: Mild conditions continue to favour rapid growth in emerged crops. Oilseed rape crops in complete contrast to last autumn have established well and attention is turning to the need or not to apply growth regulators to forward crops. Phoma levels have not progressed over the last week and nowhere are crops at threshold levels for control. Winter cereal sowing is well advanced this year with many farms having completed wheat and barley sowings, with the exception of those following maize or late lifted crops of potatoes or beet. The mild conditions, though good for sowing, have also increased the risk of BYDV this autumn especially in untreated crops. Temperatures will need to drop below 5ºC to reduce the risk.
: 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)
Winter Oilseed Rape
Large crops may need autumn PGR (photo courtesy of Farming Online).
South East: Crops now range from 2 true leaf to 6-8 true leaves - around half of crops are now around 4-5+ true leaves.
Phoma: Rothamsted Phoma prediction is suggesting first Phoma spots should become visible from around 10th-15th October here in the South. Although none seen yet.
Slugs: good seedbeds and dry soils have minimised problems to date this autumn in most cases.
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, particularly after spring barley, indicating low dormancy in shed seed.
Eastern Counties: In general most rape crops look well, but later sown crops still need checking for new flea beetle damage.
Phoma: first few spots of disease seen this week but levels are very low.
Flea beetle: activity more noticeable on earlier drilled crops, however large plants are growing away from the damage.
Slugs: activity continues to be low and most crops have established with very little thinning.
Leaf miner: blistering seen but at low levels.
Weed control: graminicide applications have worked well on cereal volunteers.
East Midlands: Generally all crops look well with a few very forward which will need holding back. Most crops at 3-5 leaves with only the very late drilled one at 1-2 leaves. Some crops will require growth regulator soon as growth is rapid.
Phoma: still notable by its absence even in very forward crops - continued dry weather may well hold it back.
Slugs: very little damage seen and most crops now beyond stage where any damage can be done.
Weed control: blackgrass continues to emerge and graminicides are now going on when weather permits.
West Midlands: Crops range from 3-9 true leaves. Some very forward crops about.
Slugs: some patches of crop loss on particularly heavy ground and on min tilled lighter land. Need monitoring carefully.
Leaf miner: in some crops but not at damaging levels.
Phoma: first signs but still at very low levels.
Weed control: as with the cereals there has been some obvious herbicide uptake by crops this year. Follow up graminicides for second flush of bromes and volunteer cereals going on next week.
North East: Crops continue to grow well and range from 1 to 5 true leaves. Symptoms of moisture stress on cotyledons in dry areas. Average temperature for the week: 15 degrees, Rain 2.6mm for the week.
Slugs: a little activity.
Phoma: none seen.
Weed control: more cranesbill and black-grass emerging this week.
Early sown wheat emerging well (photo courtesy Farming Online).
South East: Drilling of first and second wheats now mostly completed - only fields left to drill are after maize/vegetables. With ongoing warm and moist soils, crops are still emerging around 10 days after sowing - earliest sown crops (20th Sept) now at 3 leaf stage.
Slugs: activity has increased notably this week in crops after oilseed rape, following around 6-10 mm of rain at end of last week and some dewy/misty mornings.
Weed control: blackgrass can be readily found emerging with wheat in problem fields, despite having killed several seedbed flushes with Roundup.
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 ranges 1-3 leaves and in very forwards crops it has the beginnings of a tiller.
East Midlands: Forward crops at 2-3 leaves, some just emerging and later ones just chitting. Emergence is generally quick. All crops that are through have established well. Generally dry soils on top and some excellent seedbeds but some of the cloddier soils needing some rain to penetrate. However, many soils are good with moisture just below but at 15cm heavier soils are very much like plasticine.
Slugs: very low levels seen in emerging crops with no pellets required so far.
Weed control: blackgrass emerging quickly and windy weather delaying pre emergents may be a problem if it persists. Generally many pre emergents have gone on within a day or two of drilling but some rain would be useful or we will have a repeat of 2012 when it was too dry.
West Midlands: Crops range from emerging to first tiller. Crops still coming up in just under 10 days, only 1st wheats left to drill now is after maize, potatoes and fodder beet, with a big chunk of the 2nd wheats also now in. The recent rain combined with mild conditions has resulted in some pretty rapid uptake of herbicides in treated crops. They are now showing quite marked bleaching. BYDV control will be important this year.
Slugs: Still not a major issue, isolated patches in most crops.
Aphids: can be found.
Mildew: on light land with 3 true leaves has low levels of mildew.
Weed control: flush of weed seedlings coming through where no pre-ems applied. Worse crop scorching/bleaching from herbicides for some years, testament to how quickly these crops are growing!
North East: It's been another busy week for sowing with a lot of crops now in the ground. Crops range from just emerging through to two leaf stage.
Slugs: no problems so far.
Weed control: cleavers beginning to emerge.
South East: Winter barley drilling now mostly completed. Main varieties are Volume, KWS Cassia, Glacier and Cassata.
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. Approximately 90% drilled. Mildew appearing on early sown crops.
East Midlands: A few crops just emerging.
North East: Most crops now sown. Earliest sown now at 2 leaf stage. Main varieties are Cassia, Volume, Bamboo.