Recently by Neil Potts

The unusually mild weather throughout November has been a great help to all the late drilled crops in the area. With a late maize harvest there has been a significant acreage of wheat planted later than usual this year.

The vast majority of these crops have taken as little as 12 to 14 days to emerge after planting. The mild spell has also allowed later drilled crops of oilseed rape and winter linseed to put on growth and establish better before the onset of winter. Some of the August drilled oilseed rape now has such a large canopy that it now has the potential to become a management headache rather than being straightforward.

Pre-emergence herbicides have either worked really well or grass weeds are slow to emerge this autumn. I have several known brome sites where there is very little sign of  Brome emergence and certainly not enough to go with an Atalantis (iodosulfuron + mesosulfuron) or Broadway Star (florasulam and pyroxsulam) application.

This is unfortunate as the mild weather would have made for ideal timing for either of these products, which are temperature dependant for efficacy. Volunteer beans have now been controlled in many crops, particularly those established using non-inversion cultivations.

With much of the southwest wheat crop due to be planted after maize, a late maize harvest inevitably means that the following wheat is going to be late-drilled. The more favourable maize sites have only been marginally later to harvest this year than normal. But in the more marginal areas, maize crops are weeks later than last year and at worst will never make it to the target dry matter levels at all.

Second and continuous maize crops have been severely affected by maize eyespot this year. I believe that in future maize growers are going to have to factor in a fungicide application as standard practice to control this potentially devastating disease if they are intending to grow a second or continuous maize crop on a marginal site.

Oilseed rape crops range from being well established with a very high green area index (GAI) to crops that are going to need a lot of monitoring and looking after if they are going to make it through the winter. The delayed wheat harvest has meant that a lot of rape was not planted until mid-September or even early October in some cases.

The harvest, while being far from completed, has now progressed quite well on most units. Despite the very dry spell in March and April yields have held up well on all but the most drought-prone soils.

Many crops looked horrible until well into May when nitrogen that had been applied in April finally kicked in. For the second year in succession the harvest result on individual farms has had a lot to do with the moisture retentiveness of the soil, with many fields that are usually considered too wet giving the best yields.

Winter oilseed rape has yielded close to 5t/ha on a lot of farms with low biomass varieties such as ES Astrid giving yet another good showing with good ease of harvest as well. With straw prices high the rape haulm has also had a value this year which only serves to increase the gross margin on this already high-flying crop.

At last we have had some widespread rainfall with everyone getting a good soaking. Until now, the rain we have had has been patchy and showery with some getting just about enough and others getting nothing at all. The upshot of the patchy rain has been extremely variable crops with some growers delighted with harvest prospects and others disappointed by the damage done by drought

Wheat crops have remained relatively free of disease with very low pressure from septoria. I never thought I would be writing that in this part of the world. There are reports of yellow rust, particularly in Oakley, but where growers have stuck to a reasonable fungicide programme, this disease has also been well controlled.

The debate at the moment revolves around whether to apply T3s to the wheats. This decision will have been made easier by the rain. If the weather is now going to be unsettled, the main benefit of the T3 will be to prevent late ear diseases as there is no need for a late septoria top-up this year.

All the talk on farm at the moment is of drought, yellow rust and the impact on yield of both to this year's crop.

Let me first address the drought issue. Whilst there are undoubtedly pockets of ground where drought is an issue, at the moment and here, the crops are showing signs of drought stress with well waxed and rolled leaves.

But the vast majority of ground in the area I cover is not suffering from drought. The crops though have been showing signs of stress but it has been a lack of nitrogen that has been making the crops look poor.

It is not that nitrogen has not been applied, but that we have not had the rain to wash it in until recently. At the time of writing it is a fortnight since most of the area had the first significant rain in two months and this has now put right the lack of nitrogen situation.

We have had very few wet days in the last month and we are now desperately in need of rain to wash in nitrogen and to get the spring crops going. On the other hand, it has been a wonderful time for planting spring crops. Seed-beds have been near perfect and soil temperatures have been about 4-5C above the seasonal norm.

More than half the maize crop is in the ground before the usual start date for the early drillers. If maize drilling is delayed and we do not get rain, the crop could be in trouble through lack of water to germinate it. I remember maize drilled in 1976 on 8 May that finally emerged on 15 September.

Most wheat crops are looking well and are now rapidly approaching GS32 if they are not already there and will be receiving their T1 fungicide. I have not seen any yellow rust but have had a report of a crop of Oakley that received a late T0 fungicide spray that is now quite severely infected.

The vast majority of wheat and barley crops have come out of the winter looking well structured with a bigger leaf area index than we have seen for a few years. On the whole, this is desirable, but it has led to a rapid build up of foliar diseases within crops.

Wheats are showing high levels of septoria, particularly in the more susceptable varieties, and there are also unseasonably high levels of mildew present in many crops. This situation will be rectified shortly as the wheat crops start to receive their T0 fungicide applications. Where mildew is a particular problem a low rate of proquinazid will be included, Otherwise, most crops will receieve a low rate triazole, with or without chlorothalonil, depending on the severity of the septoria.

With the majority of the barley acreage being grown for feed in this area, Saffron and KWS Cassia make up the bulk of the acreage being grown. Both varieties only have a rhynchosporium resistance rating of 4. The result is that I am now seeing a lot of rhynchosporium in barley crops. In some cases this has already gone into an aggressive phase, manifesting itself as foci of really severe rhynchosporium within the field.

Crops have generally fared very well through what has been another hard winter. Our lowest recorded temperature was -17C. The main difference from last year was that the crops were afforded some level of protection this year by a blanket of snow

Oilseed rape canopies are variable depending on drilling dates and the level of pigeon damage. We have seen some very large flocks in some locations, but hopefully these will soon start to break up as we move into the spring period. This variability in green area index (GAI) for the rape crops is going to mean adjusting the nitrogen regime to the individual crop's requirement, with the smaller canopied crops receiving a bigger proportion of their nitrogen earlier in the year.

There are a few rape crops that for one reason or another did not receive any phoma control in the autumn. These crops have phoma evident in them now and will receive the treatment that they should have had in the autumn as soon as ground conditions allow.

The grain maize harvest in the region is now largely completed. Although only a minor crop there is growing interest in it as a break crop. Earlier maturing varieties with acceptable yields are a factor in driving this interest, along with more than respectable gross margins.

In most cases the following wheat crop has been successfully drilled behind the maize and emergence of these wheats has been remarkably swift considering the drilling dates. With an increase in the wheat area being grown behind grain maize it will be interesting to see if the perceived increase in fusarium risk manifests itself in these crops.

Personally I have never been able to identify a higher level of fusarium in wheats grown after forage maize, which is a common practice in this region. It remains to be seen whether the larger crop residue left after combining will provide a bigger source of innoculum. Ploughing rather than no-plough cultivations should help to keep this risk to a minimum.