Attention to detail essential in meeting beet yield targets
SUGAR beet yield averages on the up and two consecutive record breaking years begs the question as to how high they can go. Dominic Kilburn seeks advice on raising yields further and, apparently, ‘the sky’s the limit’.
Sugar beet growers in England could be averaging more than 80 (adjusted) tonnes per hectare by 2020, if the current trend in sugar beet yield improvement continues.
These kind of yields, however, will only be realised if close attention to detail in all aspects of growing the crop is maintained, and the predicted extremes of climate changing weather are kind on the crop.
According to Robin Limb, British Sugar’s agricultural development manager, average yields of 80t/ha (32t/acre) are not unrealistic to expect, particularly as the current yield trend shows a 1.5t/ha (0.6t/acre) rise year on year.
“It will depend on who’s growing the crop in 10 years time of course, but some growers are now getting very high yields and there are no limits,” he says.
Mr Limb’s comments come against a backdrop of record-breaking yields achieved by sugar beet growers in this country. Last season’s 71.78t/ha (29.04t/acre) average was a considerable leap above the previous year’s 66.5t/ha (26.91t/acre) yield – itself a record.
“Last year we got additional summer rain at the right time and that swelled the roots and kept the crops flat out,” he says. “On the contrary, very often weather factors during the season can strip away as much as 30-40 per cent of what a crop can achieve in yield.”
There was considerable scepticism around the notion of the industry achieving average yields of 70t/ha (28t/acre) when the campaign to raise yields was launched in 2005. “We launched the 70t/ha target because we felt growers should have something to aim for says Mr Limb.
“Prices were coming down because of EU reform, and yields needed to go up to compensate.
“At the time, only 15 per cent of growers were achieving 70t/ha or more, but we made it,” adds Mr Limb, pointing out 52 per cent of growers achieved the target with last season’s crop.
Mr Limb maintains there are no physical limits on what yields can be achieved, indeed, he is expecting confirmation shortly one Norfolk grower averaged 127t/ha (51.4t/acre) last season.
“At Broom’s Barn, their best yield was as much as 140t/ha from last season’s crop and in California’s Imperial Valley - where admittedly ‘designer’ conditions exist for growing beet - they’re getting 160t/ha.
“Those are clearly special growing conditions, but it does show that yields of this magnitude can be achieved with sugar beet crops,” he adds.
Mr Limb believes, generally, it does not cost much more to get yield increases, it’s more about growers adopting what is best practice and maintaining attention to detail.
“When we see good yielding crops it’s not just because they are on good soils, although that helps, but in my opinion soil management plays a key part.”
Cultivations in sugar beet was a major area of focus for growers in the 1980s, he says but are probably less so now as a new generation of farmers begins to take the reins.
“Perhaps some growers aren’t so aware of the impact that improved soil management could have on their crop, the need for a firm and fine tilth at the top and no compaction below, for example. For those with big yields, we know soil management is key.”
Beyond this, factors such as the continuing improvement in variety breeding has assisted in better yields year on year, while Xbeet seed treatments (now applied to more than 95 per cent of the UK crop) are helping to raise germination thresholds to an average of over 90,000 plants per hectare (36,000/acre).
“Fungicides are giving growers the ability to promote late season growth and while we are cautious not to be advocating a two-spray programme for the earlier lifted crops, we know that any crops scheduled to come out of the ground from late October onwards will benefit from a two-spray programme.”
In future, Mr Limb says the supply of rainwater and irrigation will be the determining factor for beet yields in this country. “The crop has a reliance on rain and, although climate change could mean more warmer, wetter summers, which would suit the crop, we just don’t know what’s to come.”
Case Study: Patrick Claybon, HG Bliss Farms, Norfolk
Patrick Claybon who grows sugar beet out of HG Bliss Farms, situated between Wisbech and Downham Market in Norfolk, has just achieved his highest average yields ever of 102 adjusted tonnes per hectare (41t/acre).
He concedes that his mineral silt skirt soils are very good for growing beet but technological advances, in addition to attention to detail, have made the difference in recent years, he says.
Five years ago, when his yields averaged 72t/ha (29t/acre), Mr Claybon reckoned his yields had peaked, and raising them further would be unlikely. Now, with a five-year average of 86t/ha (35t/acre), he says that, potentially, the ‘sky’s the limit’.
“There’s no doubt technology is helping us raise the bar - every couple of years we seem to get new varieties that push up the yields,” he says.
Seed treatments are keeping the crop virus-free and Xbeet is improving germination, he says.
“Ten years ago for example we would question the need for a fungicide spray and usually waited until the last minute to decide if we should apply one, but now it’s almost a matter of course.
Mr Claybon explains that, ahead of drilling, all fields planned for beet on the farm are subsoiled following wheat, which is removed early in the autumn.
Land is then ploughed by the end of September with the addition of a blended ‘salt mix’ fertiliser, before being left to over winter.
With relatively high soil pH levels, he says any lime application is unnecessary on his land. A week prior to drilling in spring, fields are sprayed off with glyphosate before two passes with a Germinator cultivator leaves the seedbed ready for the drill.
“I’m not convinced I am doing anything so different from before, and I know we are getting so much help from the technology. But I would say that testing for compaction and the preparation of a good seedbed can make the difference in yield.
“We basically treat every acre as best we can,” says Mr Claybon.
The experts view - sugar beet consultant Philip Draycott
THE most crucial thing for achieving better sugar beet yields is getting the soil pH level correct, says independent sugar beet consultant Philip Draycott, who believes that planning for a crop should begin up to two years ahead of drilling.
Because sugar beet is so sensitive to pH levels, treatment with lime should begin on fields earmarked to grow beet two years ahead to provide plenty of time for the lime to be mixed in properly.
“The pH levels need testing and brought up to 6.6-7 using lime that is ploughed in during the autumn following cereals,” he says. “The following autumn, the same fields need re-testing and more lime added if necessary.
“However, if all the lime is added in the autumn prior to drilling beet, then it won’t mix in the soil in time.”
Dr Draycott maintains adequate pH levels in soil is without doubt the biggest factor in raising beet yields today, and those growers with large yields already realise this. “The trouble is many farmers don’t know where their beet crop is going to be growing two years out from drilling,” he says.
Likewise, he says organic manures are also important in raising yields and good for the rotation in general. These should be applied in the autumn, winter or spring before drilling, according to permissible levels and timings where NVZ regulations apply.
For cultivations ahead of beet planting in spring 2011, Dr Draycott reminds growers that each field should have soil profile test digs to identify any compaction in order to get soil structures in good physical shape.
“Those on the best silts and organic soils with good rooting depth don’t have to worry so much, but for the rest it’s imperative to avoid hard layers in the soil down to two metres.”
Some fields will need subsoiling, he points out but the use of a mouldboard plough as a primary cultivation pass at the end of September on the heavier land is ideal as turning over the soil reduces its bulk density. For those on sandy loam, ploughing should take place just prior to drilling.