27 February 2012: The cold snap has helped curtail disease development in many wheat crops but they will need careful monitoring now that milder conditions have returned. Blue patches in crops of oilseed rape are common but these should recover quickly with milder weather.
Fertiliser: applications on oilseed rape starting
Yellow rust: in east and south - keep monitoring.
Brown rust: in east, south and north - keep monitoring.
Mildew: levels declining.
Winter Oilseed Rape
Phoma lesion in oilseed rape (Photo courtesy of Farming Online)
South East: All crops now at late rosette to early stem extension - fields with low N status have gone very purple in appearance following frosty spell. First N+S being applied to most crops now but holding back until March on strongest/greenest looking crops.
Cabbage Stem Flea Beetle: only very low levels of cabbage stem flea beetle larval invasion been found and only in low number of crops.
Phoma: no significant renewed spotting seen to date.
Light Leaf Spot: none seen.
Weed control: Charlock and Runch - there were heavy populations in some fields, though most is now nicely browned by recent hard frosts following earlier applications of herbicide.
Eastern Counties: Lighter land crops have lost some larger outside leaves during the winter, crops on well structured heavier soil types have maintained leaf and colour. Crops are generally well advance and giving good ground cover, some have excessive foliage and are quite tall others have remained more prostrate and closer to the ground. Will be assessing GAI nearer to timing of first N and making allowances for N already in the canopy.
Phoma: no new infections seen.
Pigeons: more of a problem in some crops drilled on wider rows.
Weed control: Charlock well controlled by frosts.
East Midlands: Colder weather and frosts have knocked crop back a bit but not to a great extent, but some crops with blue leaves still. Many crops will have Bittersaltz with first fungicides as magnesium deficiency envisaged. Crops vary greatly from GAI of 1.25 up to 3.5. With crops looking well and plenty of growth no rush to put N on but need for sulphur will dictate need for some early N, if mild weather may split the first dressing to ensure some sulphur is applied, and hold bulk of N until early flowering. Crops with low GAI of around 1 will get normal split dose early March.
Phoma: no new phoma seen with older leaves dying off
Light Leaf Spot: little seen but some leaves incubating in bags now to determine whether LLS or not. Lot of crops have various leaf damage from frost, herbicides etc making LLS lesions difficult to distinguish.
Weed control: Charlock and runch well hit by frosts
West Midlands: Crops range from 10 true leaves to early stem extension. There are some very blue patches in some crops after the frosts. N + S applications starting on backward crops this week weather permitting (splitting sulphur dose into two applications) remaining crops end of next week/1st week of March.
Pigeons: Just beginning to come into some crops - big flocks around.
Phoma: no new infections.
Light Leaf Spot: Some crops show signs of LLS however, these fail to develop when incubated suggesting that the symptoms are a sign of the frosts rather than disease.
Cabbage Stem Flea Beetle: a few larvae have been found in the leaf petioles in some crops.
Weed control: runch and charlock control by frosts looks impressive but poppies still present.
North East: Crops are still very big but much more open than last November. Crops are in the range of 7-12 leaves. Some crops looking a bit untidy now after some damage by the cold spell. Patches have taken on a temporary blue appearance, but they will green up quickly in the warmer conditions that are forecast. Several crops have been assessed for GAI and range from 0.5 to 2.5. It seems that with the change to wide row spacings following the popularity of the sub-soiler for drilling estimating GAI is more complicated. It looks as if cutting and weighing might be the only way to get an accurate figure.
Light Leaf Spot: the conditions so far have been conducive to LLS development, but no symptoms are evident in crops seen so far, and this included Dimension.
Phoma: no further infections seen.
Weed control: Patches of Runch and Charlock have been severely checked by the recent frosts.
Yellow rust in winter wheat (Photo courtesy of Farming Online)
South East: Following very cold conditions in the first half of February, crops are looking a bit ravaged by sharp frosts (down to -11C) and cold winds. Crops range from early tillering (late October+ sowings) to late tillering, GS 29 (September sowings). First N+S Applications now being made to second wheat and crops sown after oats/linseed and maize.
Brown rust: recent sharp frosts have reduced foliar symptoms, however pustules can still be found in areas with thicker canopies, particularly in September crops of Claire, Cordiale and Solstice.
Mildew: High levels were present in many earlier sown fields of Solstice, Gallant, Claire and Cordiale, but pustules have been browned up by sharp frosts.
Yellow rust: hard to distinguish early pustules from brown rust, no foci seen in last 2 weeks.
Weed control: where present blackgrass is now at GS 21-24 and will be sprayed with herbicide in next 2 weeks now that soils are warming again. However, fields where herbicide applications were delayed until Spring 2010 and had poor resultant blackgrass control, are now exhibiting quite high levels of blackgrass plants unaffected by herbicide(only 50-60% control in some cases).
Eastern Counties: Currently, cereal fields appear reasonably green, with many not looking in the least hungry.
Brown rust: easily found in some crops. Varieties include Claire, Grafton, Hereford, Santiago and Invicta.
Yellow rust: quite a lot of rust in Oakley and Robigus, low levels in Viscount.
Mildew: most crops exhibiting fair amount of disease.
Weed control: good autumn control of blackgrass but some cases with resistance. More cleavers around than last year.
East Midlands: Little or no change with many crops looking a bit purple after cold weather but all crops continue to look well, with many at GS 24/25 with very forward crops just starting GS 29. Some crops leggy but still at GS 25. No N envisaged yet although some second wheat will require N soon. Manganese patches continue to be a problem.
Brown rust: none seen.
Yellow rust: none seen.
Mildew: cold weather has held it at bay, but plenty of old pustules showing mildew is ready to go again when weather warms up, particularly on Solstice. Any high levels of active mildew in February may require an early T0.
Septoria: plenty of usual septoria on older leaves shows risk is high
Weed control: with return to milder weather herbicide to be applied when it is certain blackgrass growing probably early next week if weather allows. Some fields showing odd blackgrass after autumn herbicide.
West Midlands: Early sown Solstice and Grafton with main stem at growth stage 30! A lot of crops with as many as 6-7 tillers. However, majority of crops are not too forward BUT will be in need of PGR by the end of March. Still no significant rain in the region and concern growing over drought like conditions. Near empty reservoirs on some farms.
Brown rust: none seen
Yellow rust: none seen
Mildew: the last lot of frosts have put paid to mildew for now.
Septoria: lots of Septoria in the base of many crops.
Weed control: wild oats are easily visible in most crops where you would expect to find them and Bromes more visible than last spring with some already at a reasonable size with 3-4 tillers. Some impressive patches of cleavers after oilseed rape.
North East: All early sown wheat crops are fully tillered in the range of GS 24-27, and they are also well grown with full ground cover. Later sown crops are at GS 22-24. It is still unusually dry, and only 5mm rainfall recorded on last 14 days. There are ditches 2 metres deep carrying no water, if a dry season follows this will be detrimental even to crops on our well-bodied boulder clays. The recent cold spell seems to have cleaned crops a bit but there is still a major amount of infection out there that will need to be controlled when temperatures rise. First applications of 65-85 kg N are planned now on second and continuous wheats. No applications are planned for first wheats until mid-March.
Brown Rust: low levels seen in the most susceptible varieties, such as Duxford and Grafton.
Yellow Rust: Some heavily infected plants seen in some early sown Oakley.
Mildew: only the most resistant varieties are clean such as Warrior and Viscount. All the rest have varying levels of infection.
Weed control: Autumn applied herbicide seems to have done good job in most situations, with no obvious advantages showing for any specific tank-mix partner. There are a few fields with poor control. A more robust post harvest cultural program is all that can help these situations. More fields are being identified now that were not sprayed in the Autumn, but have enough blackgrass to justify treatment.
South East: Crops now range in growth stage from GS24-29 - all crops have tillered well this year. Brown rust pustules still very evident in many crops even after frosts.
Eastern Counties: Most crops have at least 2 to 3/4 tillers. Most forwards are up to 7 or 8 tillers and just below wellington boot height. Some looking as though could lodge.
East Midlands: Crops at GS 23-24 and look well. Good control from autumn mildewicide but return of milder conditions may get it going again.
West Midlands: Some very yellow crops out there, although pre Christmas manganese + kayak crops do look better with less dead leaves in the bottom of the crop.
North East: Most crops are fully tillered and in the range GS24-27, and are well grown with good ground cover. The frosts don't seem to have affected the barleys as much as they have the wheat so they still have good colour.