Ben McCarthy of Plantlife, Ruth Borthwick of the creative writing charity Arvon, Minette Batters of the NFU, Graeme Willis of the CPRE, Tracy Worcester of Farms not Factories and Gwyn Jones of RUMA respond to reports on the increase in intensive factory farming of poultry, pigs and cattle in the UK

The “unnoticed” expansion of mega-farms raises serious concerns about farm animal welfare and our food system (Mega-farms transforming UK countryside, 18 July). Even less visible is the air pollution generated by intensively housed animals and the devastating impact it is having on nearby wildlife.

At high concentrations, such as from these mega-farms, ammonia and other nitrogen emissions cause direct damage to lichens, mosses and other plants, including bleaching and discolouration.

In polluted, nitrogen-rich “fertile” conditions more vigorous, “thuggish” species thrive, making it near impossible for more sensitive wildflowers to survive. Plants known to be particularly at risk from air pollution include harebell (Campanula rotundifolia), which was recently classified as near-threatened in England, and bird’s-foot trefoil (Lotus corniculatus), which supports more invertebrates than any other herb. Soil fungi and their dependents, including many cherished orchids, are also especially vulnerable. Species richness depletion from air pollution has knock-on effects for bees, birds and all the other wildlife which depend on healthy plantlife.

The “march of US-style mega-farms” is of great concern given that more than 90% of wildlife hotspots in England and Wales already have nitrogen levels higher than they can tolerate. While statutory agencies and many local authorities are taking limited action, they need better funding and support to give this issue the attention that it deserves.

Air pollution is the “elephant in the room” of farming and nature conservation – it deserves a place at the table as we decide the future of UK food and farming as we exit the European Union.

Ben McCarthy

Director of strategy, Plantlife

• On 4 April 2017 Shropshire county council granted permission for a poultry unit on farmland housing up to 100,000 chickens. The land is adjacent to The Hurst, a writers’ retreat run by national creative writing charity Arvon in the Shropshire Hills countryside close to Clun. Poet laureate Carol Ann Duffy describes Arvon as “the single most important organisation for sharing and exploring creative writing in the UK”.

The Grade II-listed Hurst, built in 1813, and a former home of playwright John Osborne, underwent a £2.3m renovation in 2013 supported by Arts Council England. It has a significant effect on the local economy as over 800 people come to Arvon’s writing courses and retreats held there each year. Eight permanent staff are employed at the 19-bedroom house and 26-acre estate. It is estimated that over £170,000 is spent by Arvon each year in the area, purchasing food and services from local suppliers and tradespeople, such as food suppliers and caterers, cleaners, taxi drivers, plumbers and builders.

However, over the course of our objection to the plans to erect this inappropriate mega-farm in the Clun valley, we came up against officers and councillors who held fast to a regressive and philistine view of the countryside as a site of intensive agriculture at any price, waving aside the undeniable new economic model that is thriving under their very noses. They prefer an unsustainable system which ships its feed thousands of miles from the Americas and destroys our hedgerows with 44-ton lorries driving at dead of night.

John Osborne called the view from The Hurst “probably the best view in England”. No longer, if Shropshire county council gets its way.

Ruth Borthwick

Chief executive and artistic director, Arvon

• The picture painted in your article would be completely unrecognisable to most British farmers. While the farming sector is evolving to meet a growing demand for food, it is also the case that the number of farms has decreased in the past few years.

What hasn’t changed is the high quality, safe, traceable and affordable food being produced by British farmers to exacting welfare and environmental standards. The key thing for any livestock farmer is the health and welfare of their animals. And as veterinarians and the farmers themselves can testify, farm size is not a measure for the welfare of an animal. What does impact on animal welfare is the quality of management and stockmanship that farms operate to.

UK farmers are leaders in good husbandry and high animal welfare and environmental standards which are grounded in robust science and innovative technology – all of which plays a major role in balancing the need to produce more British food in a way that is sustainable environmentally, economically and socially.

Minette Batters

Deputy president, National Farmers Union

• It is welcome to see the new Defra secretary, Michael Gove, argue that the retained public funding for agriculture should reward environmental benefits rather than land ownership.

A settlement based on environmental and public benefits, however, will not necessarily hasten the death of small family farms (Editorial, 24 July). For the first time in recent memory, a secretary of state is talking about small family farms rather than just production and growth. At last, we are having more discussions about how the market supports the industry.

Further, we now have the opportunity to introduce a new funding model that protects farms of all sizes alongside the much-improved delivery of environmental benefits. The government can investigate ways to introduce tiered models of funding that recognise the different economies of scale for farms, or reward a progressive approach to husbandry across the whole farm.

Graeme Willis

Food and farming campaigner, Campaign to Protect Rural England

• The demand for humanely raised pork is rising steadily as people become aware of the appalling cruelty and reckless overuse of antibiotics in factory pig farms and the toxic stench suffered by people unfortunate enough to live near one of the 800 mega-farms in the UK. Some 40% of sows in the UK live permanently outdoors – a fact conveniently ignored by industrial farming lobbyist Zoe Davis, from the National Pig Association, when she stated: “There aren’t many producers that farm pigs outdoors because there’s not a huge demand.” The reader can help bring an end to this onslaught of cruelty by looking for high animal welfare labels. For pigs that is RSPCA Assured, Outdoor Bred, Free Range and Organic. To help understand why this meat tastes better, look no further than the Farms Not Factories website, where famous chefs explain why they would only ever serve meat from high animal welfare farms. It is more expensive, but not after a true cost analysis looking at the antibiotics given to factory-farmed animals to stave off disease. Antibiotic-resistant diseases reach the neighbouring community and beyond on the meat, and bring us all ever closer to the day when antibiotics won’t work to cure basic human diseases. A recent survey found antibiotic resistant E coli on 63% of factory-farmed pork in UK supermarkets. To spread the cost of buying high welfare, eat less but better meat and avoid diseases related to overeating meat like obesity, diabetes, heart disease and colon cancer.

Tracy Worcester

Farms not Factories

• Reports on “mega-farms” persist in linking large scale farming with high antibiotic use – despite featuring poultry farmer Richard Williams, who says no antibiotic has been used on his site since it was set up two years ago (About 42,000 birds inside – and a sweet, sickly smell outside, 18 July).

Richard is not alone. Since 2012, members of the British Poultry Council’s Antibiotic Stewardship scheme, representing more than 90% of UK poultry meat production, have achieved a 71% reduction in total antibiotic use. The latest UK data highlights a 10% fall in antibiotic sales for farm animals. Sales of highest priority antibiotics to farming have also fallen, and new pig industry data shows use of colistin dropped by over 70% between 2015 and 2016 – despite UK farming already being one of the lowest users in Europe.

It may suit campaign groups to add antibiotics to the list of issues they have with larger-scale farming, but resorting to global or European data and analogies because the UK data doesn’t back their case is disingenuous. Iin the UK, scale of farming is not a factor in antibiotic use.

Gwyn Jones

Chair, Responsible Use of Medicines in Agriculture (RUMA) Alliance

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