Recently by Swaran Bachoo

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.

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.

 

A trying harvest is at last done. On the plus side we have had some remarkable record-breaking yields. Oilseed rape crops have topped 5t/ha and all other crops apart from spring beans have yielded as well as ever. This despite a very dry spring when spring barley fields looked like fields in a desert in north Africa and the wind that never stopped blowing, drying the soil even more.

 

Nearly all the rape crop has now been drilled and the earlier-drilled fields are at the two-leaf stage, while later-drilled fields are the cotyledon leaf stage and struggling in dry soils. We need at least 16mm of rain to wet the dry dusty earth to help small plants to grow and more importantly to let the grass weeds and volunteers germinate before drilling cereal crops.

 

This spells serious problem for grass-weed control since high dormancy has been forecast and at present there is little chitting. It will be imperative to choose the right products for blackgrass control.

 

Rain over the past three weeks totalling nearly 75mm and another 45mm in May has saved the day for most crops. Winter wheat at GS80 is now looking fairly good.

Both winter and spring barley will benefit from the rain - winter barley will have the benefit of better grain fill and in the case of the spring barley, weak secondary tillers will now be able to make a useful contribution to the yield.

Winter oilseed rape crops are at the GS6.4 stage - seed at green to brown - and will be ready for desiccation in the next 10 days. Overall, most oilseed rape crops are looking very good and should yield well.

Septoria tritici is now starting to appear on the middle leaves of some crops and mildew is obvious on many. I believe septoria is there because of the poor spraying conditions during April and May and it seems to have been a particularly bad year for mildew. I shall make sure a specific mildewcide is added to the T1 mix next season.

It is not difficult to predict weather at the moment. Dry followed by dry and dry again seems to be the order of the day. Couple this with the constant wind draining the little moisture that there is in the soil, it is a scenario for serious yield loss. We had 35mm of rain on the weekend of 5 - 6 May and another 2mm last weekend, but this is all but gone in the strong winds.

I estimate that on the thinner soils we have lost about half a ton per acre in both winter wheat and barley. With spring barley it is any ones guess. The only exception is better land where nitrogen was applied early and it caught the March rain.

Here we have four to five tillers per plant in winter barley and wheat and the crops are looking surprisingly well. On the thinner land where the nitrogen timing has gone astray the crop is single tillered. Something I have not observed for a very long time.

The dry weather is taking its toll on all crops particularly spring barley on the light ground where parts of fields are dying and have needed treatment with trace elements. Winter wheat crops are also showing signs of severe leaf tipping indicating nitrogen deficiency caused by the near drought conditions.

There is temptation to reduce fungicide rates but careful planning is required bearing in mind that there have been heavy dews at night, which is just enough to spread disease. I have a field of Warrior winter wheat breaking out with yellow rust under these hot conditions and this has a resistance rating of nine. Strange things are happening out there.

Winter wheat crops have been treated with strobilurin-based fungicide Nebula (boscalid + epoxiconazole + pyraclostrobin) to help the light land crops against septoria and guard against yellow rust. Many varieties have septoria on leaf four and the variety Conqueror is covered in mildew.

We had 6mm of rain last week and another 7mm two weeks before that. This has helped green up crops, particularly the winter barley which was beginning to look very yellow.

Nitrogen has been applied to winter barley and oilseed rape, which should start to grow rapidly now that temperatures are rising.

Winter wheat crops are carrying a lot of septoria on the lower leaves and Claire and Solstice have mildew present. As the T0 fungicide timing approaches at GS30, consider applying a triazole fungicide with a broad-spectrum activity.

Winter barley crops are at GS28 -30 and in about 10 days time should be approaching GS31 when the T1 fungicide will need to be applied. A fungicide such as Jaunt, which is based on prothioconazole + fluoxastrobin + trifloxystrobin would be a good choice.

At last it has stopped raining and with the drying wind from the north there has been frantic activity on farms. The light land is being cultivated in readiness for spring crop drilling.

 

The majority of the spring bean crop is now drilled and should be sprayed with a pre-emergent herbicide as soon as possible after rolling as there are no post-emergent herbicides available for broadleaved weed control. Where the land is ready for spring barley drilling, then carefully work out the seed rate based on the 1000 grain weight. On light land it would be appropriate to increase the seed rate to 365 seeds/sq m, but do not drill into forced seed-beds as it is better to drill a few days late rather than into wet ground.

 

Winter wheat and winter barley crops seem to be in excellent shape, albeit there are some thin areas where slugs were active in the late autumn. Both winter wheat and winter barley are at growth stage 24-26 and ready to receive the first dose of nitrogen fertiliser with sulphur. The autumn residuals have performed well, but the usual culprits, cleavers and blackgrass have come through these treatments.

Most crops have come through the winter well, although there is some frost heave in places. Where this is the case, be prepared to roll fields when soil conditions allow.

Winter wheat and winter barley are at growth stage 21-24, and winter oats are at growth stage 21. There is some tiller loss in winter barley, especially in variety Cassata.

It would be advisable to apply some nitrogen once active growth has started. This will help promote new tillers and retain existing tillers. Tiller number is all important in the barley crop for maintaining yields.

Some septoria is present on the older leaves of winter wheat crops. The autumn residuals have worked remarkably well with only little blackgrass showing through, but there are a large number of cleavers about.

All the autumn drilling, except the winter beans, is now complete. For this late drilling time, increase the winter wheat seed rate to no less than 300 seeds/sq m. The early drilled winter wheat is at the tillering stage GS 22 and the mid-October drilled crops are at GS 14. The majority of the winter barley is at the 5-leaf stage GS 15. Winter oats are at the 1-2 leaf stage.

 

The residual herbicides applied pre-emergent seem to be working well, albeit rather slowly. Volunteer oilseed rape and beans have come through the residuals and will need controlling. Since straight Mecoprop may not be used in the autumn, consider using Pixie (mecoprop + diflufenican). Thor (tribenuron) may also be used to control volunteer rape.

 

Where it has not been possible to apply a pre-emergence herbicide, or where the blackgrass has come through the first treatment, the only option is to apply Atlantis (iodosulfuron + mesosulfuron) + Biopower (Wetter) before the blackgrass gets to beyond the 3-leaf stage. The conditions at the moment seem to be ideal for application of Atlantis.