Power grazing aims to increase soil fertility and organic matter (OM) in soils, according to Tim May, a UK-based arable farmer.
May farms 1,000ha in Hampshire, England, and sows crops such as barley and wheat. He also runs a herd of cattle and a flock of sheep.
“It’s a typical lowland farm that ran into difficulty a few years ago,” May said. He believes that arable farming has become chemically dependent, with more money spent every year on trying to maintain the yields of yesteryear.
May added: “All of this chemical use has depleted the soil.”
Chemicals that May frequently used on his farm included: fertilisers; pesticides; and herbicides.
Why is the soil failing?
A certain amount of May’s wheat crop failed in 2004. The British farmer dug a test pit in one of his poor-performing fields and had a soil expert examine the different horizons.
The soil on May’s farm was losing OM (organic matter), according to soil expert Mike Harrington.
“The soil was not getting enough time to recover. Constant cultivation meant that OM was being continuously exposed and broken up,” Harrington said.
The subsoil was moving closer and closer to the soil surface.
Introducing Power grazing
May decided to adopt the power grazing method of farming in 2013.
“I knew I had to reintroduce grazing animals onto the farm like in days gone by. This was done to recuperate the soil,” May said.
A four-year block of pasture is followed by a four-year block of crops. According to May, the crops will benefit from the pasture as it will introduce nutrients into the system.
Beef animals and sheep were brought in to graze. May measures grass regularly and believes this is vital to the success of his system.
“If we can get the animal to graze whatever leaf is left, while threading the fibrous material into the ground, we can build carbon from the top and that’s how we improve the soil quicker,” the farmer added.
When the plants flower, it creates a habitat for wildlife to flourish too which is important, May stressed.
Earthworms are key
Earthworms are central to degrading the fibrous material into OM, aerating the soil and mixing the nutrients between horizons.
There was a four-fold increase in the amount of earthworms counted on May’s land from 2013 to 2016, and May labelled these “the hidden heroes”.
Three years later, there was a massive improvement in the layer of OM present in the topsoil. Roots were 1.5m deep and earthworms were “plentiful”.
We can get a good crop off poor soils but we won’t be able to do this forever.
“Instead of being an applicator of chemicals, I’m a nurturer of a natural system; it’s much more rewarding,” May concluded.