14 March 2014: A drier week has helped catchup on field work. Warm sunshine in the afternoons has spurred crops on too. Oilseed rape crops are now rapidly moving towards yellow bud stage with some individual plants in the south starting to flower. Light leaf spot still remains the main disease to watch. Pollen beetle are mainly restricted to the eastern and southern counties but nowhere are they reported as being at threshold levels yet. Winter wheat crops are picking up, responding to lengthening days, warmer temperatures and nitrogen applications. Yellow rust is evident in many crops and T0 fungicides are timed for end of next week. Brown rust is evident in winter barley crops of Volume.
Light leaf spot at high levels in South:
Pollen beetle threat as temperatures rise:
T0 fungicides planned for forward crops of wheat:
Yellow rust at low levels in most regions:
Brown rust in wheat in South:
Net-blotch and Rhynchosporium at low levels:
Pollen Beetle action thresholds: Migration into crops starts when temperatures reach 12 - 15 0C
- <30 plants/m2 ~ 25 pollen beetles/plant
- 30-50 plants/m2 ~ 18 pollen beetles/plant
- 50-70 plants/m2 ~ 11 pollen beetles/plant
- >70 plants/m2 ~ 7 pollen beetles/plant
Winter Oilseed Rape
Watch out for pollen beetle as temperatures rise.
South East: All crops are now extending and range from stem extension (Quartz) to Green bud (Alienor/Trinity) ? many have retained a significant canopy this year, with GAI of >2 being common. Similar early extension and canopy structure in many crops to 2012, raising lodging concerns.
Pollen Beetle: there are some about.
Phoma: only very low levels of renewed leaf spotting are evident in crops that were sprayed in November.
Light Leaf Spot: some crops/varieties are only carrying low levels (10-20%) of infection, particularly Trinity, Expower and Ovation, while some other crops are carrying severe levels of infection (60-80% of plants) particularly Alienor, Quartz and Charger.
Weed control: most herbicide was eventually applied between December and end of January but a few fields were missed out as just too wet.
Eastern Counties: There is a great variability in growth from field to field. Some fields are well into stem extension with buds proud above crop and almost at yellow bud stage while others are in the very early stages of stem extension with the buds barely above the canopy. Residual nitrogen seems to have fuelled the growth on light soils, e.g. turkey muck applications, inherently fertile sites and those fields which have been ploughed are the most forward. Some crops have run into early stem extension with small canopies ? I have never seen the crop move into and through stem extension so quickly. Within fields there is a great unevenness of growth as well.
Light Leaf Spot: a little appearing - not developing a great deal in the current dry conditions.
Pollen Beetle: scarce due to recent light frosts, but be vigilant.
East Midlands: Forward crops at green bud or advanced green bud with most crops at green bud showing stage. Almost all crops have a Green Area Index of one or above (a few with two) and will require a growth regulator. First Nitrogen now on, split where forward, delayed (and reduced) where very forward and average crops have had about half total dose mainly to fit in with sulphur requirements and fertiliser blend.
Light Leaf Spot: levels remain low and with vigorous growth now do not look a problem.
Pollen Beetle: none seen yet.
Weed control: it is now too late in many crops for further broad-leaved weed control.
West Midlands: Green buds extending on most crops, Avatar, PRW21 and Cubic are the most forward. Some crops at yellow bud. Crops are showing some very uneven growth both within and between fields. Most will have applied fertiliser by the end of this week.
Pollen Beetle: still none seen but day time temperatures have been below 15C.
Club Root: two cases now, both on Troy.
Light Leaf Spot: trace levels in some crops.
Weed control: Charlock and Runch are the main issue and unfortunately it is now too late in most crops for control.
North East: Crops range from stem extension to green bud. Fast growth. Wide temperature fluctuations, with frosts in morning and warm midday temperatures.
Pollen Beetle: none seen.
Light Leaf Spot: increasing levels of light leaf spot seen.
Weed control: herbicides worked well in warm winter.
Yellow rust evident in crops.
South East: Wheats now responding to applied fertiliser and generally are starting to recover within seven days of waterlogged yellowing effects. Growth stages are generally late tillering to early stem extension, with the most advanced fields approaching true GS30 ? primarily Gallant and Cordiale. Some lower lying and heavier fields remain very wet and soft in places preventing any fieldwork, though these are very much the minority now. In general it is remarkable how well many fields have taken the excessive winter rains.
Brown Rust: generally only low levels detectable at present but likely to increase rapidly with current daytime temperatures hitting 15-17ºC.
Yellow Rust: generally most at risk varieties were treated with seed dressing, which has prevented any yellow rust in most crops ? only evident in fields/crops that did not have an effective seed treatment (particularly Solstice, Gallant and Claire).
Mildew: no active pustules seen to date, though may well develop quickly as crops respond to applied nitrogen and canopies thicken up.
Septoria: most September/October sown crops are carrying very high levels of Septoria on older leaves.
Eyespot: stem based browning symptoms can be readily found in many crops.
Weed control: later sown crops that did not receive any autumn herbicides are now a priority. Bromes are more obvious on headlands.
Eastern Counties: The majority of crops are at GS 28 to 30 but there are some wheats after sugar beet or maize which are only at the 3-4 leaf stage. Fields are drying out with plenty of available moisture.
Brown Rust: trace levels.
Yellow Rust: trace levels seen in many varieties, not just the low rated ones. Treatable levels in some backward crops.
Mildew: trace levels.
Septoria: obvious on lower leaves.
Eyespot: beginning to become more apparent.
Weed control: Wild Oats, Fool's Parsley and Groundsel all appearing.
East Midlands: A few forward crops at GS 30 but these will stand still now for a bit until days lengthen. Most crops at GS 25-29 with later crops at GS 23-25. Fields drying well and most accessible for fieldwork although one or two wet spots causing wheelings. Many crops have now had first nitrogen either alone or with sulphur. Manganese deficiency continues to show up particularly as fields dry out and crops have had wet feet.
Brown Rust: none seen.
Yellow Rust: levels continue to remain low and hopefully will allow crops to get another 10 days or so before T0.
Mildew: levels continue to remain low and cold nights helping to hold it back.
Septoria: remains on older leaves and will be a threat.
Eyespot: odd stems showing Sharp Eyespot but not a lot of lower stem based browning yet. Continued dry weather will help, although night fogs are making lower stems wet.
Weed control: any outstanding blackgrass sprays now on and continue to find odd plants in fields where sprayed indicating possible resistance. No major emergence of broad leaved weeds yet.
West Midlands: Wheat sown early September is at GS30, some main stems nearly GS31 (Grafton and Solstice). Vast majority of the remaining crops which were sown from mid/end of the following week are still at the mid tillering stage. Crops sown end of November/early December are still only at the 3-4 leaf stage/one tiller (mainly where seed from 2012 was used, which was not fit for purpose then and most certainly was not of any use at this late stage of the season in 2013). Field conditions have dramatically improved on 14 days ago, with light land farms beavering away with fertiliser applications last week, and pretty much all the rest joining in this week. Still some very wet patches in most fields, which are being avoided for now.
Brown Rust: none seen.
Yellow Rust: treatable levels on early October sown Oakley, early sown Solstice and Viscount still clean.
Mildew: recent frosts keeping this under control.
Septoria: early sown crops carrying high levels.
Weed control: bromes are well tillered in early sown wheat crops, more manageable in crops sown in late September onwards, ploughed drill fields are clean.
North East: Most crops range between GS 23-25 but forward crops are beginning to extend. There are some lush crops with many tillers in some instances.
Brown Rust: found in Target.
Yellow Rust: seen in Leeds, Santiago and Kielder.
Mildew: levels have declined.
Septoria: present in many crops.
Wheat Bulb Fly: dead-hearts in some crops.
Weed control: Cleavers and Knotgrass beginning to emerge.
South East: Crops now generally at GS 24-30. Fertiliser been applied to all crops, with remainder being applied in two splits around end March and mid-April. Rhynchosporium levels increasing rapidly on older leaves in crops of Cassata and Glacier particularly. Brown rust in Volume.
Eastern Counties: Some are very thick up to GS 28+ and fairly consistent.
West Midlands: Crops recovering from the wet conditions and most are at end of tillering. Rhynchosporium and Net-blotch present at low levels. Brown rust on Volume.
East Midlands: Forward crops at GS 26-29 but generally at 24-26. Rhynchosporium and Net-blotch present at low levels.
North East: Crops range from GS 24 - 29. Some crops are lush with many tillers. Low levels of mildew, Net-blotch and brown rust.