Winter’s much heralded arrival this week is very welcome. Let’s hope it’s a real change to colder conditions and not just another weather wobble.
A run of cold nights and days and it won’t be long before soil temperatures will be right for propyzamide, which should work well with all the moisture we have in the ground. We won’t be rushing in, though.
We’ve more than enough blackgrass to deal with in our oilseed rape, but clethodim did such a good job that most is small and not that competitive. We have plenty of time to hit it hard, so we’ll wait for the winter to open up our generally well-grown crops for the best spray-to-soil contact.
With phoma levels building rapidly in susceptible rape varieties over the past 7-10 days, we won’t be waiting for propyzamide time to get a good dose of fungicide onto the OSR that wasn’t forward enough for an early metconazole spray. After struggling for spray days in the wind and rain some colder, calmer conditions will certainly be welcome.
They should really help us where charlock is proving troublesome too. As well as giving a much needed boost to control from bifenox, the cold will be valuable in hardening crops against its collateral damage.
Wintery conditions should also reduce the cereal barley yellow dwarf virus (BYDV) threat. With plenty of winged aphids about, we gave any wheats emerging by the end of September a timely pyrethroid follow-up to their Deter (clothianidin) dressings in late October/early November. The weather may be sufficient to make this unnecessary for our October-emerged wheats, but only if it stays cold for a good two weeks. We’ll be watching things carefully as we don’t take chances with BYDV.
We haven’t been taking any chances with blackgrass this season either. Avoiding early drilling and using very robust pre-emergence herbicide programmes has been invaluable on our higher risk ground. Any weeds that have come through are still small and should now be well held back by the cold – providing it’s not just a flash in the pan.
If ever we needed proof of the value of multiple stale seed-beds, this season has provided it in spades. Some of our fields were sprayed off with glyphosate three times and have shown incredible repeat black-grass flushes.
To make the most of this opportunity, I have no doubt later drilling is something we’re going to have to embrace as part of our grass weed control strategy. To hold our nerve here, it will be vital to maintain the greatest possible flexibility in our establishment systems; not least to ensure we’re able to get our crops into seed-beds that give them the best possible start and can take a good pre-emergence application.
It’s a battle of wits, but we’re still waiting to drill the last second wheats on our highest risk fields. We’re not worried yet, but this is another reason it’s good to see the cold weather arriving. As it is for our primary cultivations ahead of spring barley.
All round, here’s wishing for a really good winter!