Some different sheep at the magical Challacombe

I was up at Challacombe Farm yesterday afternoon for a site visit to see and discuss the work of Naomi Oakley and Mark Owen who farm this Duchy Farm. It was a field visit which was part of a 2 day workshop entitled ‘Locally led agri-environment schemes – from a farmer’s perspective.’ I’ll report back on the workshop at a later date – in the meanwhile here are a few photos I took at Challacombe.


Naomi showing the extent of her farm and its large number of associated archaeological features.


Reporting back on the bracken management project


The slopes of the valley showing the Mediaeval lynchets – see here for more details on these.


From the barn up the valley to Hameldown Tor


In the barn Naomi shows of three different breeds of sheep which are being kept for their wool – the little dark one at the front is a Black Wensleydale – a very rare breed – see here. The white sheep at the back are Wensleydales – see here.


The sheep with the black and white faces are Zwartbles – famous for producing  an excellent fleece – really good to see wool coming back into profitability again (assuming you use the correct breeds) – see here for more details.


Here are a few Wensleydales out on an in-bye pasture.And this a hardy Welsh Black Mountain Sheep – small but very efficient at grazing around the Scheduled Ancient Monuments.

We also visited the amazing Rhos pastures at Challacombe –  wet valley mires – in the summer they are buzzing with life – I’ve written about these before – see here and here.

 

Finally …. can really recommend this book – tells the amazing story of sheep in Britain – from the times when wool created the country’s wealth right through to the dominance of sheep for lamb. The last chapter won’t be to everyone’s taste as Philip Walling is clearly very angry of the recent controversies regarding ‘overgrazing’ and the subsequent reduction in the national sheep flock. The book though does give a wonderful introduction to sheep breeds, where they came from and where they now survive.

A great afternoon at a magical place.

The problem with bracken

Bracken (Pteridium aquilinum)  is a contentious species which is almost universally hated on Dartmoor (except in the handful of places where it harbours the nationally threatened butterfly, the High Brown Fritillary (Argynnis adippe).

Bracken was once harvested as an important crop and used for animal bedding and as a roofing material. These practices dropped out of favour as other more modern materials were used instead and as a result bracken was no longer managed and began to spread.

This spread of bracken can be damaging to the historic environment as its dense network of rhizomes can seriously interfere with any sub-surface archaeology. It is also a species which is very unpopular with hill-farmers as it spread reduces the area of palatable grazing for livestock. Likewise conservationists do not like the species as its spread can reduce areas of inherently interesting vegetation communities e.g. heather stands (Marrs and Watts 2006).

bracken

Bracken tends to grow on deep well drained soils which do not become waterlogged. As a result it is absent on Dartmoor from the blanket bog and wet heathland communities as these are too wet. These deeper better drained soils on the moor support heathland (NVC H8 Calluna vulgaris-Ulex gallii heath) and upland grassland communities (NVC U4 Festuca ovina-Agrostis capillaris-Galium saxatile grassland and U5 Nardus stricta-Galium saxatile grassland). Bracken can encroach into wet heath communities (M15b Trichophorum cespitosus, Erica tetralix wet heath and M15d Trichophorum cespitosus, Erica tetralix wet heath, Vaccinium myrtillus sub-community if these have become drier as a result of hydrological changes, over grazing or burning (Marrs and Watts 2006).

These National Vegetation Classification (NVC) communities can change depending on the management regime they receive. Averis et al (2004) suggest the following changes to National Vegetation Classification communities which can all lead to an increase in bracken communities. The communities described below follow the NVC (Rodwell 1991 & 1992).

  • If H8 Calluna vulgaris-Ulex gallii heath or H12 Calluna vulgaris-Vaccinium myrtillus heath is over grazed or over burnt it can change into M25 Molinia caerulea-Potentilla erecta or U4 Festuca ovina-Agrostis capillaris-Galium saxatile
  • If U4 Festuca ovina-Agrostis capillaris-Galium saxatile grassland or U5 Nardus stricta-Galium saxatile grassland are under grazed then can turn to H8 Calluna vulgaris-Ulex gallii heath or H12 Calluna vulgaris-Vaccinium myrtillus heath
  • However all four of the communities mentioned above (H8, H12, U4 & U5) can be invaded by bracken and turn into U20 Pteridium aquilinum-Gallium saxatile

Bracken can be controlled either by cutting, rolling or the use of herbicides (asulam). However treatments must be repeated yearly if bracken is to be controlled, complete eradication is usually not possible. All these methods are time consuming and expensive. Rolling is often not possible due to the terrain or rocks and asulam can now only be used under an Emergency Authorisation licence as its use was outlawed in 2012 [1], there are also concerns that stocks of asulam are not in short supply as it is no longer being manufactured.

bracken-bruising-003Bracken rolling on Dartmoor by the National Trust

Pakeman et al (1995) showed that bracken had increased significantly over the past few centuries in Britain but they also showed that between 1970 to 1980 there had been a 3.4% decrease on Dartmoor (by 1.9km2 of bracken being gained but 3.8km2 being lost).

Pakeman et al. (2000) ‘concluded that the current abundance of Pteridium was less than, or at worst, equivalent to maximum historical records’. It is clear therefore that the abundance of bracken has fallen and risen depending on its harvesting or clearance by humans.

Werkman et al (1996) carried out experiments where bracken and heather and a mix of the two were grown in open topped tents to mimic climate warming and where different plots were treated with additional nitrogen inputs. They found bracken growing in the tents with additional nitrogen grew more vigorously and for a longer growing season than plants not grown in tents where no nitrogen was added. The bracken under the former conditions also encroached into the heather stands.

Werkman et al (2002) in another experiment found that bracken responded positively to increased temperatures but did not respond to increased nitrogen levels. They concluded that in a warmer climate bracken will continue to replace heather. They added a caveat that if climate change led to drier summers then water could be a limiting factor in the spread of bracken.

The implication of both papers by Werkman et al (1996, 2002) is that bracken will also spread into areas of upland grassland as well as areas dominated by heather.

Hill-farmers and other land managers on Dartmoor such as the National Trust spend considerable time and money attempting to control bracken on the moor, it would appear that in the future more effort will be required if bracken is not to spread further.

So rather like Purple Moor Grass Molinia caerulea, bracken does respond to anthropogenic changes to the atmosphere. In the case of bracken to increased temperatures caused by rising CO2 levels and in the case of Molinia to increased nitrogen levels caused by pollution from vehicles and agriculture (see here).

If a future climate change scenario on Dartmoor led to rising temperatures and reduced rainfall it is not impossible that the current areas of wet heath and those areas dominated by Molinia could become dry enough to allow the encroachment of bracken into these areas too.

 References
Marrs R.H. & Watts A.S. (2006) Biological Flora of the British Isles: Pteridium aquilinum (L.) Kuhn. Journal of Ecology 94, 1272–1321
Pakeman, R.J., Le Duc, M.G. & Marrs, R.H. (2000) Bracken distribution in Great Britain: strategies for its control and the sustainable management of land. Annals of Botany, 85B, 37–46.
Pakeman, R.J., Marrs, R.H., Howard, D.C., Barr, C.J. & Fuller, R.M. (1995) The bracken problem in Great Britain; its present extent and future changes. Applied Geography, 16, 65–86.
Rodwell J.S. (ed) (1991) British Plant Communities. Volume 2. Mires and heaths. Cambridge University Press. Cambridge.
Rodwell J.S. (ed) (1992) British Plant Communities. Volume 3. Grasslands and montane communities. Cambridge University Press. Cambridge.
Werkman B.R. & Callaghan T.V. (2002) Responses of bracken and heather to increased temperature and nitrogen addition, alone and in competition. Basic and Applied Ecology 3: 267-276.
Werkman B.R., Callaghan T.V. & Welker J.M. (1996) Responses of bracken to increased temperature and nitrogen availability. Global Change Biology 2: 59-66.

[1] http://www.brackencontrol.co.uk/asulam

National Sheep Association – Hard Brexit should not sacrifice sheep sector

There is a letter in today’s Farmers Weekly by Phil Stocker of the National Sheep Association about how the sheep sector could be seriously affected by a hard Brexit and the loss of subsidies.

nsa

There can’t be a hill-farmer in the country who is not deeply worried

Last year the NSA published a document about sheep in the uplands – I don’t agree with all of it but it is good and worth a read – download it here.

A tale of two lambs

I went deliberately to Waitrose yesterday in search of some English lamb mince – what I thought would be straightforwards turned out not to be so. No English lamb at all of any sort was to be found, instead the shelves were full of New Zealand lamb …… This led me to investigate why this might be.

waitrose-nz-lamb

It is quite complicated! Firstly as a nation we don’t eat that much lamb and mutton – apparently about 5kg per person per year – see here, and we are basically self sufficient in lamb. Defra told us that the national sheep flock in 2015 was estimated to be around 23.1 million animals – see here and Monbiot calculated that sheep occupy around 4 million ha. of land – the majority in the uplands – see here.

So if we are self sufficient in lamb why do we import lamb from New Zealand?

Firstly UK sheep farmers export around the same amount of lamb / sheep products as the UK imports (which mostly comes from NZ). So if we didn’t import lamb there wouldn’t be the supply to meet the demand.

Secondly lamb is a seasonal product, the UK is in the northern hemisphere whilst of course NZ is in the southern hemisphere. As a result their seasons are complimentary. UK lamb is mainly available from June – December, whilst NZ lamb is in season from December to early June.

Thirdly, as a nation we are rather fussy about what cuts of lamb we like to eat, we tend to prefer legs and chops, as the result of this the rest of the meat cuts and products are exported to countries abroad where ‘lesser’ quality cuts are eaten. In addition much more lamb is eaten that mutton in the UK.

Fourthly, is the issue of currency rates. When Sterling is strong then lamb is uncompetitive on the continent and UK exports drop. However when Sterling is strong, this is the time when NZ wants to export lamb to Britain as they get good prices for their products, leading to a potential conflict with UK farmers – see here for an example from Wales.

Conversely when Sterling is weak (as now) lamb becomes competitive on the continent and exports rise, but imports from NZ drop.

Lamb is a favourite Easter food and of course at this time UK lambs are still growing on the hills and in the fields so the lamb that is available is from NZ and this has led to people asking why UK supermarkets don’t stock UK lamb – see here.

Interesting! But there is more …..

Sheep and lamb 1

People often complain that lamb is very expensive and why should this be the case? Well a comparison with pigs and pork explains quite a lot. The average sow produces  8 piglets on a four month cycle and each piglet after 5 months will weigh 250lbs and can go to market. Pigs can be kept in a pen measuring 30 x 30 feet. By comparison a ewe can produce 1 – 2 lambs per annum and needs 0.75 acres per animal.

Finally, look how this might change after Brexit – the pound is now very low compared to where it was 7 months ago so conditions are ideal for UK farmers to export to the Continent and elsewhere – both markets come courtesy of the EU Single Market.

If negotiations to secure exporting access to foreign markets takes many years then UK farmers won’t be able to export.

The strategy for sheep farming may then have to change – one option might be, especially in the lowlands, to produce lambs which are less seasonal. For example Dorset Breed sheep can produce lambs throughout the year so an increase in this breed might allow lamb to become available all year round.

Difficult times ahead.

 

 

A plan for Britain?

In case you missed the fuller details here is the 12 point plan that Theresa May announced yesterday regarding the UK’s decision to leave the EU – entitled ‘Plan for Britain’.

  1. Provide certainty about the process of leaving the EU
  2. Control of our own laws
  3. Strengthen the union between the four nations of the UK
  4. Maintain the Common Travel Area with Ireland
  5. Control of immigration coming from the EU
  6. Rights of EU nationals in Britain and rights of British nationals in the EU
  7. Protect workers’ rights
  8. Free trade with European markets through a free trade agreement
  9. New trade agreements with other countries
  10. The best place for science and innovation
  11. Co-operation in the fight against terrorism
  12. A smooth and orderly Brexit

Pretty disappointing not to see either the environment or climate change specifically mentioned.

The New Economics Foundation published a short response to the speech – here and it suggested that the government’s plan would lead to reduced workers’ rights and watered down environmental protection.

screen-shot-2017-01-17-at-22-42-26

Donald Tusk, the EU President issued this tweet

Quite a lot of people on Twitter were suggesting that May was trying to ‘have her cake and eat it’, but I guess you have to start  the process somewhere.

There is a long process ahead now and let’s hope it doesn’t just lead to a cliff edge.

 

 

Reaction to Theresa May’s Brexit speech

Various representatives of the farming industry have been expressing their opinions after Theresa May’s speech on Brexit where she clearly stated that we will not be in the Single Market or part of the Customs Union. See here.

Here are the views of the National Farmer’s Union.

Here are the views on a ‘hard Brexit’ (which is what we are getting) from the National Sheep Association.

Sheep

Whilst it had been trailed that we would be leaving the Single Market, the reality is now beginning to sink in.

Upland farmers in particular must be in shock.

It is now very difficult to predict what is going to happen next – nothing I suspect until Article 50 is triggered in March and then maybe nothing substantive until a ‘deal’ is done.

That’s a long time to wait immersed in uncertainty.