Research Update
Forest Research’s annual update was delivered at Roslin on 17 March. The Forest Research annual update was attended by some 25 delegates who were welcomed by the morning session chairman, Steve Penny, Scottish Liaison Officer for Forest Research. Steve reminded the delegates of the wide range of information that can be accessed through the FR website www.forestresearch. gov.uk and encouraged the use of the advanced Google facility to help search for specific items of interest.

The first presentation by Steven Hendry was an update of information on red band needle blight, its cause and the way in which the infection is spread by its various dispersal mechanisms. Steven then identified both the geographic areas currently being infected and those most likely to become infected in the near future.

To help with recognising the various symptoms, which are evident through the seasons, a series of helpful photographs were included in the presentation. The susceptibility of the various species was listed and alternative species likely to be resistant to the blight were suggested. The presentation ended with practical advice on the management and control of crops already infected and a warning against underestimating the impact the blight could have on production.

Steven summarised the situation thus:–
• The disease has increased rapidly since the late 1990s and is now present in much of the UK.
• The host, pathogen and environment all favour the disease.
• Significant volume loss and mortalities will impact on timber revenues.
• Future management will have to involve changes in species and silvicultural practice.
• Policy issues will arise surrounding forest sustainability, global plant trade and climate change.
(Note: Forest Research has published a research note, FRC002, on the subject.)

The second presentation, by Roger Moore, gave useful information on a range of pests and offered advice on recognising when trees are in distress. When suspect trees are identified, best practice involves doing an initial investigation and reporting all the evidence to Forest
Research (www.forestresearch.gov.uk/fr/INFD-5UWEY6) who will be able to offer the help required.

The help available includes Hylobius management support, in the form of software which allows the nature of the problem to be confirmed, as well as information on a series of Hylobius MSS workshops being held throughout the UK. The presentation then dealt with the threat from the pine-tree lappet moth which is one of the most serious defoliators in Europe. It included a brief history of outbreaks over the years, and explained the rather unusual life cycle which involves a descent by the larvae from the canopy to over-winter in the ground
litter before ascending back up the tree in spring.

Prior to 2004, all moths identified were in the southernmost parts of the UK and were confined to males who, on their own, did not constitute a threat of breeding, but more recently pine-tree lappet moths have been identified near Inverness, as have distressed trees showing damage typical of that caused by the moth. As a result of this a survey has been set up and is already underway to further examine this potential problem. The survey
involves the examination of the ground litter for the over-wintering larvae, and the use of glue bands on the trees to entrap the larvae when they climb back into the tree crown during spring. This is very much an ongoing piece of work and further updates will be made available in due course.

Gregory Valatin delivered the next presentation entitled Is Forestry Carbon Undervalued? which, in light of the imminent government discussion paper on the forestry aspect of this subject, was especially appropriate. The presentation considered the various perspectives on forestry carbon such as its possible inclusion in carbon cap-and-trade schemes and discussed how the government’s quality assurance scheme could be extended to cover better forestry
credits. After the various types of carbon credits were explained, tables were shown listing the various offsets for both British and overseas projects and their respective website references. After looking at approaches to carbon valuation the presentation considered the market values of carbon, the average prices that prevailed during 2007, future carbon values and the social and market discounts.

Gregory’s concluding remarks suggested that forestry carbon was currently undervalued, and that there was potential for additional financial benefit to the industry, as well as social benefits, if the schemes were extended to include forestry carbon. However, there was little
evidence that the UK government‘s proposals on carbon accounting will do anything to realise this potential at the present time. This makes the industry’s participation in responding to the impending government discussion paper on valuing carbon absolutely essential.

The following websites give useful background information to the above presentation:–
http://journals.sfu.ca/int_assess/ i n d e x . p h p/ i a j / a r t i c l e / v i e w-File/272/236
http://www.hm-treasury.gov.uk/tax_ env_GESWP140.htm

The afternoon session was chaired by Bill Mason who introduced Colin Edwards whose presentation was entitled Using Stand Structure to Determine Management Prescriptions in Native Pinewoods and advocated the use of a ‘model’ technique. Colin stressed that it was essential for a clear understanding of the specific sustainable objectives to be established before starting to use the model. Next, it was necessary to generate the information required for the structural phases of the stand to be identified through tree count, distribution and growth comparisons over a period of time. As well as counting the number of species of tree, the process has to take into account seedlings, saplings, damaged trees, deadwood, both fallen and standing, and ‘crown form index’.

By superimposing the management and natural interventions into the model proffered by Colin, a useful indication could be obtained of how the stand reacted to them. From this information the model makes it possible to extrapolate the likely responses to future interventions. This allows for the selection of the intervention most likely to encourage the stand to adapt and produce the required sustainable objective.

The presentation concluded by showing a worked example based in Glen Affric where the advice recommended by the model was that more intensive thinning should be practised to develop later successional stages and so achieve the desired outcome of developing old growth. Bruce Nicoll presented an update on the work done by himself and Tom Nisbet on developing guidance for site selection and best practice for stump harvesting. The relevance of this work is the Scottish government’s commitment to a target of 31% of energy requirement to be met by renewable sources by 2011 and the consequential increasing demand for forest residues.

Considering that a stump represents 25% of a tree’s volume, and that a clearfelled site yielding 60 tonnes of brash can also yield 150 tonnes of stump-wood, stump harvesting demands serious consideration. Approximately 3000 tonnes are currently being harvested in South Scotland by excavators fitted with a custom-built head which uproots the stump, and breaks it down before wind-rowing to facilitate drying.

After due time the stumps are then forwarded to roadside to await road transport to the E-on power plant at Lockerbie. The guide, which will be published at the beginning of May,
identifies, explains and classifies the four principal risks to soil sustainability as:–

• Increased soil damage due to compaction, rutting and disturbance leading to erosion and
increased turbidity and siltation of local watercourses.

• Removal of essential major- and micronutrients, leading to lower soil fertility, and potential loss of tree growth in subsequent rotations.

• Removal of base cations reducing soil buffering capacity and leading to increased soil and stream water acidification.

• Increased carbon loss from disturbed soil after stump harvesting leading to reduced site carbon storage.

The guidance, which is based on expert judgement of the scientific issues and informed practical experience, also outlines the necessary site environmental risk assessment and gives advice on site organisation and additional considerations. Bruce concluded his presentation by explaining that work on the subject was continuing with a view to further increasing the precision of the advice on offer. www.forestresearch.gov.uk/stumpharvesting

The final presentation, Aspen – a Neglected Species in Scottish Forestry, was delivered by Alan Harrison. Alan first gave a brief ecological outline of the species which is regarded as one of the earliest ‘natives’ along with birch, willow and rowan. The presentation then explained that historically it was used as medicine (aspirin), animal fodder, and in the making of hand-worked furniture, baskets and other woven articles, but its palatability to browsing animals, poor seeding and short life span were amongst the reasons for its current low status and scattered distribution.

However, closer examination of the aspen’s properties indicated that it did potentially have relevance to today’s markets for sawn timber, composites and high quality paper manufacture and this led to this work being undertaken in 1995 by Forest Research.

The location and design of the clone trials were explained, the results presented and interpreted, and conclusions were drawn that aspen should be a greater component of British woodland, not only because of its high environmental and biodiversity value but because hybrid aspen has significant potential for utilisation as a productive species, particularly for fibre and biomass. Jim Christie.