Diversity is one of the five pillars of regenerative agriculture and for the Lockerley Estate in Hampshire, tripling the size of its rotation has led to both environmental and financial gains.
Since 2015, the 1,100-hectare estate’s rotation has gone from a typical winter wheat, oilseed rape, spring barley rotation to growing nine different crops which include peas, miscanthus and beans.
Farm manager Craig Livingstone told the Oxford Real Farming conference that the estate concentrated on marginal gains and although it had had a systems shake-up in the past five years, much of its machinery infrastructure remained the same.
The predominantly arable enterprise now grows 200ha of cover crops, has introduced livestock through working with local cattle and sheep graziers, grows in-field pollinator strips, utilises different types of organic manures and grows niche crops including poppies for morphine.
Mr Livingstone said: “The wide rotation allows us to integrate compost, muck and cover crops; means we can be far more accurate; and for our technique and timing to be better. It also allows us to produce crops people want that are slightly more niche.”
However, one of the key benefits has been a reduction in fertiliser use, he said.
“It has allowed us to reduce our fertiliser tonnes by over 30 per cent in five years and spend on pesticides has reduced by 40 per cent.”
An array of different cover crops not only create forage for sheep, but capture on average £170-worth of NPK per hectare and spring barley nitrogen requirements have fallen by 28 per cent, following a cover crop.
However, bagged fertiliser remains a significant hurdle in the farm’s ambition to reach sub-zero carbon, Mr Livingstone said.
Using Farm Carbon Calculator, in 2019 the farm emitted 561t of CO2. In 2020 it fell to 388t CO2.
“Next year having dropped OSR, significantly increased our pulses and a few other things, I anticipate [the farm’s carbon footprint] will be about 150t CO2. By 2022 into 2023 the estate will be net zero. But that does not mean we have won because we need to be sub-zero. Our biggest offenders are blue [fertiliser] bags and red diesel. We are working really hard to identify how to correct this."
Meanwhile, conference growers were warned of the dire consequences of abandoning rotations.
Working for international aid agencies for 45 years, Tom Morrison, said he saw first-hand what can happen when soils become severely degraded.
In the 1990s, North Korea, which Mr Morrison visited many times, experienced a famine which killed three million people out of a population of 21m. Rice yields went from eight tonnes/hectare to 3t/ha, he said.
“There was a massive fall in natural soil fertility – the soil died, it physically collapsed. North Korea had abandoned crop rotations and including animals, relying on chemical arable farming.”
He led a team for the International Fund for Agricultural Development (IFAD).
“We proposed to IFAD a four-course rotation which led to the introduction of more ruminant livestock as a condition of aid.”
This was accepted by IFAD and adopted by North Korea’s Ministry of Agriculture as official policy at national level, said Mr Morrison.
“In 2019, a good year, weather-wise, national average rice yield was just over 6t/ha. It is still not up to the 8t/ha of 25 years ago but getting there. In 2018, a bad year, weather-wise they were 4.4t/ha – soil resilience is still far from restored,” he added.