04 April 2014: A warmer spell has pushed crops on with a yellow haze now evident in most oilseed rape crops. Winter wheat crops are moving towards GS31 and final leaf three is expected out in the next 10 -14 days making T1 timing of April 19th pretty much as usual. Mildew is curiously absent considering how prevalent it was over winter. Sclerotinia risk is increasing as soil temperatures climb, crops flower and rain showers fall.
Pollen beetle threat reduced as crops flower:
T1 fungicides planned for forward crops of wheat:
Sclerotinia - evaluate threat:
Yellow rust at low levels in most regions:
Wild oats emerging:
Brown rust in southern wheat:
Net-blotch and Rhynchosporium at low levels:
Winter Oilseed Rape
Light Leaf Spot damage photo P Cowlrick
South East: All crops now range from Early flowering (Quartz/Ovation/Vision) to flowering (Alienor/Trinity). Final N applications now mostly been completed before crops got too tall.
Pollen beetle: low levels only.
Phoma: only very low levels of renewed leaf spotting are evident in crops that were sprayed in November.
Light Leaf Spot: worst affected crops have had canopies badly affected by infection - triazole fungicides are definitely not as effective as they were against Light leaf spot and varietal resistance will become an important consideration in varietal choice for subsequent years.
Sclerotinia: with soil temperatures increasing again this week to around 9-10oC, conditions are potentially conducive to the germination of sclerotia, particularly under thick canopies.
Weed control: now too late for further herbicide treatments.
Eastern Counties: Crops now just coming into flower but the cold week slowed the process down and varieties and drilling date have made a big difference. DK Cabernet is particularly late coming into flower. Growth is up and down across fields and generally uneven this will probably lead to a long flowering period. Canopies seem open which should help light penetration.
Light Leaf Spot: still not developing.
Pollen beetle: have migrated into crops and are still migrating. Beetles not at threshold levels and crops now coming into flower. Treating late direct drilled crop which has been pigeon grazed and is very spindly.
Sclerotinia: aim to consider first sclerotinia spray about 3 weeks after previous fungicide at early flower before petals start to fall.
East Midlands: Most crops now at late yellow bud to early flower apart from the odd late drilled crop. Cool and wet weather last week means that some farms concentrating on catching up with T0 on wheat at the expense of growth regulators on rape.
Light Leaf Spot: levels remain low.
Pollen beetle: numbers have built up with high numbers on some plants but with crops flowering they are making for the flowering heads and leaving nearby yellow bud alone. None at threshold and would not expect to spray as flowers emerging.
West Midlands: Many crops now starting to flower even the more recalcitrant crops of Troy have flowers open. Final nitrogen dressings going on before crops get too high. Some will apply a final late flowering liquid N dose.
Pollen beetle: rare
Club root: two cases now both on Troy.
Light Leaf Spot: trace levels in some crops.
Sclerotinia: fungicides being planned for mid flowering early petal fall.
North East: Most crops are between yellow bud and early flowering. Sclerotinia fungicides now being planned.
Pollen beetle: higher levels in last few days approaching threshold.
Light Leaf Spot: most serious problem in rape at the moment.
Phoma: traces levels.
Yellow rust evident in crops
South East: A return to warmer weather has seen crops respond with some vigorous new growth, particularly fields where rooting has not been impeded by wet soils. September and early October sown crops of Gallant, Solstice, Crusoe and Cordiale have leaf 4 50-75% emerged on main shoots, with tip of leaf 3 just showing in some crops of Cordiale and Gallant now. Claire, Scout, Leeds and Diego are still around 10 days behind developmentally.
Brown rust: generally only low levels detectable at present, apart from some earlier sown crops of Crusoe which are carrying readily visible pustules on lower leaves (including leaf 5) - likely to be a persistent problem on any unprotected new foliage throughout the season if conditions remain favourable.
Yellow rust: only evident in fields/crops that did not have seed treatment (particularly Solstice, Gallant and Claire).
Mildew: no active pustules seen to date.
Septoria: most September/October sown crops are carrying very high levels of Septoria on older leaves.
Eyespot: symptoms becoming more prevalent.
Weed control: some surviving patches of blackgrass in a few areas that will be sprayed-off with Roundup once it is clearly visible.
Eastern Counties: Some mid September drilled wheat is at GS 31 and will require T1 fungicide in 10 -14 days. Temperatures have significantly increased this week, with highs of 17 degrees. This has started to move cereals on after the cold snap. Most T0 have or are being applied.
Yellow rust: seems to be under control.
Brown rust: trace levels.
Mildew: trace levels.
Eyespot: there is little eyespot to be found at the base of plants.
Septoria: obvious on lower leaves.
Weed control: Wild oats, Fools Parsley and Groundsel all appearing. Curiously low levels of cleavers.
East Midlands: Earlier crops at GS 31 with average crops at late GS 30 but have slowed down a bit and expect GS 32 to be about mid April for early crops and about third week for average crops. Late drilled crops at early GS 29. Soil conditions good with no problems and dry weekend allowed a lot of spraying to be done.
Yellow rust: levels remain low.
Brown rust: none seen.
Septoria: plenty on older lower leaves which are dying off now but risk is there. T0 now on almost all crops after last weeks delay due to weather.
Mildew: levels remain low even on susceptible varieties such as Claire and Solstice.
Eyespot: still not a lot about but some lower stem browning could become eyespot or could be fusarium - difficult to say at this stage. Any deemed at risk will have an eyespot spray, particularly quality wheats
Weed control: cleavers, generally not a lot to cause concern at moment.
West Midlands: The most forward crops now have final leaf three just showing, but these are the minority. Most crops are between GS 30 - 31. Field work has been held up by showery weather.
Yellow rust: treatable levels on some Solstice.
Brown rust: none seen.
Septoria: all crops crops carrying high levels. T0 applications now on.
Mildew: very little seen even on late sown Leeds.
Eyespot: stem browning become more obvious in some crops with the beginnings of eyespot lessions showing.
Weed control: More cleavers now showing. Flush of charlock over the last week or two.
North East: Forward crops now at or approaching GS 31. Majority are at GS 30. There are some lush crops about with many tillers. Ground conditions are good which has allowed growers to catch up with spraying.
Yellow rust: becoming evident but T0 fungicides now on.
Brown rust: none seen.
Mildew: none seen.
Septoria: present in many crops.
Eyespot: no obvious signs yet.
Weed control: Polygonum weeds, charlock, wild oats other spring weeds starting to emerge.
South East: Crops now generally at GS30, with the odd fertile field of Cassata now at GS31. T1 applications scheduled for Cassata, Glacier and Cassata in next 10 days and Volume a few days later. N+S been applied to all crops, with remainder being applied in two splits around end March and mid-April. Rhynchosporium levels increasing rapidly in thicker and more fertile crops of Cassata and Glacier particularly - symptoms showing on new growth.
Eastern Counties: Some are very thick up to GS 28+ and fairly consistent. Low levels of Net-blotch and Rhynchosporium.
West Midlands: GS 30 none more forward than this 30 odd % still mid tillering. Rhynchosporium and Net-blotch present at low levels. Brown rust on Volume.
East Midlands: Forward crops at GS30-31 with later crops at GS 29-30. Disease levels remain low but wetter conditions may get Net-blotch and Rhynchosporium going again. T1 to go on forward crops in 7 days or so depending on weather and growth.
North East: Crops range from GS 24 to GS 29. Some crops are lush with many tillers. Low levels of mildew, Net-blotch and Rhynchosporium. Brown rust in Cassia.