Arable Scotland round-up – Farmers Guardian

There are far fewer bare fields over winter in Scotland now as the popularity of cover crops grows, said Hutchinsons’ arable agronomist Morven Anderson.

Farmers considering cover crops should plant whatever suits their system best, she said, adding that Scottish conditions meant drilling times, soil temperatures and frosts could sometimes provide a challenge for some options.

She said the firm’s Maxi Cover and Maxi N mixes had worked well on its Fife Helix farm trial site. Autumn trials looked at establishing the mixes versus fallow ground and tissue and soil samples were analysed before cover crop destruction.

“Both cover crop mixes contained a good source of sulphur and micronutrition and the ground underlying had an extra 25kg of nitrogen relative to the fallow.

“This successfully demonstrated a measurable benefit of the cover crops’ use-retaining N left over from the previous crop,” said Ms Anderson. With the prevalence of brassica and veg crops in the East of Scotland, she said the firm had recently launched a MaxiVeg cover crop blend which has no brassicas or veg in the mix.

Carbon mapping the field where Arable Scotland was held – at the James Hutton Institute’s Balruddery Farm, on the outskirts of Dundee – produced some interesting results.

According to Hutchinsons head of field-based IT, Lewis McKerrow, the area of the field with the lightest soil had the highest organic carbon figure.

In most cases, heavier soils would be expected to hold the most but these areas had 50-60 tonnes/hectare of organic carbon compared with 90-100t/ha in the lightest area of the field.

The lighter area was also found to have an organic matter of 8-10 per cent, compared with an average of 4 per cent in the rest of the field.

Results from the firm’s TerraMap Premium soil mapping, done with a Suzuki Jimny, showed that active carbon – the amount which is feeding the soil and microbes – was much more even across the field. “The result was a surprise and raises some questions,” Mr McKerrow said.

“It does show that if you can get the organic matter right in sandy soil, it can have the right conditions to sequester carbon.”

The area of light soil has been in grass for a long time as it is routinely used as car parking for events at the farm, whereas the rest of the field is in an arable rotation.