Farming News - Concern over small canopies in backward oilseed rape
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Concern over small canopies in backward oilseed rape
03 May 2013. Some sunny days have improved the appearance of most crops but growth is still ponderously slow for the time of year. The forecast for a cooler than average May suggest that leaf emergence in cereals will continue to be slower than usual. Disease levels remain low with Septoria being the only pathogen being recorded in most wheat crops. Winter oilseed rape crops are also behind with only a few crops having an overall yellow appearance. There is growing concern over the many backward crops which are failing to produce any significant side shoots. Pollen beetle numbers remain low although Seed Weevil has been found in the South. Spring cereals are emerging well.
- Pollen beetle levels remain low
- T1 for early sown winter wheat crops.
- Oilseed rape first flowers appearing.
- Check for Club Root in slow to grow crops.
- Mouse damage in Sugar Beet.
Bayer have a useful tool for predicting pollen beetle migration click here to view.
Winter Wheat
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Septoria still the only disease present in most crops. |
South. September and early October sown wheats are beginning to extend rapidly and now range between GS31-32 with leaf 3 up to 30-50% emerged on Cordiale, Solstice and JB Diego, with leaf 2 starting to emerge on Gallant, and leaf 4 up to 50-75% emerged on Claire, Scout and Grafton with the tip of leaf 3 emerging on main shoots. Otherwise most later sown crops are now in early stem extension around GS30-31 with the tip of leaf 3 starting to emerge. Crops sown in January/February are still at tillering. All T0 sprays been completed in conjunction with a reduced rate early PGR to try and reduce apical dominance and retain as many tillers as possible. T1 spraying now underway on all crops that have leaf 3 2/3+ emerged.
Septoria tritici: September sown Cordiale and Scout are showing high levels of infection on leaf 5 and below, otherwise most wheats are only showing fairly low levels of infection on the lower leaves. T1 applications being based around Proline or Tracker with Chlorothalonil added to all mixes – more rust prone varieties and second wheats are also having Amistar included.
Slugs: some renewed foliar shredding seen in crops on heavier ground after oilseed rape with adult slugs readily visible on dewy mornings.
Weed control: all unsprayed fields requiring blackgrass herbicides have now been sprayed and so far control looks promising. Brome levels are much lower this year.
Eastern Counties. Just a year ago, we’d started treating the emerging third leaf of wheat crops in mid-April. This spring, with our earliest fields of Gallant or Solstice showing just the tip of leaf three a few days ago, T1 applications will go on from somewhere between 6th and 16th May. So we are fully two or three weeks behind last year. Fields are dry but with moisture under the surface. It has been warm dry and windy with cold nights and the odd frost.
Septoria tritici: trace levels on lower leaves.
Yellow rust: reports of some crops of Torch infected.
Eyespot: can find stem based browning but difficult to diagnose as eyespot.
Weed control: where pre ems were used we have had good blackgrass and broadleaf control.
East Midlands. Many crops at leaf 4 stage with a few forward ones with leaf 3 tip just showing, which puts T1 at 7-10 days away. Cold nights have slowed growth and many crops seem to “lack get up and go” February drilled crops at 3 leaf to early tiller. Shallow rooting of many crops a concern if dry weather continues for next 2 weeks as forecast. Forward crops have had T0 and expect T1 in about a week or so on forward crops – late drilled crops will have a joint T0/T1. It is hard at present to see any great need for SDHI at T1 and most sprays will be based around Mantra on lower potential crops or Tracker on eyespot crops + CTL.
Septoria: Older leaves dying off and new green growth showing no major infection. T0 gone on better crops or septoria weak crops this week.
Yellow rust: none seen.
Eyespot: levels remain low with just the odd plants showing stem browning.
Weed control: in late drilled crops weed levels remain low and will be tackled at T1 – suspect if we get rain a flush of weeds will follow so not looking to go in too early.
West Midlands. Although we've had some warmer days crops are still reluctant to put out new leaves. Final leaf three visible in most crops sown before mid-September but for the bulk of crops leaf four is the most recent leaf to emerge and T1 will be timed towards the end of next week. Crops have been wet in the early mornings from heavy dews. Some signs of plants suffering on light land from lack of rain. Late sown (February) crops at two to three leaf stage. T1 fungicide choice will be mainly Tracker + chlorothalonil or Firefly, only a few promising early sown wheats will get Aviator at T1. Second wheats will get Fandango.
Opomyza: tiller death from yellow cereal fly larvae are more obvious this year than for some time.
Mildew: trace levels in base of crop on forward Humber, otherwise crops remain free of this disease.
Septoria tritici: very evident on the forward crops, whatever variety, none on new leaves.
Yellow Rust: no fresh sightings.
Fusarium/Eyespot: symptoms have diminished in the dry conditions.
Weed control: herbicides applied ten to fourteen days ago beginning to work but not helped by the dry conditions and cold nights.
North East. Most wheats now stem erect, with forward crops at or approaching GS 31 The average temperature for the week was 9.3 degrees. Tillering on healthy plants is good. There was 5.2 ml rain over the week. but it has been a windy dry week drying fields further. Average daily temperature for month of April was 7.7 degrees. T1 to start this week on most forward crops.
Septoria tritici: active on lower leaves of some varieties but not moving up the crop.
Yellow rust: none seen.
Wheat bulb fly: low levels in some crops.
Weed control: warmer weather bringing out early spring weeds.
Winter Oilseed Rape
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There are a lot of spindly crops about. |
South. Finally, even the most pigeon ravaged crops are beginning to look vaguely green again – perhaps there will be something to combine after all. The most advanced and ungrazed crops are now typically between Green bud and early flower within the same field.
Club root: one field seen recently, that has had no previous history of club root, but now has around 75% infection of all plants. Suggest that any fields/patches not growing away strongly in the next week or so are investigated for club root symptoms.
Light leaf spot: dried up lesions of infection controlled by recently applied fungicides can be easily seen older leaves in crops that had been relatively ungrazed.
Sclerotinia: crops at yellow bud/early flower will have Proline + mbc mixes in next 7-10 days to provide sclerotinia protection.
Pollen beetle: still only finding low levels of adults – up to 2 beetles per plant now in places.
Seed Weevil: first adults being found now in areas of flowering rape. It could be a bad year for weevil with the variable flowering and warmer ambient temperatures now that we are into May. Mavrik with sclerotinia sprays where required.
Eastern Counties. Forward crops have moved into flower but with a return to cold nights and a cold wind backward crops have slowed up again especially so on heavier soil types. So many of the backward crops are still looking very spindly and are at green bud. There have been some variable showers about but generally sufficient to help wash nitrogen into the soil. Drying conditions now and for the immediate future.
Light Leaf Spot: Some Proline applications being made for low levels of LLS in backward crops which received no autumn fungicides taking the opportunity to add boron and other trace elements where required.
Sclerotinia: planning flowering sprays for sclerotinia around an anticipated shorter flowering period. Will try to be on the early side targeting early flower where no previous spring fungicide has been applied and then make the decision re a second flowering spray depending on weather conditions.
Pollen beetle: levels have risen slightly to maybe 1 or 2 per plant in places but no treatment recommended at present. Still cold for pollen beetle activity.
East Midlands. Some crops showing a spurt of growth but many still only just at green bud and short – side shoots are there but will they produce anything is the main question especially if it remains dry. Final N aimed at yellow bud when decision will be made on final amounts depending on how crops look. Spring rape drilled with some variable emergence reported where heavier soil in fields.
Light leaf spot : very little seen.
Pollen beetle: just one or two pollen beetle seen and generally non existent so far and cooler weather this weekend will slow them down.
Weed control: control now complete.
West Midlands. Forward crops slowly putting out more flowers. Noticeable patches of flowering crop where bird scareres have been. Still a lot of backward crops about which are slowly beginning to bulk up and put on height albeit rather slowly. These backward crops have worryingly few flower buds developing and to date seem reluctant to produce any significant side shoots to compensate.
Light leaf spot: no obvious signs yet. Proline being applied since mid last week to crops that have been looked after, most will probably go beginning of next week
Pigeons: still present but in fewer numbers.
Pollen beetle: still hard to find but backward crops need monitoring.
Sclerotinia: fungicides to go on at early to mid flowering.
Weed control: flush of groundsel and field pansy coming through in pigeon damaged crops. There are going to be some dirty crops come harvest this year.
North East. Most crops now at Green bud to early flowering, with forward crops pushing ahead well. However, very backward crops looking spindly and budding before good development of stem and leaf.
Pigeons: becoming less of a problem.
Pollen beetle: odd one seen in green bud.
Light leaf spot: low levels only.
Weed control: wild oats starting to emerge. Odd thistles being controlled.
Winter Barley
South: most advanced crops are now at GS30-31. T1 applications underway or now completed.
East: crops continue to improve. Some are very thick and most advance now at GS 31. Disease levels remain low but watch out for Brown rust.
East Midlands: Crops approaching GS 30. Final N will go on in about 7-10 days depending on growth. Disease levels remain low.
West Midlands: Most advanced crops now at GS 31-2 but they are shorter than expected. Disease levels remain low.
North East: Crops moving on and most forward now at GS 32. Very little disease present. Good tillering generally. Spring barley up to GS 11 but dry weather continuing to delay germination in odd spring crop.
Sugar beet
We are still generally seeing the pattern that generally April drilled beet have a more uniform emergence and better overall plant counts than March drilled beet. A few patches / fields have been re-drilled after wind blow on light sands and frost damage on the fens. Otherwise we are leaving fields with poor emergence as we have plant populations in the region 45 to 50,000 per /ha, a few seedlings are still emerging some 6 weeks + after drilling. Rumours are afoot that one variety has shown poorer emergence than others. This is being followed up but Pat Turnbull believes the poor emergence is related to the cold soil temperatures at and after drilling and has been seen in several varieties. The mouse damage on some March drilled fields has also been substantial.
I am hoping we have now had sufficient moisture to help the more recently drilled seed in dry soil ( cloddy areas of fields) to germinate and emerge.
Some of the more vigorous beet now has the first true leaves appearing, just hope the bird grazing which has started, is not too severe.
Weed control continues apace, there is a good flush of weeds on most soils , first FAR sprays have been applied with the next due after 7 days. Most beet fields have now received or are just about to receive first post-em herbicide ( conventional systems rather than FAR)