Our agronomists are considering field recommendations for the final treatments of the calendar year
With their planned area of winter cropping safely in the ground and herbicide applications having mostly gone to plan, our agronomists are considering field recommendations for the final treatments of the calendar year. Dominic Kilburn writes.
Notts and Lincs
Following a good October for drilling, most growers have drilled what they wanted to, said Nottinghamshire-based AICC and Arable Alliance agronomist Andrew Wells speaking on the 9th November. Maize harvest, however, had caused some drilling delays with crops not reaching the stage maturity required by growers.
Andrew commented that, in general, black-grass control in wheat had gone quite well, with more growers intentionally delaying their drilling to gain better control.
“With the benefit of hindsight, some could have delayed another 10 days or so as a later flush of black-grass came through with the early to mid October-drilled crops and a lack of moisture during that month reduced the initial effectiveness of the pre-em stack.
“Early November has seen an increase in rainfall and the pre-em actives have started to work better, but it will be imperative to get the post-emergence application on pre-Christmas to reduce black-grass numbers further,” stressed Andrew.
He said that Atlantis or Horus (iodosulfuron + mesosulfuron) will still be the mainstay of post-em treatments on wheat but prosulfocarb tends to be the product partner of choice, providing more consistent activity than other partners.
“I haven’t recommended the use of prosulfocarb at any pre-em timing,” he added, pointing out that some growers will put flufenacet + pendimethalin in the post-em mix depending on which weeds are coming through.
According to Andrew, the oilseed rape area is down slightly in the region, but not significantly and there have been no real problems with flea beetle in his clients crops.
Clethodim herbicide applications that were applied two to three weeks previously appear to be giving good, but not perfect, grass weed control and propyzamide recommendations have been made, ready for applications from late November through December – a month’s window of opportunity if soil temperatures cool sufficiently, pointed out Andrew.
At the time of writing, no phoma thresholds had been met in clients’ crops and so planned propyzamide treatments will be tank-mixed with a fungicide for phoma control this autumn, with Andrew suggesting that due to the large size of many crops and the late appearance of phoma, yield responses to autumn fungicides would be small this year.
In terms of growth regulation, and despite some crops already being at knee height, Andrew said that he’ll wait and see what the winter, and then pigeons, bring before making any decisions. “If we can manage crop height by nitrogen timings and tebuconazole in the spring, rather than a PGR now, then that will be the preferred option.
“The aim is not to have to spend money if you don’t have to,” he concluded.
Likewise in the west of England it’s been a “fairly kind” autumn, said Herefordshire-based Hillhampton Technical Services agronomist, Antony Wade, who reckons that most of what was planned to be planted was now in the ground with the exception of some wheat following late harvested maize. Also speaking on 9th November, Antony suggested the recent rainfall would mean that a spring crop would now likely follow any maize that remained.
“Early planted wheat, oilseed rape, barley and oat crops are all sprayed up with residual herbicides, but on later planted wheat where annual meadow-grass and broad-leaved weeds dominate these will be taken care of this side of Christmas if we get a weather window, or in the spring with contact chemistry,” he commented.
“We just need to get a fungicide on the OSR with phoma having only just reached threshold levels. I’ve held on to be able to do a single spray in the autumn – using penthiopyrad + picoxystrobin (as in Frelizon or Refinzar) for light leaf spot and phoma control as well as for root enhancement for slightly backward crops, but for varieties such as Charger that are weak on LLS, then they’ll get prothioconazole.”
Antony said that he’d been wondering whether growers would be able to combine OSR propyzamide treatments with the phoma fungicide but warm temperatures have put paid to that.
“We will need to go with a separate spray for propyzamide in December, which is often the case,” he added.
According to Antony, the exceptionally mild and moist weather in the first part of November has meant that slug activity has increased and pellets will have to be applied to some of the October planted wheat. These will be ferric phosphate-based now to avoid metaldehyde losses into watercourses in the wetter conditions.
Cover crops are increasingly popular in the region, he said, as growers look for increased nutrient capture as well as to address issues with soil erosion on over-wintered stubbles.
“They are certainly the buzz word at the moment and a lot of people are interested in them. The ones we planted went in the ground in early September following wheat ahead of spring cropping. Sowing date was later than ideal but in what has been an open autumn, they have established well. A black oat and berseem clover mix was selected for nutrient capture, soil structure benefits and reducing overwinter soil erosion, but also being easy to destroy in the spring.
“My concern this year is for those fields left undrilled after late-lifted maize. In this area nutrient loss in rivers is a key issue and it’s very important that growers realise the soil erosion and nutrient loss that occurs over winter and that they try and do something about it. They must comply with the standards of Good Agricultural and Environmental Condition (GAEC),” he reminded readers.
*Antony can be contacted on 07973243590 or on Twitter: @HTSagronomy.