Options include Proline (prothioconazole) or Aviator (bixafen + prothioconazole).
4. When to terminate cover crops?
Cover crops generally look pretty well, where they are being grown. The warm September and decent moisture levels has helped get them growing.
Generally I would be looking to terminate them around five to six weeks ahead of intended spring crop drilling dates. Obviously depending on species in the covers some might be more controlled by frosts than others, and there are also options for grazing and rolling on a frost to start termination.
But even if you’ve grazed or rolled you’re likely to still require a dose of glyphosate to finish them off, as well as if you’re just using the chemical approach.
Rates could vary depending on species present, grassweed pressure underneath and previous management, but keep rates appropriate to the situation, and remember some species are more difficult to kill off, such as vetches and lucerne.