How two farmers use regenerative agriculture to protect water

Pressure to reverse excessive nitrate leaching in both the Wessex Water well and larger Poole Harbor drainage areas has led Dorset farmer John Hawkins to radically transform his farm over the past three years.

The well is providing up to 8 million liters of water a day, but it can be out of service for three to six months of the year due to too much nitrogen, explains Tim Stephens, a Wessex Water drainage advisor, to Mr. Hawkins during the transition.

A total of around 2,000 tons of nitrogen from 400-500 farms plus sewage treatment plants from Wessex Water reach the Poole Harbor catchment area every year.

See also: How technology helps farmers adopt regenerative agriculture

“Natural England and the Environment Agency” [EA] believe that this has to drop to around 1,200 t in order for the nutrient supply to be reversed. “

This results in a target of 18.3 kg / ha / year nitrogen for all agricultural land uses.

Voluntary approach

But instead of designating the catchment area as a water protection zone, which would have led to considerable restrictions, a voluntary approach was started.

“Farmers in this part of Dorset use a tool to calculate their nitrogen leaching and are then set targets to reduce it.”

Basic economics played a role in Mr. Hawkins’ decision to rise to this challenge.

A comparison of his usual rotation over five years with the involvement of 90% of the 240 hectare farm in a mid tier countryside stewardship program showed that it was more profitable not to grow rapeseed and wheat on his hilly chalk lowlands.

“Getting a guaranteed income is nice,” says Hawkins. “The margin was better than what I got and I can predict what I’ll get next year.”

Options to reduce nitrate leaching

• Include parts of the farm with the worst N use efficiency in landscaping programs
• Consider perennial plants such as B. canary grass – no entry + roots in the ground all year round
• Add more spring harvests to the crop rotation – lower N requirements and the ability to grow catch crops beforehand
• Avoid bare soils whenever possible to create soil carbon and create a buffer to slow the flow of water through the landscape
• Reduce the nitrogen intake due to the improved N-Cycling

As a result, half of the 90% of the farm was placed on a two-year grass legume fallow (AB15) made of red clover, vetch, grass and clover in January 2018.

This remains as a catch crop before it is sprayed and drilled directly into a low-input summer malting barley (AB14).

A cover crop is brought into the standing spring barley by a fertilizer spinner, before another grain with little use is used.

The other half of the farm begins with the cultivation of catch crops and the low-use summer cereal part of the crop rotation before the legume fallow is converted.

Deliver good

“I deliver all the good things you hear about – biodiversity, carbon sequestration, nitrogen reduction, while cutting my costs.”

In addition to mid-tier payments, he is receiving funds from Wessex Water for field reversal, used government capital grant programs to fund the purchase of a Simtech T-Sem direct drill, and has also recently participated in an emissions allowance program as his base payments scheme.

The changes have resulted in a drastic reduction in its nitrogen leaching, reducing it to just 12-15 kg / ha / year nitrogen via the rotation, below the EA target.

By comparison, his previous winter-dominated crop rotation would have been over 50kg / ha / year at N, while in 2015 it was around mid-30s with 50% winter crops and 50% spring crops with some catch crops, Stephens suggests.

“It could mean that in the future, Mr. Hawkins may sell nitrogen credits to others who cannot achieve the goal,” he concludes.

Diversity is key to reducing the threat of soil erosion in Herefordshireshire

Ben Taylor-Davies

If Mr. Hawkins combats leaching by simplifying his system, Ben Taylor-Davies will protect the water from phosphate pollution by using as much diversity as possible in his system.

Soil erosion from a field surrounded by a 6 m long border next to a hedge planted in 1974 opened the eyes of the Herefordshire farmer and regenerative agriculture adviser to the problems on his farm.

“It was the frightening realization that as you continue to cultivate, you don’t realize what you are losing.”

It farms approximately 230 acres of highly erodible, mostly loamy sand in the River Wye catchment, and not only is erosion depleting an important asset, it is also contributing to phosphate pollution in the Wye catchment area.

“We are losing around 1.2 tonnes of phosphate per day across the catchment area, which costs around £ 175,000 / year. It’s scary.

“So I decided to fish for this bottom and these nutrients.”

To do this, he focuses on his river bottom and grows large biomass catch crops that hold the soil that comes down the river, he says.

An important crop for the farm is potatoes, which along with a few other vegetables, he says, are the most susceptible to erosion. “But if we’re to still eat our five a day, someone has to find sensible solutions to produce them.”

“Biological Flood”

His goal with potatoes is to remove insecticides, herbicides, phosphate, two-thirds of its nitrogen, 50% of its irrigation, and half of its plant rot sprays. “I use a technique through rotation that I call ‘biological tide’.”

For a long time he assumed that the problems with potato cyst nematodes were worst in the river floor because they came in floods, he explains.

“But of course our plants died there, there was no living root and very little biology.

What comes into play with very little biology is our pests, so we created massive problems with the fact that we had no live roots in much of our soil for a long time.

He uses the “biological flood” to feed the soil with living roots for as long as possible.

Catch crops are grown before the potatoes, which are grazed by sheep in winter and shortly before the potatoes are grown.

The potatoes are planted with a companion crop of peas, vetch and buckwheat directly into the catch crop residues in a single-pass system.

Wildflower strips

Areas prone to erosion have extra-wide buffer zones, while the headlands are planted with wildflowers. He also plants strips of wildflowers in the field to support beneficial insects.

“Ironically, the very same device that deposited nematicides when planting is now destroying soil life.

“The companions fix nitrogen for the harvest, supply flowers for beneficial insects and also acidify the root zone to protect against scab and mobilize phosphate. So there are several reasons to plant them. “

He also uses a microbiological inoculant made from his Johnson Su compost and fish hydrolyzate on the farm to further boost microbial activity in the soil.

Putrefaction is first treated with the help of a diet informed by juice analysis. Last year he only needed three injections of fungicide.

“We’re not free from rot, but you can certainly control how much rot goes into the crop through diet.”

Better nutrition

Better nutrition also helps reduce the plant’s breathing and reduce the need for watering early in the season, he says. But as soon as watering or rain increases the pressure of putrefaction, he uses fungicides every 10-14 days.

“You can’t lose your harvest, but I think there is a lot more to learn how to interpret nutritional data for tuber rot printing.”

Last season was the first year this system was tested and he says he saw no impact on yields.

Similar efforts to maximize biological activity and diversity are happening across the rest of the rotation and across the company, he says.

Various livestock farms, from sheep to cattle to alpacas, are integrated into the agricultural successes as far as possible in order to generate more income with the same area.

“The more diverse you can be, the more diverse your income streams, the more positive your business will be,” he concludes.