Biodiversity with Andrew Hattan of Stonebeck Wensleydale

Our second interview as part of our series on biodiversity and cheesemaking is with Andrew Hattan, of Low Riggs Farm, where Stonebeck Wensleydale is made.

How do you encourage biodiversity on your farm? Is this a priority, particularly in comparison to other sustainability metrics, such as carbon sequestration?

On this particular farm, we have an agri-environmental scheme agreement in place. This agreement is part of the Environmental Stewardship scheme, which runs throughout England. By agreeing to undertake certain environment and biodiversity friendly farming practices we receive an income stream from the UK government.

There are several key themes to the agreement, which include the restoration of upland hay-meadows, heather-moorland, ghyll woodland, dry-stone–walls and the maintenance and restoration of wading-bird habitat.

Taking the hay-meadow restoration as an example, we know that nationally the UK has lost 97% of its biodiverse upland hay meadow acreage since WW2 and the objective of our agreement is to restore the condition of our meadows to their pre-1939 condition. The management prescriptions in the agreement require us to stop using artificial fertilisers and to encourage floral biodiversity in those meadows through the addition of seed, plug plants and by cutting for hay later in the year, after the flowers have set seed. This helps to maintain the diversity of the sward year on year.

By building the diversity we’re putting in the foundation blocks for the food chain locally. Benefits include increased insect life – they’re bottom of the food chain so birds and bats will see a benefit in terms of food supply. The hay meadows also provide a home for small mammals, which subsequently provide food for barn owls and other raptors. We now have two barn owls on Low Riggs Farm.

Biodiversity is not a priority over carbon sequestration, both are equally important. For example, we’re planting lots of trees and want to plant more, creating and extending habitats, food and shelter for birds and other animals; the trees will sequestrate and store carbon over their lifetime as well.

I have concerns about the carbon sequestration story. I feel we have to be very careful in terms of the story we’re telling about grassland and its role in carbon sequestration; whatever we do say needs to be backed up by robust science.

Also very significantly, we have drastically reduced sheep numbers on the farm now that we’re making cheese. The reduced sheep grazing pressure allows for the development of more diverse grassland. Sheep are browsers and selectively graze the sward, removing the more interesting (nutritionally beneficial) plants. These plants have the potential to augment cheese flavours, aromas and textures, if grazed by our cows. In addition an unforeseen benefit of a reduction in sheep numbers has been to allow us to stop using artificial fertilisers completely, which significantly reduces our carbon footprint and saves us money.

Restoration of meadows, woodland, heather moorland etc. – everything is linked together in a mosaic. We’re not perfect but we are doing our best. 

How easy is it for you to track biodiversity on your farm? Is this something you work on in collaboration with universities or other organisations? If so, what species do you monitor and how often does this happen?

We do collaborate with other organisations, yes. We live in the Nidderdale Area of Outstanding Natural Beauty (AONB), which is a protected landscape bordering the Yorkshire Dales National Park. Generally, we have volunteers who come to the farm and undertake a bird survey every year, so we are monitoring ground-nesting bird numbers – we have most of the ground-nesting birds species here – curlews, lapwings, golden plovers, snipe, woodcock etc. I’m very keen to try to keep a handle on what those numbers are doing, partly as it is a reflection on how we farm.

We tend to work with Leeds University, with a PhD student last year looking at carbon sequestration, and one this year looking at nutrient cycling in our soils. Another PhD student about 5 years ago was looking at the potential use of upland grassland in anaerobic digestion for biogas production.

We also monitor the numbers and types of wildflower species in our meadows as part of the agri-environmental scheme. This work is undertaken annually by both ourselves (informally) and local AONB volunteers. Wherever possible we are trying to encourage the use of the land as a scientific or educational resource.

That's exciting about the research into nutrient cycling in your soils, soil health strikes me as something we don't hear so much about (in comparison to wildlife or plant populations for example). Is there enough focus on it, do you think?

Over the past century under conventional agriculture soil health has very much been taken for granted, indeed many soils through out the UK and worldwide have been abused. Agricultural and governmental interest and emphasis on soil health is currently  at an all-time high, but soils are extremely complex, multi-faceted ecosystems that we are only just beginning to understand. In many cases as farmers, our agricultural education is outdated and almost completely ignorant of soil health and we need to catch up ‘big-time’! The organic farming movement, ‘ regenerative' agriculture and the Pasture for Life organisation are all (I believe) consistent with prioritising soil health.

Have you ever monitored freshwater biodiversity on your farm?

We haven’t monitored freshwater biodiversity formally as yet, but this is something that we should definitely be looking at. We do know that there are trout in Stean Beck (into which our farm drains) and we have seen otters there too.

It's exciting to hear that you have been able to cut out artificial fertilisers entirely, have you taken any other action which helps to minimise the impact of agricultural run-off on the local waterways?

Yes, we think so. Much of the Yorkshire Dales landscape is characterised by steep-sided, fast-flowing water courses called ghylls. We have several ghylls on Low Riggs farm which we have been populating with trees over the last decade or so. We use native tree species such as Alder, Rowan, Oak, Willow, Birch, Hazel, Blackthorn etc.. to plant up the steep sides of the ghyll. There are multiple benefits to ghylll woodland establishment including reduction of bank erosion and land-slippage, reduction of run-off, increased water infiltration, prevention of access and pollution of watercourses by animals, shelter, habitat extension, carbon sequestration and improved aesthetics within the landscape.

In addition, because we milk our cows seasonally during the drier part of the year (mid-April to mid-October) and milk once daily, we limit the ‘cow traffic’ in gateways, on concrete and on tracks. We think that this minimises the quantities of soil and manure that may contribute to nutrient-rich run-off. Given our wet climate and delicate peaty soils we do not spread farmyard manure during the winter. This helps to reduce run-off during the winter months.

How many plant species do you have per square meter in your richest field? And how many grass species?

The target is a total of 25 plant species from a sample of four 1m x 1m quadrats in each field. Last time I checked there were around 19 species and we are 15 years into the project! Research work elsewhere has estimated that it will take in excess of 25 years to approach the diversity seen pre-1939. Ploughing and re-seeding the land is not an option here, because of our geography and climate, therefore establishing new plants takes time and a variety of different techniques.

In terms of grass species have meadow foxtail, timothy, Yorkshire fog, sweet vernal grass, annual meadow grass, crested dogstail, cocksfoot, perennial ryegrass and several of the ‘bent’ grass species amongst others.

Do you engage with any funded stewardship programmes?

Yes: our agri-environment agreement is part of the High Level Environmental Stewardship Scheme and we also have an agreement under the English Woodland Grant Scheme. We also have a catchment sensitive farming agreement (water resource protection); and a facilitated group locally looking at environment and biodiversity (through Natural England). We also obtained LEADER funding from Europe to set up the cheese enterprise.

We are hoping that the farm will qualify for the next generation of initiatives under the proposed ‘payment for public good’ philosophy.

What role does reseeding have to play in increasing plant biodiversity, as opposed to changing your fertiliser usage or management of animals on the land?

Good question! We have poorly drained, thin, stony, sloping, acidic soils, a short growing season and a very high rainfall. Ploughing and heavy cultivation of our land in order to reseed is simply not an option – if we did it would all be washed away!

Some of the species that we have in our meadows and pastures have re-appeared on their own, due to the changes in management we have implemented. Because we’ve stopped applying artificial fertiliser and don’t graze with sheep in the spring, the grasses are not outcompeting other plants in the sward and the wild flowers are not being selected out of the sward by the sheep. Things like meadowsweet, betony, and pignut drift back into the meadow from the field edges, which haven’t been grazed or mown as much. We also cut for hay significantly later in the summer, which allows the species to flower and set seed, hence sustaining the diversity for future years.

We have had to buy seeds and plug plants to re-establish the ‘missing’ plant species. We source seeds which are appropriate and which are native to the Yorkshire Dales, often from local ‘donor meadows’. We won’t buy chicory or improved red or white clover, as they are not plants you would find naturally in the Yorkshire Dales. When we do add seed to the meadows it is generally in the late summer, immediately after we have made the hay. We have a very simple system that involves harrowing the grass stubble lightly, broadcasting the seed and then getting cattle and sheep to trample the seeds in over a period of 7 to 10 days. This seems to work well.

What are your thoughts on rewilding?

Whilst Sally and I are not ecologists we are happy to share our views, opinions and ideas regarding re-wilding. From our perspective re-wilding is a ‘damaged’ term that means different things to different members of society and can provoke a great deal of emotion between those in opposing positions. Re-wilding is a process acting on a continuum of land use; to some people re-wilding may be a ‘light touch’ and include the restoration of floral diversity in hay meadows, or the planting of trees, whilst to others re-wilding means the removal of as much human management and intervention as possible, reversion of farmland to scrub/woodland and the introduction of apex predators e.g. wolves, bears, lynx etc..

Our understanding of the term re-wilding is that it is an un-natural i.e. managed, attempt to re-create ‘natural wilderness’…..whatever that means! There are few truly wild (un-managed) places left on Earth where human intervention has not had an impact on nature. These truly wild places (if they exist) are/were characterised by established and complex trophic cascades e.g. food chains, that result in a stable equilibrium over time and exist over a vast scale (perhaps unspoilt areas of the Amazon?).

According to the fundamental laws of physics (which control everything in the universe) managed landscapes require external energy inputs and are therefore considered to be in unstable equilibrium.

An example of an unstable equilibrium could be the habitat that we provide here at Low Riggs for ground nesting birds (Curlew, Lapwing, Oyster Catcher, Snipe, Woodcock, Golden Plover, Redshank, Black Grouse). This is not a ‘ natural' or 'wild' habitat but a managed one. In order to maintain that habitat, we have to cut rushes/bracken or top (mow) grass, graze the fields with cattle and sheep, maintain dry stone walls and fencing (boundaries), apply lime and farmyard manure, maintain drainage and control predators (stoats, weasels etc..). In their most basic form these activities can all be classified as external energy inputs which are necessary to sustain the ecosystem. If society values this managed, unstable equilibrium then it has to accept that these energy inputs are required.

However, if we were to stop managing this habitat in an attempt to ‘re-wild’, then rushes and bracken would very quickly dominate, followed probably by a succession to scrub and woodland. A lack of habitat and abundant predation would put intense pressure on the bird species above (several of which are on the RSPB Red List). However, nature acts in a random way (Random Walk Theory) and cannot be predicted, so therefore, beyond rushes, bracken and initial reduced bird populations, we cannot say for certain how this habitat would 're-wild' over time unless we intervene, which will require further external energy input. Interventions may take the form of tree felling, controlled burning, culling of deer,  fencing, wild-fire control, tree planting etc.. Therefore we could opt to 're-wild' in its purest form, but we would have no control over the end point!

If rewilding is to take precidence over food production from a managed landscape then society has to be comfortable with the writing off of all the (cumulative) energy that has been used to create and manage the landscape previously and the potential for species loss, together with the loss of useful energy output in the form of food production in an era when energy as a resource is becoming significantly more expensive.

So for Sally and I at Low Riggs Farm, whilst we feel unable to adopt re-wilding in its purest form, we are more than happy to continue to plant trees in appropriate places and augment the farm’s managed habitat portfolio and natural capital to encourage as much wildlife and biodiversity as is possible. At the same time we are hoping that we can develop a sustainable business based on maximising added value and minimising purchased inputs.

To what extent is the diet of your herd supplemented by bought in feed?

The majority of modern UK dairy cows consume a diet of forage (grass, grass silage, maize silage, hay e.t.c.) plus concentrate supplement to support milk production of between 7000 - 12,000kg (litres), that are produced over a 10 month lactation. These supplementary feeds consist of cereals, pulses, oilseeds and their by-products, together with additional minerals. Feeding rates depend on level of production and the type and quality of the forage available. Annually quantities of between 1.5 and 3.0 tonnes or more of concentrate supplement may be fed, equivalent to 5kg - 10kg  or more per day during lactation. Generally feeding rates on a per litre basis are somewhere between 200g and 350g of supplement per litre of milk produced. Concentrate supplements in this type of production system can make up between 20% and 45% of the daily feed dry matter intake of the cow during lactation.

Our Northern Dairy Shorthorn cows produce milk seasonally from April to October to coincide with grass growth. They give modest milk yields and are milked only once per day. As a business we are aiming to create a sustainable operation by making the most of what we produce on the farm with the minimum of bought-in inputs, whilst at the same time adding value to our outputs. Last year our cows consumed approximately 100kg of rolled oats each over a 170 day lactation (approx. 600g/day), and gave a total average milk yield of 1430kg (average of 14 cows and 10 heifers). The oats represent approximately 5% of our cows' daily ‘ dry matter’ feed intake. Therefore 95% of our cows’ diet is made up of grazed grass during lactation. On a per litre basis, oats are fed at a rate of  70g/litre. Going forward our targets are to increase milk yield to 2000kg over 170 days and reduce supplementation to 50kg. This will give a feeding rate of 25g of oats per litre of milk produced.

The oats are primarily an incentive to get the cows to come into the milking parlour. One of the major reasons for using oats is that historically they were a major UK cereal crop and would have been perhaps one of the few supplementary feeds available on farms such as ours in the early 20th Century, consistent with the era of our cheese recipe (1920s) and the establishment of the Northern Dairy Shorthorn breed (1940s). The other reason for using oats is that our cows gain all the protein that they need for their modest milk yields from the grass that they eat, so we have no need to purchase supplementary protein e.g. oilseeds and pulses and their by-products. Finally, we know that even when conventionally grown, they require the minimum of inputs. Unfortunately the harsh climate, poor soils, topography and short growing season here in Upper Nidderdale prevents us from growing our own oats.

What do you think of the philosophy espoused by the PFLA and others, that the best diet for ruminants is one that includes only forage and pasture, and no starches or concentrates whatsoever?

Ruminants have evolved to be able to utilise as a primary energy source the cellulose contained within plant cell walls. However, this does not mean that they have not evolved to utilise other forms of carbohydrate such as sugars, which are found within plant cells and starches, which are found within plant seeds. Ruminants can also utilise different types of protein and even fats. This is all possible because of the ruminant's unique symbiotic relationship with the micro flora and fauna contained within its first stomach, the rumen, which is basically a large fermenting 'vat'.

From our perspective there are at least three things that are important here:

The first is that ruminant animals have evolved and/or been bred to convert plant matter that is largely indigestible to humans and other monogastric animals, into useful protein (milk and meat) of high biological value (contains all the essential ammio acids).

Secondly vehicular access to our farm dictates that procuring  large quantities of bought-in concentrate feed is not practical.

Thirdly because our cows' diet is approximately 95% grazed grass then the milk that they produce will be unique and reflective of the plant matter that they consume on this farm. To feed significant amounts of 'imported' concentrate feed would change rumen physiology and microbiology, modify rumen and liver biochemistry and significantly change the nature of the cheese that we produce - aroma, taste & texture. Our cheese would therefore lose it's unique ‘terroir’ and our raison d’etre would be lost!