Recently in South Category

The cold weather has finally brought the GAI of oilseed rape crops back to somewhere close to where we would expect them to be at this time of year. Over the last month they have lost 0.75-1.0 GAI, which means that the forward crops are now allowing carbetamide applications to hit the ground where it's needed.

Two nights dropping to -10C have helped Fox (bifenox) to work on charlock. I was worried about how some crops going to look where there was more charlock than rape.

With the cold weather the pigeons are just starting to arrive but numbers are still far lower than we would normally expect. While the cold weather lasts I'm expecting numbers to increase. As long as they are not eating the crown of the plant they won't be doing any major damage, however be ready to control numbers before they do damage.

It's hard to believe February's already arriving. The few frosts we've had so far have done little more than steady our winter crops, leaving them thicker and lusher than we've seen for many years. What a contrast to this time last season.

Our key priority for both wheat and rape this year is clearly holding them back. A far more encouraging position than we've had of late, but one which poses its own unique set of challenges.

Perhaps the biggest of these is spring nitrogen. In the past, dare I say it, things were simple. We just altered our Nitram timings. But these days we have a serious dilemma. Mainly because we're using nitrogen:sulphur compounds which come in fixed ratios and are already on-farm, ready and waiting.

We have to get a decent amount of sulphur onto our crops early. And, recent experience has taught us the drought insurance value of early nitrogen, but about the last thing most of our crops need if they're to stay standing is early N.

At the moment I can't see us putting any fertiliser on our wheat or oilseed rape until the end of February at the earliest. At the same time, we'll probably be splitting the first dose so we get enough S on early without going over the top on the N. With the lack of individual nutrient flexibility we have these days, this is our only real option.

A quick glance at the calendar tells me it is December this week, hard to believe after the mild weather we have had recently.

Rape crops continue to race away and some are carrying huge canopies going into the winter. Soil temperatures have now declined enough to start applying Kerb (propyzamide) or Crawler (carbetamide) but given the size of some crops getting a residual herbicide down to the soil surface will be a problem. In large canopied crops we may have to wait until frosts open the crop up.

Phoma levels are low at the moment and opinion is split on the merit of adding a second fungicide whilst traveling through the crop. Aphid numbers are still high in crops and I am adding an insecticide to control these: cabbage stem flea beetle and rape winter stem weevil.

More advanced wheat and barley crops are carrying high levels of disease especially mildew. I have treated a few barley crops on light land, but I dont think the disease is worth treating on wheat crops at the moment, hopefully once we finally get some frosts this will sort the problem out.

The key observation concerning all crops this autumn has been the prolonged unseasonably mild conditions. We've had enough rain to get full germination now in all the cloddy, baked-out backward areas, but it doesn't look as if there was enough residual herbicide hanging about to be successfully reactivated. Consequently over the last week or so I've seen a considerable emergence of blackgrass in places, and follow up treatments are now becoming necessary. The good news is that the mild, growy conditions should mean the Atlantis-type follow ups should work very well.

The mild conditions have brought on an onset of disease, particularly mildew. Net blotch and rhyncho are being found in barley, along with low levels of both brown and yellow rust in wheat. I am taking note of this, but apart from the worst mildew cases in barley on thin soils, I'm not yet taking remedial action. What it means though is my early spring fungicide applications are likely to be extremely robust.

Most oilseed rape crops are growing with fury like it was spring and are at the eight leaf stage. These crops will need a PGR fungicide treatment based on metconazole or tebuconazole if not already done so. Ensure to use a fungicide that also delivers a punch of phoma treatment as, since the last seven days the risk of this disease has increased much because of the recent rains and the higher than normal seasonal temperatures.

The early drilled winter wheat and barley crops are at the four leaf stage. So far slugs have posed little or no problem, but rain has brought up these dreaded creatures and there seems to be significant damage in some fields, particularly those just emerging (late drilled fields) and where the seed-beds are cloddy.

Check crops carefully and apply slug pellets as soon as soon as conditions allow, but remember the maximum single application doze of 210g/ha and 700g being the maximum dose per calendar year for metaldehyde.

Oilseed rape crops are romping through the growth stages with some very large canopies present. The warm conditions are suiting the crop rather too well. Even so, I was rather surprised to find DK Cabernet, drilled at the end of the second week in September, already over 30cm tall.

The dry conditions have slowed the spread of phoma significantly. South of Oxford, the disease has now come into the crop and I have applied a fungicide/aphicide mix. But further north, phoma is still absent and I am holding off for the time being. 

Unfortunately, the dry conditions have conspired against decent pre-emergence weed control in cereals. All sorts of problems are evident, some crops have a carpet of blackgrass in them and swathes of volunteer rape, which indicates just how little activity the herbicides have given.

After an awful summer we moved into a very dry and unusually warm autumn drilling season. Consequently the winter crops went in to very good conditions and many growers have finished earlier than expected. There are a few winter beans to go in but generally speaking everybody seems to be wrapped up. Most emerged crops look very well but some later-drilled crops on heavy ground are still struggling for moisture.

Pre-emergence herbicides went on in less than ideal conditions, with varying results. A few millimetres of rain a few days ago appears to have reactivated them, so in most cases I'm not rushing in with post-emergence follow-ups just yet.

Winter rape, after a slow start, took off with vengeance in response to the warm weather. Now all crops look very healthy, some would argue too healthy, but this is a problem I actually like. I've seen very little phoma and with some crops up to welly-boot level I think the risk is minimal this year.

Things have changed little since my input last month - the dry weather has continued except a few millimetres of rain a couple of weeks ago.

Early-drilled crops with roots in moisture are growing well, albeit rather slowly, but later cereal crops drilled in the first week of October are standing still and starting to struggle. Rain is forecast for this week and this should restart crop growth before any frosts come.

In the majority of cases, autumn residuals have worked remarkably well despite the dry weather. However, there are some instances where large numbers of blackgrass plants have appeared in the treated fields and will certainly need another mid-season herbicide treatment.