Holistic view on slurry – From storage to field with Wolfhall Farm

This year’s exceptionally wet spring created significant challenges for farms to manage slurry storage and effective utilisation. A prolonged housing period and adverse weather conditions only added to the strains on farming operations. However, at Wolfhall Farm in Wiltshire, an upgraded slurry system allowed them to sidestep these issues and concentrate on maximising the benefits of slurry for their milking platform.

Tom Blanchard oversees the farm and looks after the arable operations, youngstock and beef. Farm manager Antony Mitchell is responsible for the dairy team, which consists of six staff members, including himself.

As well as arable and beef, the farm’s 160 ha grazing platform is made up of rye-grass and clover leys, some, including plantain and chicory, maize and fodder beet are grown on the platform as part of the reseeding policy. Maize, lucerne and herbal leys are also grown as part of the arable rotation.

They normally produce three to four cuts of silage from rye-grass leys and four to five cuts from lucerne. All herbal leys are treated with farmyard manure due to the distance from the slurry lagoons.

Since joining our Strategic Dairy Farm programme, the team has been looking to increase farm efficiency, including better utilisation of slurry to reduce artificial nitrogen usage.

“A year ago, we were barely spreading any slurry onto our milking platform and were mainly focusing it on the arable and beef sides of the farm.

"After discussions with our steering group, we decided slurry utilisation was an area we wanted to focus on,” says Tom Blanchard.

After an Environmental Agency inspection in 2022, they decided to to reshape the non-compliant earth bank lagoon during the summer of 2023 by installing a plastic liner.

Antony said:

"This lagoon now has a capacity of about 1,400 cubic meters. We also dug a new lagoon in the centre of the farm, again with a plastic liner, providing a working capacity of 5,500 cubic metres.

"We now have a total capacity of about 11,000 cubic metres, giving us roughly eight months of storage."

The team chose to expand their capacity to future-proof the farm and provide extra storage for particularly wet winters. Significant investment in slurry infrastructure was essential, and the focus now is on maximising its benefits.

Historically, the grazing platform relied mostly on artificial fertiliser.

"Until this year, we applied very little slurry on grass, just bagged nitrogen. Most of the slurry was used on arable and maize land, more as a disposal exercise," Tom says.

"Because we didn't have a separator, the slurry was generally quite thick, which made us concerned about grazing rejection, particularly for our milking cows.

“Cost-wise, it is probably about the same to spread slurry or artificial nitrogen (including purchasing the product). However, it is better to make use of something you already have.”

The farm uses an umbilical system with a dribble bar and flow meter for spreading slurry. The increased capacity allows for more strategic spreading to make the most of optimal soil conditions rather than when storage is full.

"In previous years, we would have been more concerned about getting slurry spread during the timeframe from being an NVZ – spreading from mid-January until mid-September.

"However, having the security of plentiful storage, we can focus more on a plan to work better with the soils and that fits better with our grazing rotations," says Antony.

The changes in slurry management at Wolfhall Farm are part of a broader strategy to become more productive, increase milk production from forage and reduce reliance on artificial nitrogen.

"Making sure we've got enough forage in front of us is key," Antony explains.

“We have slightly shifted the block-calving approach to have more autumn-calving cows, which means fewer cows are milking during the dry summer, reducing the need for additional feeding.

"We need to take more soil samples to monitor P and K levels because we're concerned about building indices as more of the slurry stays on the platform."

The last round of soil samples showed no major surprises, with P and K levels at twos and threes, but ongoing monitoring is essential to maintain a balance.

As Tom and Antony continue to refine farm practices, the investment in slurry infrastructure and the strategic application of slurry are set to play a crucial role in the farm's ongoing success.

“We are still on a journey to learn more about maximising slurry efficiency, but we think we’re in a good position to learn more and trial spreading more slurry onto our milking platform,” says Tom.

• Look at the amount of slurry you’re spreading and soil test to see if you are making the most of it
• Be open to learning more and ask questions. People are always coming up with new ideas and ways of doing things, so it’s good to be a part of the discussion
• Start using slurry to see what difference it can make to your farm if you’re not already applying a lot to your milking platform

Event: Optimising slurry use at Wolfhall Farm

Join us at Wolfhall Farm on 20 November to learn more about how Tom and Antony want to start better utilising their slurry and understand how you can make the most of your slurry.