Overall, the crop continues to develop well with the most forward crop snow at 2-4 true leaves and progressing nicely, reports the BBRO. Final nitrogen applications should now have been applied to all emerged crops.
We continue to recommend undertaking emergence counts across fields to understand the range of percentage emergence and to help identify the reasons for this range. The aim is for 100,000 plants established on every hectare.
For crops drilled on 50cm rows, the number of plants per 20m is equivalent to the number of thousand plants per hectare. For example, 87plants per 20m is equivalent to 87,000 plants/ha.
For crops drilled on 45cm rows, the number of plants per 22.5m is equivalent to the number of thousand plants per hectare.
As predicted last week, bird grazing is occurring in some fields although forward crops will grow away from bird grazing with no problems at all. Generally birds just clip the cotyledons back, however, in looser seedbeds, where beet plants are not well anchored, their feeding action can pluck the whole plant from the ground. The rain forecast for this coming weekend should help alleviate some of this grazing pressure.
Monitor headlands for rabbit grazing which will become even more apparent as the un-grazed areas grow leaving ‘half-moon shaped grazed areas behind. Electric netting can be very effective in reducing the grazing pressure on these areas.
Weed beet patches will soon be visible, and now is the time to identify these areas and plan a strategy for control. Tractor hoeing is the most effective form of control as soon as drilled beet are big enough to withstand it and before weed beet get to the 4-6 leaf stage when these larger plants can slip around the hoe blade and survive.
From current forecasts we are anticipating an average aphid season,although recent warm weather will be conducive for their build-up on over wintered hosts. However, the BBRO glasshouses in Norwich are currently building up large numbers of virus carrying aphids for our 2015 trials work and the yellow water pan network will be in position across the four factory areas by the end of April. Weekly updates on aphid numbers (and other potential insect problems) will then follow.
Over the last 10 days good growing conditions seem to have helped to give good activity from first post emergence herbicide applications. As the crop develops its true leaves, so it is possible to use more robust herbicide mixes without too much concern of damage caused by overnight frosts.
Where grass weeds are present, consider treatment soon if other weed pressures give a break in the broadleaf spray programme. Check the label to see what interval is required between graminicide and broadleaf herbicide applications. It is not always easy to find an earlier slot in the herbicide programme but if the opportunity presents itself, grass will be more easily controlled before it starts to tiller.
Now is a good time to dig inspection pits whilst soil is still damp to identify any areas of compaction. Compaction from spring cultivations can be found at depths of 10cm or so in some fields and it is a good idea to compare headlands with the rest of the field with a view to considering different cultivation practices next year if necessary.
BBRO says it looks forward to seeing growers at the forthcoming open days where, in addition to a large array of commercial trade stands there will be a range of technical presentations on subjects including:
Fungicide programmes for 2015
Crop rooting and water uptake
Varieties for 2016
As well as the trade exhibits, it hopes to demonstrate the drone technology being used to monitor trial fields. Catering, BASIS andNRoSO points will also be available.
A reminder of the dates:
12 May Grimston, Kings Lynn
14 May Bracebridge Heath, Lincoln
19 May Salhouse, Norwich
21 May Ixworth Thorpe, Bury St Edmunds