New framework ensures swift felling of infected trees

Bookmark and Share Nod tudalen & Rhannu

This news story is now over a year old and information may no longer be accurate or up-to-date. It might also contain obsolete links.
Please use our search link on the left to look for more recent information.

Forestry Commission Wales has devised a new way of working with contractors that ensures it can both react swiftly to the need to fell trees infected with a deadly disease and increase the amount of work contracted out to the forestry industry.

The new procedure, called the Phytophthora Ramorum Infected Larch Harvesting Framework, outlines the terms and conditions that Forestry Commission Wales has agreed with contractors to allow them to start work at short notice to clear infected trees.

Fourteen businesses are on the framework – a mixture of small to medium enterprises, family businesses and sole traders – which were successful in a procurement exercise covering the whole of Wales.

Last year, 876 hectares of Japanese larch trees were found to be infected by an outbreak of ramorum disease in Wales.  Initial findings from surveys this year indicate that this fatal tree disease has infected a further 227 hectares of larch trees in Wales.

Hugh Jones, Head of Forestry Commission Wales’s Harvesting Team, said, “Forest Research scientists advise that, to prevent the disease’s spread, we should fell infected trees to kill the living plant material on which the Phytophthora ramorum pathogen depends.

“Speed is of the essence as, in the autumn, infected Japanese larch trees produce huge quantities of the spores that spread the ramorum disease  - by reacting quickly we can substantially reduce the chance of the disease spreading and thereby protect our forests as much as possible.

“The amount of felling required within this timescale is beyond the scope of our inhouse harvesting teams and this new framework means we can call on contractors at short notice to fell infected trees by harvester or chainsaw.

“Some of the businesses on the new framework have not worked for Forestry Commission Wales before and, as well as establishing relationships with people we have not yet worked with, the framework means we are increasing the amount of work on offer to the forestry industry.”

Most of the larch trees newly diagnosed with ramorum infection this year are in woodlands adjacent to the areas found to be infected last year in the Afan Valley, near Port Talbot. Ramorum disease has also been diagnosed in a small number of larch trees at Bwlch Nant yr Arian, near Aberystwyth, where 60 infected trees were felled in 2010, and, for the first time, near the Alwen reservoir in Hiraethog Forest, north Wales.

Ramorum disease does not harm the timber, and contractors have to follow biosecurity measures during forestry operations to avoid spreading the pathogen. 

Hugh added, "Whilst it is worrying that we have to fell a large number of infected trees again this year, it would seem that our decision to swiftly fell infected trees last year has played a key role so far in managing this major outbreak."

Forestry Commission Wales will continue to undertake surveys looking for the symptoms of ramorum disease until October.

Further information about Phytophthora ramorum is on the Forestry Commission’s website at


1. Ramorum disease of larch is caused by the pathogen Phytophthora ramorum (P. ramorum), which can infect more than 150 species of plants and trees.

2. P. ramorum was first identified in the United Kingdom in a viburnum plant in a garden centre in West Sussex in 2002. It has since been found infecting a wide range of plants and trees throughout the UK. Until recently it had mostly affected shrubs such as rhododendron, camellia and viburnum, but only a limited number of trees; and from late 2008 infection has been found in the environmentally important bilberry plant (Vaccinium myrtillus - known as blaeberry in Scotland and winberry in Wales).

3. In August 2009 P. ramorum infection was confirmed in Japanese larch trees in South West England. This was the first time it had been found infecting a commercially important conifer tree species anywhere in the world, and has since been confirmed in larch trees in all four countries of the UK as well as the Republic of Ireland.

4. Tree mortality is rapid – P. ramorum appears to be able to kill Japanese larch trees within one growing season after its presence is first detectable, which, compared with other tree diseases, is fast acting. In Japanese larch, it causes shoot tips to wilt and needles to turn black and fall prematurely. Cankers that bleed resin can appear on the branches and upper trunk.

5. Infected Japanese larch trees produce particularly high numbers of the spores that spread the disease – much higher than the level produced on Rhododendron ponticum. This means the disease can quickly affect a large number of trees and shrubs. The pathogen can be spread in mists, rain and air currents.

6. P. ramorum is a ‘quarantine’ organism under European Union law, and its presence on trees or woodland plants must be notified to the relevant authorities (Forestry Commission, Fera, Welsh Assembly Government or Scottish Government), who must take statutory action to contain or eradicate it.

7. Forest Research scientists have advised that the most effective means of preventing the spread of the disease is to fell infected trees and plants to kill the living plant material on which the pathogen depends.

8. P. ramorum does not harm the timber, and logs from infected trees can be sold into the timber market, subject to biosecurity measures to ensure that their movement does not further spread the disease.

9. Larch is a durable, versatile timber that tolerates changes between wet and dry conditions very well, resists rotting when used in the ground, and is easily stained, worked and finished. It is therefore in demand for outdoor uses as well as flooring and chipboard.

10. There are about 134,000 hectares (331,000 acres) of larch woodland in Britain: about 5 per cent of the total woodland area.

11. P. ramorum is not harmful to humans or animals, and all public woodlands remain open to visitors, except in areas where felling operations are taking place, which are temporarily closed for safety reasons.

12. P. ramorum causes the disease known as "sudden oak death" in the USA, where a different mating type has killed millions of North American native oak and tanoak trees in California and Oregon. However, its American common name is a misnomer in Britain, where laboratory tests have shown that our native sessile and pedunculate oaks are much more resistant to P. ramorum than their American cousins, and fewer than five native oak trees have been confirmed with P. ramorum infection in Britain. Therefore the generic term ‘ramorum disease’ is used in Britain instead of ‘sudden oak death’.

13. P. ramorum should not be confused with acute oak decline (AOD), which is a separate disease affecting oak trees in the Midlands and parts of Wales and South East England, and in which a newly discovered bacterium species appears to be involved.