What an exceptional autumn this is proving. Drilling is virtually complete except for wheat after the last few maize crops. Seed-beds are generally of good quality, however, knobbly areas on heavier soils are showing slow emergence. Poor seed-to-soil contact is the culprit, aggravated by slug activity where there is air space between soil aggregates. These areas are showing low efficacy from pre-emergence herbicides.
Inevitably, with the decline in activity of post-emergence materials, these areas will have blackgrass next spring. Thankfully these problems are isolated and have not spoilt the party too much. Many held off drilling as long as they dared, but when mid-October passes it is very hard to keep the drill in the shed.
Next week’s weather looks unsettled. If you have emerged blackgrass in wheat, take any chance you have to apply contact materials. Apologies to readers further east, but ALS materials are still giving reasonable control over here.
We are seeing big benefits from mixing glyphosate with pre-emergence treatments, particularly in non-plough situations.
The annual do we, don’t we season for propyzamide has now started. There is always a temptation to go earlier if Phoma is an issue. My advice is to treat every problem on its merits. If you have phoma above threshold then spray it now when treatments will be most effective. If you need to treat for blackgrass, then wait until conditions are right or you will be disappointed. Sprays for light leaf spot can be combined with timely propyzamide applications.
One or two areas of oilseed rape which were redrilled following severe slug damage despite pelleting have established well and should make it through the winter.
Earlier treatments of clethodim or carbetamide look to be effective. Only time will tell which is the most successful. Clethodim has had a far better season than last year when dry conditions reduced efficacy. Guidelines suggest that clethodim needs to be applied by the end of October (mid-October for early flowering varieties), so next week is your last chance.
The more I see of Clearfield rape crops, the more I like the system. Many of my worst charlock fields would now be a blaze of yellow with “normal” chemistry. Couple that with excellent volunteer control and the case for looks very compelling. We are into our fourth season on some farms and so far, the worries about uncontrollable Clearfield volunteers look unfounded.
Winter barley has established well. All herbicides have been applied pre-emergence. The worst areas have received tri-allate followed by flufenacet/flupyrsulfuron pre-emergence mixes. In recent years we have seen precious little blackgrass activity from post-emergence treatments in barley. We will save them until the spring for wild oats.
Winter bean drilling started last week. Most crops will be ploughed down and then levelled by rolling or light cultivations. Experiments on farm with homemade bean drills using modified subsoilers have been effective. The reduced soil surface disturbance means fewer weeds and the subsoiler leg gives the bean a channel of tilth in which to grow. Clear up any surface greenery with glyphosate in the pre-emergence period.