18 October 2013. Wet and mild conditions continue to favour good growth this autumn. Surprisingly slug activity still appears to be a lot lower than expected given the preponderance of them last year. Other pests seem to be keeping a low profile too with only a few isolated reports of aphids, frit fly, wireworm or leatherjackets. Disease in winter cereals is reported as low with mildew recorded mainly in the west. Phoma levels in oilseed rape have yet to pick up leading some to hope that it may only require one timely fungicide application this autumn.

• Phoma control planned
• Slugs active low but be vigilant after recent rain
• Large oilseed rape crops may need PGR
• Blackgrass emerging quickly
• BYDV - use T Sum to predict risk

BYDV T sum
‘T sum’ system of accumulated day degrees above 3ºC can be used to predict best spray timings. Temperature accumulation should be started from: six weeks after sowing for imidacloprid-treated crops date of emergence for other crops one week after application for pyrethroid-treated crops.
1 Calculate ‘T sum’ by subtracting 3ºC from the daily mean temperature and adding the result to the running total.
2. If ‘T sum’ is 170 (second generation could be starting) – consider a tank-mix insecticide if treating the crop for another purpose.
3. If ‘T sum’ is 340 (significant spread imminent)

source HGCA.

Winter Oilseed Rape 

South. Crops now range from 2 true leaf to 6-8 true leaves – around half of crops are now around 5+ true leaves. Mild conditions continue to favour rapid growth and around half of crops are likely to need a PGR fungicide before the end of October.
Phoma: none seen to date, however recent rains are likely to initiate further spore release and infection before too long. Crops with 5-6+ leaves may well escape significant canker damage due to size of leaf petioles and also what now looks to be a late infection season.
Slugs: good seedbeds and dry soils have minimised problems.
Aphids: no Myzus Persicae adults seen to date, supporting Rothamsted suction trap data.
Turnip Sawfly: low levels of larvae now being found on undersides of leaves in crops that have not had a pyrethroid applied – damage looks very similar to slug grazing.
Weed control: moderate/high levels of blackgrass emerged/emerging in some crops. Aramo (1lt/ha) been applied where required and timed to target blackgrass before tillering. Worst fields where Aramo has struggled previously, are getting Centurion Max applied when crop is at 4 leaves+ - control from earliest applications is looking very good so far (98%+). Kerb is planned to be sequenced later in November/December.

Eastern Counties. Good growth over the last two weeks has meant that all but the very latest drilled crops are now well established, the earliest drilled are covering the ground well although this does depend on seed rate and row width. We are thinking that maybe we could have used a lower seed rate on some fields. It is always a balance; canopy cover is needed to help with pigeon control and to smother weeds especially on some of our lighter soils where weeds keep emerging. Have had problems with rabbit and partridge grazing on margins and pigeons are just beginning to settle in a few areas. 50 mm plus recently with heavy rain again now – very wet. No field work anticipated all week.
Phoma: still just the odd phoma spotting seen.
Flea beetle:activity more noticeable on earlier drilled crops, however large plants are growing away from the damage.
Slugs: a few areas on later drilled / heavier fields receiving an application after the heavy rain has passed through.
Leaf miner: blistering seen but at low levels.
Weed control: most min till fields had a protracted emergence of cereal volunteers due to the dry spell. An early application of graminicide worked well, however, volunteer cereals which have emerged since this early graminicide application will require controlling soon, some are getting large. More weeds are beginning to emerge through the pre-em applications of Novall +/- Centium. In particular poppies on light fields are now being earmarked for an application of Astrokerb in 2 to 3 weeks’ time.

East Midlands. Forward crops at 6-9 leaves with most crops at 4-6 leaves and looking well with good field establishment.
Phoma: levels still extremely low but recent rain may well set it going and gearing up for phoma sprays over next 2-3 weeks depending on when phoma appears. Phoma sprays generally based around flusilazole  but some forward crops to get growth regulation
Slugs: very little damage seen and most crops now beyond stage where any damage can be done.
Weed control: blackgrass contact sprays have gone on either Aramo or Centurion Max and hoping for soil temperatures to fall for Kerb application in first week November. Generally early post ems or pre em Centium have worked well despite the dry and most crops are quite clean.

West Midlands. Crops range from 3 - 9 true leaves. Some very forward crops about. In general crops looking well and some may need an autumn PGR.
Slugs: no new damage seen..
Leaf miner: in some crops but not at damaging levels.
Phoma: still only at trace levels. Applications of either PunchC or Proline scheduled to go on when weather allows.
Weed control: follow up graminicides for second flush of bromes and volunteer cereals going on.


North East. Crops continue to grow well and range up to 6 true leaves. Average temperature for the week: 11.7 degrees, Rain 39.1 mm for the week.
Slugs: a little activity.
Phoma: still none seen.
Weed control : cleavers beginning to appear.

Click here to view the Rothamsted Phoma forecast

Winter Wheat

South. Drilling of first and second wheats mostly completed – only fields left to drill are after maize/vegetables (around 5% of total). With ongoing warm and moist soils, crops are still emerging around 10 days after sowing - earliest sown crops (20th Sept) now just starting to tiller.
Slugs: activity has increased notably this week in crops after oilseed rape, following around 30-40mm in last 7 days. Now switching to methiocarb based pellets where re-treating is required.
Weed control: recent rains have thoroughly wetted seedbeds now which is activating the pre-emergence herbicides, but where blackgrass is emerged and already at 2 leaves, planning overspraying with Atlantis in next 2 weeks. There has been a significant flush of bromes on some headlands.

Eastern Counties. The continued fine weather has allowed good progress to be made, some farms have now finished drilling. Crops range from dry seed to 3 leaves and beginnings of a tiller. The mild weather has meant that some fields have emerged within 8 days of sowing. BYDV follow up sprays may be needed this year.
Slugs: more obvious on fields following oilseed rape.
Weed control: dry conditions have hampered pre-emergence herbicide activity and consequently there have been some "escapes". Blackgrass ranges1-3lvs and in very forwards crops it has the beginnings of a tiller. All fields have had a good pre em based around flufenacet and often Avadex. Early Atlantis applications have begun.

East Midlands. Generally earlier crops at 2 leaves and later one just emerging. Establishment has been excellent this year with good stands of crops. Some 40 + mm rain in last week has made topsoils sticky and little work done but little or no standing water.
Slugs: just the odd plant being grazed but on the whole no problems.
Weed control: blackgrass emerging rapidly in large numbers despite the pre ems having gone on but the pre em effect in the dry has been poor in some cases. Atlantis/Unite to go on in some cases as soon as blackgrass at 1-3 leaves. Big flushes of broad leaved weed in some crops requiring herbicide in next two weeks if weather permits.

West Midlands. Crops range from emerging to two tiller stage. The early sown crops are very forward for the time of year. Crops still coming up in just under 10 days. BYDV control will be important this year.
Slugs: just some cloddy unrolled fields needing patching .
Aphids: can be found.
Mildew: becoming more obvious on quite a few crops of Grafton, Leeds and JB Diego..
Weed control: recent rains have helped activate pre-emergence herbicides. Bromes are more obvious this year on headlands.

North East. Crops range from just emerging through to first tiller. Many plantings done this week.
Slugs: no grazing seen so far.
Weed control: cleavers beginning to emerge. Blackgrass, bromes and ryegrass beginning to emerge.

Winter Barley.

South. Winter barley drilling now completed. Earliest sown crops now at 3 leaves.
Eastern Counties. Most crops now in but later sown crops have patchy emergence due to dry seed beds. Main varieties are Cassia and Glacier with a bit of Volume.
West Midlands. Most forward crops at 3 leaf stage. Light land crops have low levels already!!
East Midlands. Crops generally at 1-2 leaves although a few late fields still to be drilled yet.
North East. Most crops now sown. Earliest sown now at 2 leaf stage.