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South: Less haste when writing off crops

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Don’t get too hasty to write off drilled crops yet. Many are far better when you walk across them, than they look from the gateway or headland. The photo below is a classic example.  Yes it looks like a very good field of wheat, but it has been so wet that the volunteer cereals were only sprayed out mid-November.

Once you start looking through the oilseed rape there are 40+ viable plants per square metre. As they were drilled at 55 seeds per metre establishment has been good (about 80%). Yes, there are some areas of the field that are much lower, but the average is good. At the end of winter 20-30 plants, managed well, can yield as well or better than a lot of thick crops.

Fieldofwheat.jpg

 

Typicalplants.jpg

The second photo shows that the typical plants are not particularly small, but they are smaller than we would expect for this time of year. As long as we can keep the pigeons and slugs off them, they should survive the winter. A good covering of snow would probably help.





What is interesting is that a lot of the “good” fields haven’t got any more plants per metre square than some of the smaller crops. Yes, there are more plants at 6-7 leaf stage, but there are probably 50% which is typical for the year. Believe it or not, but the photo below has the same number of plants as the first one and most are at 3-4 leaf stage.

 

Visible phoma levels are lower than expected, but most untreated crops are at threshold level, so fungicide applications are urgent. Crops which have been treated now have very little or no visible active phoma. If weather allows I would still recommend treating again, about six weeks after the first application. Very few crops need a PGR, so I’m sticking with Capitan (fluzilazole).

Phomalevels.jpg

One big advantage for this year has been that because cereals have been drilled at least a month later than normally expected, the grassweed levels in a lot of places are far lower than normal. Oilseed rape crops have often looked like a carpet of grassweeds, but on some untreated wheat it is nearly impossible to find blackgrass.

There are exceptions, so some fields will need autumn Atlantis (iodosulfuron + mesosulfuron) if weather permits,  but there are places where we are questioning whether we will need any at all. This will depend on what spring germination is like, but there are blocks of land where we do wonder why we insist on drilling in early to mid September. Would late-September or early-October be possible, as it would allow more stale seed-bed treatments and reduce the level of blackgrass and brome in crops?

At the moment, if weather permits, I am still recommending that grassweed pre-ems are still applied from an anti-resistance policy. If blackgrass has still to germinate I would use a flufenacet based programme, but if blackgrass is visible then either some Atlantis or Auxillary (clodinafop + prosulfocarb) will need adding depending on resistance status and weed size. BYDV is still a threat some and an aphicide will be needed as well.




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