Integrating dairy and arable is proving to be a successful strategy for promoting soil health, reducing reliance on chemical inputs and tackling grassweeds for the new AHDB Monitor Farm in Wiltshire.

Ben Jeans, who manages Chalk Pyt Farm, near Salisbury, alongside his father, Andrew, successfully incorporates the farm’s 180-cow autumn-calving dairy herd and 530ha arable unit, to create a healthy business which minimises exposure to volatile markets.

The two enterprises fit sustainably hand-in-hand. Cattle manure is applied to arable land, cutting artificial fertiliser costs, while cereal straw is used in the dairy herd for feed and bedding. Maize is also grown on farm for silage, working as an excellent break crop which widens the arable rotation.

See also: Mixed farm invests in direct drill for shift to no-till

Slurry savings

Mr Jeans explains that organic manure from his Holstein dairy herd is an excellent source of crop nutrition which significantly reduces fertiliser expenditure on the 830ha farm, where he grows wheat, spring barley, winter barley, oilseed rape and maize.

 “Applications of livestock manure promote soil organic matter levels and greatly benefit its biology and structure,” he says. “This regulates moisture, improves earthworm numbers and mycorrhizal fungi populations, leading to more resilient soils,” he says.

About 1,600t of dairy muck is applied each year. A slurry separator is used to split the solid from the liquid waste which makes storing, transporting and applying the high-nutrient product simpler and more cost-effective. A further 6000 m3 of the liquid product is also used.

For forage maize production, about 50kg/ha of the required 150kg/ha N comes from manure sources, whether that’s umbilical spreading from the lagoon or solid muck, saving 6.5t of fertiliser across the 34ha maize area.

“Only minimal amounts of bagged P and K need to be applied on a vari-rate system, which is perhaps our biggest inorganic fertiliser saving,” Mr Jeans says.

Muck is applied ahead of spring barley crops, reducing nitrogen requirements by 15kg/ha, and to oilseed rape crops, where bought-in biosolids have also contributed to savings of 19t of diammonium phosphate across a 120ha area.

“Although OSR yields have been affected by flea beetle larvae, crops seem to withstand attacks well, despite having a lot of the pest in the area,” he says. “We haven’t had to rip any crops up and put it down to our healthy soils, as spreading manure has improved soil fertility and structure.”

© Ben Jeans

Each field is fully soil sampled every four years. The most recent organic matter levels, measured using the Loss On Ignition method, ranged from 4.4% to 9.7%. The Dumas method, carried out on a small number of fields, produced an average of 5%.

“As a result of our healthier soils we are transitioning from a medium tillage system to direct drilling, using a Horsch Sprinter drill with low disturbance openers. We direct drill all our oilseed rape and one third of our cereals, with the aim to increase this. It’s important to ensure our soils are ready and to not rush the process,” he says.

Straw

A proportion of the arable crops grown on farm are used within the dairy herd. All winter malting barley straw is baled for feed and bedding, which means better quality straw for the livestock, without the risk of importing blackgrass-infested straw.

The farm also uses all of its own machinery, which reduces the risk of soil compaction and allows the straw to be taken off the land as early as possible, before the peak harvest period.

Winter barley straw is baled, while wheat straw is chopped and incorporated back into the ground, further promoting soil organic matter levels. Spring barley straw is either chopped or baled and sold off farm, depending on the market.

“With our use of home-produced and bought-in manures and straw incorporation, we like to think of ourselves as net importers of organic matter,” he says.

All grain is sold via the local marketing co-op Salisbury Cereals.

Mr Jeans says he used to crimp grain on the farm for dairy feed, but found the process too costly and time-consuming, as inadequate crimping equipment limited the process. Economies of scale now mean he finds it easier to buy in feed.

Maize benefits

Another priority for Mr Jeans and his father is the strategic integration of forage maize into their rotation to supply a high-energy dairy cow diet, while also creating a more healthy and diverse cropping plan.

With grade 3 chalk soils making up the majority of the farm and just a small 80ha area of heavy clay and 50ha of greensand where the dairy is based, limited spring rainfall means the farm is better suited to growing maize than grass.

This is why Mr Jeans operates an autumn-calving herd on a supermarket liquid milk contract, making maize silage the perfect crop due to its increased forage content.

© Ben Jeans

Maize is also an effective break crop, reducing weed and disease pressures, and is particularly good at grassweed control, where blackgrass prone land undergoes two consecutive maize crops.

“Being a late-drilled crop, maize allows time for a flush of grassweeds to destroy ahead of drilling. We opt for early maturing varieties so we can harvest in mid-September, while the ground is still dry, to avoid wheeling damage to soil structure,” he says.

Four-year grass leys are incorporated into the arable rotation as a means of tackling blackgrass. Problematic areas are sown to grass and later cut for silage, providing a great source of livestock winter feed while also improving subsequent crop yields.

Other mixed farming benefits

Mr Jeans speaks of the many other benefits which his dairy and arable enterprises bring. These include improved cashflow, greater risk management and a more sustainable input flow. He admits that running two enterprises means there is not really a quiet period on the farm, but says the benefits the two systems bring far outweigh this.

“There are great synergies on the farm between enterprises, as labour and machinery is shared. The dairy’s grazing paddocks are planted to arable crops at times, using our arable machinery, to rejuvenate long-term leys.

“We would like to integrate the two enterprises further but because of our 140ha of Higher Tier Stewardship chalk downland grass for youngstock and dry cows, we don’t grow as many grass leys in the arable rotation as we might.”

The diverse working environment helps spread workloads and motivates staff. The farm has three full-time and two part-time workers, and staff retention rates are excellent. Tony Collis is still working part time on the farm after 67 years, while Allen Chalke retired two years ago, aged 87, after working on the farm for 73 years.