Peter Griffith

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The Farming Online autumn sowing survey reveals that across the UK only two thirds of the planned area of wheat have been sown. The staggered sowing and unfavourable growing conditions has meant that only half of that sown has so far established.

The reduced area of wheat and the delayed establishment has immediate consequences for harvest 2013. Couple this with the damaged soil structure from the excessive rain this year and things don't look good for our next harvest.  Crops won't root well in these sodden soils and will be vulnerable to a series of potentially damaging future weather events. A cold winter will see more frost lift damage than usual. A dry spring will lead to higher tiller deaths and curtail plant vigour. In fact any weather pattern between now and April that restricts growth is unwanted. The chances of getting the perfect growing season from now until harvest are slim at best.

Predicting next year's harvest

We've taken the survey figures that have been submitted to us and run a 'what if' model from the results so far. We've split the results into English regions and treated Scotland as a block. Statistics from Defra, the Scottish and the Welsh Governments show that typically 92% of the UK wheat production is from England, 6% from Scotland and the remainder form Wales and Northern Ireland.

The Defra statistics for wheat area in England by region have been used as a bench mark. The figure used in the table is the average hectares of wheat per region over the 5 year period 2007-2011. We've compared this against the results submitted to us to give a percentage of the area surveyed for each region.  The 67 000 hectares in the survey represent about 4% of the UK average wheat crop. It gives a good first draft to run a model of the problem faced.

We asked two questions (1) what was the planned area of wheat and (2) what percentage of that has established. We use this figure to extrapolate to the national level. We end up with two sets of figures, the area of wheat established and the area of wheat sown but not yet up. The percentage of crop sown by region comes from figures supplied by agronomists within the AICC.

Assumptions.

The model takes the percentage of crop sown to give a regional and then national figure for wheat sown. The percentage establishment gives us an area of crop likely to yield if conditions are right. Typically earlier established crops yield from 9 - 11 t/ha. But crops this year are a month behind typical and so the yield potential has been dropped to 8 - 9 t/ha for crops already beyond two leaves. Those yet to emerge are difficult to asses but assume 100% establishment (eventually) and that the yield potential for these will be around 7 t/ha. Many will say that late sown crops can do well. However, late sown crops in structureless soils already above field capacity are unlikely to do well. There are a lot of these.

Output results

The table shows the output from the model giving a total tonnage for crops already sown at 9.7 MT somewhat short of the 13.6 MT consumed in the UK in 2011. 5.1 MT short of an average UK wheat harvest. The model shows 0.63 million hectares of planned wheat still unsown which would need to produce 8 t/ha to meet the target of an average year’s harvest. Couple this with the abysmal harvest this year and we need every grain we can get.

The take home message is to keep sowing wheat until the end of January whenever and if ever conditions allow.

Background to Data and output

Column A - the hectares in the sowing survey. Column B - the 5 year average hectares of wheat by region from Defra statistics. Column C - the percentage of the Defra figures surveyed. Column D – the average percent sown per region from surveys.

Column E – the extrapolated figure for regional hectares sown (Col D x Col B).  Column F – area of the crop established from sowing survey. Column G – the potential hectares of established crop per region (Col F x Col E).  Column H – the hectares for late emerging crops.

Column I – estimated yield of already established crops. Background data for this comes from the previous 5 years Farming Online Harvest Results yield per region.  Column J – tonnage from wheat already established. Column K – yield t/ha for late emerging crops. Column L - tonnage from late emerging wheat already sown. Column M - total tonnage from crops already sown this autummn.

Submit your own results.

To help us keep this data up to date please submit your own sowing data to the Farming Online autumn sowing survey.

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