Sugar Beet Soils
When Hutchinsons agronomist, Simon Wilcox took over the tenancy of Warboys Farm two years ago, he inherited soils that had been relentlessly ploughed and an imploding blackgrass problem. As an agronomist and also a farmer, Simon knew that he needed to address these issues head on and adopt both short and long-term strategies to improve soil health and lower the weed burden.
Inspecting soil structure is key to deciding on the most appropriate cultivation and cropping strategy for individual fields, says Hutchinsons soil health expert Dick Neale. lt's a great opportunity to Identify the presence, extent and depth of any compaction, but also to evaluate other aspects like slug pressure for the following crop and general soil health.
"Simple things like looking at the number of worms, texture and smell of the soil can tell you a lot about what's going on beneath the surface," he says.
Simon had very little historical farm data so opted for a full 'healthy soils' assessment to give him more insight into the state of the ground he was farming.
Hutchinsons Healthy Soils is a complete service that benchmarks and measures soil conditions in any particular field or farm, which then makes it possible to make decisions about management practices, and most importantly also allows the farmer to monitor and measure how particular changes are having an impact
Part of the healthy soils approach is to visually assess soil cores of up to 1m in depth, which shows up any zones of compaction. An infiltration test is used to further identify structural issues and an assessment is made of the soil’s texture and its cation exchange capacity.
The number of earthworms active within the top 200mm, a good indicator of soil health, is also recorded. The chemical health of the soil is taken into account, with measurements made of organic matter content, pH analysis at three depths - surface, 150mm and 300mm - as well as a full assessment of macro and micro nutrients.
"Generally, the soil was in fairly good condition at the surface, but there was a compacted layer at about 65-67.5cm depth, which had most likely developed as a result of heavy harvesting equipment" believes Dick.
"There was nothing that we could do to address this mechanically at this depth but non-mechanical methods, such as cover cropping, traffic management and improvements to organic matter placement to encourage earthworms, were areas we could work on to help improve long-term structure, drainage and water-holding capacity," he comments.
"The first step was to drop ploughing across the rotation and reduce the depth of cultivations, so that they're just moving the top couple of inches of soil," he says.
"For the cereals and oilseed rape this was relatively straight forward. But sugar beet is a different matter, with good establishment key and a crop that particularly sensitive to soil cultivations. Getting good seed to soil contact in the planting zone is essential," he says.
The decision was made to strip-till the sugar beet which would provide this, while also leaving a significant area uncultivated so that grass and broadleaf weeds weren’t disturbed.
"We recognised the challenges to taking this approach on Simon's heavier soils, but to address the soil health issues we had no choice," notes Dick.
"The first year we strip-tilled the beet in the spring using a Cousins MicroWing. We used a seed rate of 125,000 seeds/ha, aiming for a plant population of 100,000 plants/ha, and we were pleased with the results," says Simon.
Last year there was a much wetter period in early spring and because Simon doesn't have his own equipment, he didn't have flexibility as far as timing of drilling was concerned. As a result, the sugar beet was drilled into less than ideal conditions, resulting in some smearing and micro-compaction, with beet seed left sitting in cracks in places.
"Establishment was gappy and the crop didn't really perform as well as I would have hoped," he comments.
After two very different sugar beet planting seasons and mixed results, what does Simon intend to do next? "l know I can’t go back to ploughing for at least five years if I'm to gain any benefits from dropping the plough from our cultivations, so this year we've tweaked our approach. We strip-tilled the soils in the autumn and have left them to overwinter, then once conditions are favourable in the spring, we'll strip-till again just to freshen up the strips. I've also made sure I have the flexibility with equipment to allow me to do this.
"In this way, we're keeping to the core principles of minimal soil disturbance and encouraging worms, but also ensuring that conditions are right at drilling. i hope to make some savings on herbicides as weeds only germinate in the cultivated strip, and in the long run the change in practice should significantly reduce the overall weed burden."