Social and Economic Analyses of Dothistroma Needle Blight Management

Forest Research

Chris Quine, Mariella Marzano, Lauren Fuller, Norman Dandy, Emily Porth

FERA

Glyn Jones

Independent

Colin Price

University of Bath

Julie Barnett, Gwendolyn Brandon

Social and Economic Analyses of DNB

Forest Research is the Research Agency of the Forestry Commission and is the leading UK organisation engaged in forestry and tree related research. The Agency aims to support and enhance forestry and its role in sustainable development by providing innovative, high quality scientific research, technical support and consultancy services.

Contents

Executive Summary...... 5

Introduction...... 13

Methods

Project team and structure...... 15

WP1: Synthesis and disease management...... 16

WP2: Stakeholder analysis...... 18 WP3: Cost–benefit analysis 20

WP4: Public attitudes towards disease management...... 22

Results

WP1:Building an understanding of disease management...... 23

WP2:Stakeholder analysis and mental models...... 28

Stakeholder analysis...... 28

Mental models...... 29

Expert Panel mental models...... 31

Pinewood managers’ mental models...... 32

Stakeholder survey...... 37

WP3:Cost–benefit analysis...... 39

Timber and carbon...... 39

Public Sensitivity Analysis...... 41

Cases of ‘benefit’ from infection...... 41

Private sector (investment and traditional)...... 42

Other silvicultural strategies...... 42

Spraying...... 42

Overall loss...... 43 Other social and environmental values 43

WP4:Public attitudes towards management methods...... 44

Discussion and synthesis...... 46

Recommendations...... 51

Acknowledgements...... 52

References...... 53

List of Figures

Figure 1- Project structure...... 16

List of Tables

Table 1 – Main factors to influence future forestry...... 23

Table 2 – Main groupings of management options, barriers and motivations...... 24

Table 3 – Four scenarios for the future...... 24

Table 4 – Possible behavioural change and actions...... 27

Table 5 – Example of the value of disease impacts on Corsican pine...... 40

Table 6 – Examples of the value of disease impacts on lodgepole pine...... 40

Executive Summary

Background

  • Dothistroma needle blight (Dothistroma septosporum) is a fungal pathogen of pine trees which is widely distributed across England, Scotland and Wales. It is known to damage exotic pine forests in Britain, and there is growing concern that it will spread to our highly valued native Scots pine. The disease is established in Britain, leaving no option for eradication; however, it is possible to manage forests in a way which will lessen the impact and limit its spread.
  • This project aimed to investigate the social and economic barriers relating to the management of Dothistroma needle blight, to provide a better understanding of the implications of the disease and issues which may prohibit the implementation of effective prevention and control measures.
  • The project addressed four key objectives, contained within the following work packages: WP1 aimed to draw together new social and economic research on the barriers and opportunities of known control options; WP2 aimed to identify the main stakeholders of DNB management, and understand their beliefs, values and practices around control methods and the need for disease management; WP3 aimed to conduct cost–benefit analyses of specific combinations of woodland type and disease status and control so that the economic position is clear and financial barriers are understood; and WP4 aimed to further our understanding of public attitudes towards tree pest and disease control methods.

WP1

  • The primary aim of WP1 was to integrate social and economic research results to provide a synthesis for future disease management. In addition, a Practitioner Panel (PrP) was set up, comprising of around 25 representatives from key stakeholder groups, to help ground the research in a practical context and also to provide opinions, expertise and facts.
  • Six main factors were identified by the PrP as likely to influence the character or health of forests in the UK over the next 10 years: disease development and introductions, economics of disease management, government policy and grants, biosecurity related import control, public support for disease management, and climate change and specificclimate events (e.g. drought or storm).The practitioners and expertsalso provided guidance on the factors likely to influence management options (knowledge, biosecurity, surveillance and response, treatment, forest management, thinning and felling), barriers to undertaking management (affordability, resources, evidence, objectives, technical feasibility, time) and motivations for undertaking management (financial, reputational, timing).
  • The information gained from the PrPwas assessed in three visits to public forests in Scotland, England and Wales. Clearfelling, thinning regimes and diversifying to other tree species were the most commonly employed management methods. Managers generally felt it was too soon to tell if these management options were successful.In some cases the emerging woodfuel market provided income where crops were no longer viable.Key issues raised were: managing harvesting obligations;lack of resources to thin young stands;windthrow; difficulties in finding suitable tree species for site conditions;and the need for better communication networks.
  • The final PrP and communications workshop identified the following top priority stakeholder groups: policy makers and national government; forest owners, managers and workforce; nursery and horticultural trade; and timber processing /timber using industries. A range of desired behaviour changes and possible behavioural interventions to support disease management were developed for each stakeholder group. Incentive schemes and rewards, social norms, feedback systems and emotional appeals were also suggested as ways of supplementing communication and regulation. Overall, there was a lack of common understanding about DNB and a lack of urgency around disease management. A more cohesive message is required to span different sectors, which focuses on positive and proactive promotion of tree health generally rather than on ‘negative’ associations around disease management.

WP2

  • The aim of WP2 was to identify the main stakeholders with an interest or involvement in DNB and to understand their beliefs, values and practices around control methods and the need for them.
  • Through a variety of methods (unstructured interviews with key informants, documentary analysis and literature review), a large number of organisations (almost 50) were identified as having a stake in DNB in the UK. Primarily these were the forest sector and those working in the closely related wood processing industry,land managers, and scientists who carry out survey and diagnostic work. Impacts on these stakeholders included the necessity to revise silvicultural practices, find resources to deal with pests and diseases, and economic loss. Another important group were recreationists and the local community, who experienced restricted access to forest areas and loss of landscape value. However, there is a wide range of potential stakeholders (with an interest in trees), which do not currently have a clear stake, but may well do if native Scots pine trees become heavily impacted.
  • The underlying premise of a mental models approach (e.g. thought processes that shape values and behaviours) is that risk communications must take account of the mental models of the risk issue that are held and shared by the intended recipients of a communication. The mental models approach sets out to compare the models that are held by experts (who are generally assumed to be the party communicating about the risk) with those with whom they are communicating. Mental models were used to compare the models held by experts (forest policy/scientists who communicate about DNB) with those held by stakeholders (the forest managers who receive communications). Overall, the expert models were strongly centered on the key elements of pathology – pathogen, host, and the environment. Forest managers viewed DNB as one challenge among many and identified a much broader range of objectives and influences which the experts did not consider. Factors identified included forest design decisions, species susceptibility, and crown density and humidity. Some managers were concerned about biosecurity and the difficulties of containing introduced diseases and movement of ‘dirty’ equipment between forests by contractors or recreationists. Knowledge levels about disease transmission were mixed.
  • In terms of management, heavy thinning, which is recommended to reduce crown density and humidity, had been taken up on occasion, although two important issues were highlighted: the severe impacts on economic viability of the crop and impracticality of thinning in some areas due to soil and climatic conditions. Monitoring, selecting alternative species, underplanting with different species, premature felling and abandoning sites were also carried out in response to DNB and other tree diseases. There was some support for the option of spraying, although this was coupled with concern about public opposition. Managers are worried about DNB and other pests/diseases and are doing what they can, but they need more evidence and support. Many were uncertain about future options, citing lack of evidence about suitable species choice, past experience of misguided recommendationsor recommendations that have shifted over time, and personal observations on lack of effectiveness of recommended management.
  • A broader set of stakeholders (e.g. consultants in aboriculture and horticulture, local authorities, nurseries, nature reserve management, landscaping and policy) expressed a similar set of concerns as the forest managers, although budgetary constraints and keeping the public happy were considered to be the key challenges. Most stakeholders viewed imports and unrestricted international trade as the main sources of introduced pests and diseases, and a variety of other factors were implicated in their spread, such as poor knowledge and practice within the plant trade, lack of effective treatments, and natural spreading mechanisms. Biosecurity measures were undertaken (sterilisation, washing equipment and clothing, public information notices, tree management), although the lack of resources to implement these and limitations on the ability to consistently apply biosecurity practices were highlighted as problems.

WP3

  • Data and models relating to impacts of disease and consequences of management are limited. However, where information was available, economic modelling was undertaken to estimate the impact of DNB on returns to forestry. Using as a representative baseline Corsican pine of yield class 14 (CP14), infected at age 30, several scenarios were assessed. The criterion used was net present value (NPV), that is, the current equivalent value of future benefits minus the future costs of the activity. Without infection the NPV per hectare, over a 500-year time horizon, for CP14 followed by Douglas fir yield class 14 (DF14) was £49,600. The best case infection scenario was eventually to replace CP14 with a post-infection growth rate 70% of the pre-infection rate, by DF14 (NPV = £45,200). The worst case scenario was CP14 with a post-infection growth rate of 40% not being replaced at all at the end of its rotation (NPV = £1,800). These results highlight the value of replacing crops rather than abandoning silviculture in the face of infection.
  • For a representative lodgepole pine of yield class 8 the losses from killing by infection were also large if no replacement crop was planted(net loss of NPV = £29 000), but less significant if a more productive crop of Sitka spruce replaced it after infection.
  • The sensitivity to carbon prices is dramatic: changes in the pattern of carbon sequestration and volatilisation provide by far the greater part of the estimated social losses (financial and carbon values combined) caused by the disease. Fossil fuel displacement by biofuel, or displacement of high-embodied-carbon structural materials was also important. Crop age at infection had significant impact, with much greater net losses when infection comes early in life. The result was much less sensitive to timber revenues and costs.
  • In terms of ‘benefits’ from DNB, counter-intuitive results have been found if the disease stimulates re-planting with tree species which have higher productivity; or results in delayed sequestration/volatilisation profiles, such that sequestration occurs at a higher value, or volatilisation at a lower one
  • Results for the private sector show substantially smaller losses due to disease than those calculated for the public sector, because of the absence of high-priced carbon transactions. For the CP14 scenario, discounting at 5%: NPV with infection is £4,400 vs without infection £7,200. Discounting at 0%: mean annual earning over 500 years with infection is £336per year vs £349 without it: hence growers might be willing to live with infection in absence of a cheap control option.
  • From the perspective of this analysis, crop spraying, and underplanting and premature felling of infected CP are strategies worth considering, in both the state and private sectors.
  • Although much depends on the responsive strategies adopted by managers, the total of timber and carbon losses to Britain will probably be of the order of £700 million.
  • Willis et al. (2003) estimated the benefits of forestry and woodland in Great Britain for services derived such as recreation, landscape, and biodiversity impacts. Such values are affected by the presence of pests and diseases but not in a simple way. Our review of this paper in relation to DNB indicates that the Willis et al. (2003) study may not provide robust estimates of the impacts, as the effects of any tree pest or disease will depend upon the context of the affected woodland. For example, the impact of DNB on the landscapemay greatly differ between the negative effects expected in a natural Caledonian pine forest compared with potentially positive effects of opening up a managed forest and diversifying the species mix. Thus, applying average values from Willis et al. (2003) would be unreliable, and could be misleading. Helpful values are only likely to emerge through a context-specific evaluation of the anticipated time path of disease and of management responses to it.

WP4

  • The public constitute a number of important stakeholder groups.Not only do they have their own stakes in DNB management (e.g. as residents local to DNB affected forests or recreationists within them), but importantly they were identified by the public and private sector managers as having an influence on their decisions. A nationally representative survey was conducted to assess the acceptability of pest and disease management methods amongst members of the public.
  • Public stakeholders value trees and woodlands for a range of functions, but primarily as a habitat for wildlife. The vast majority want to see action being taken when the health of trees and woodlands is threatened. However, knowledge about tree pests, diseases and management options is low. Evidence shows that involvement in decision-making processes and receiving information on management motivations, practices and implications were important for acceptance of management methods, as well as trust in the source of information and those with decision making powers.
  • The public prefer methods seen as more targeted and ‘natural’ e.g. felling and burning only those trees affected by a pest or disease,or use of biological control. Acceptancewas much lower of chemical applications such as aerial spraying of insecticides and fungicides, the felling and burning of unaffected but susceptible trees or all trees in a woodland or garden. These methods are only likely to receive wider acceptance after less ‘extreme’ measures have been tried and failed.
  • Men and older people are more likely to support management interventions and stronger management methods, e.g. chemical applications, than female and younger people. Acceptance levels can differ according to location and local context (e.g. management is less supported when it may impact on wildlife, whereas support is higher in woodlands that are managed for economic income and financial loss is an issue), experience of disease (e.g. we found that rural respondents can be more supportive of management interventions than urban residents and this is likely to be because rural residents are more likely to have suffered the negative impacts of tree health issues), and values (e.g. those with economic values are usually more supportive of management than those with environmental values).
  • The influence of knowledge on acceptance of management is complex. In some cases, information provision about the impacts of pests and diseases and management methods can generate greater support for management interventions. However, information provision can also serve to reinforce the beliefs of those opposed to management. In order to gain higher support, factual information and management interventions should be tailored to specifically address local dynamics and the values and concerns held by each section of the community although it is acknowledged that additional resources will be required for participatory processes.

Discussion and synthesis

  • Support for tree health management is widespread among a wide range of stakeholder groups from pinewood managers to members of the public; however, the specific details of diseases (e.g. biology of the organism and its mode of dispersal) are often less well understood.
  • Disease management for DNB was not consistently undertaken, despite an awareness of the management options recommended by experts. This was due to a number of barriers including compatibility with existing management objectives, the perceived acceptability of methodsby a wider group of stakeholders, and the perceived efficacy of the recommended methods. Management for DNB is not enforced through regulation, except in nurseries, and is thus more open to individual choice than when action is demanded (e.g. statutory felling). Further research on the efficacy of management measures was viewed as a priority to provide a stronger, more persuasive, evidence base.
  • Affordability and financial constraints were influential in choices over disease management e.g. the direct cost incurred in an operation or the longer term financial benefits of the action.The economic modelling confirmed the unclear nature of the case for management, and exposed an information deficitabout rates of disease spread, effects of increment and mortality, and appropriate growth models.
  • There is uncertainty over what key messages should be communicated about disease management and consequentlythe behaviourswhich should be targeted and themeasures which should be recommended. This is related to a broader state of uncertainty in the forestry sector, whereby the emerging complexities of multi-faceted environmental change expose significant information deficits within a system with an historical focuson forest expansion based on a narrow technical specification and simple investment model.
  • The diverse mix of stakeholders impacted by and influencing disease management in the UK requires a context-specific set of measures depending on the groups and forest system in question. There was a dichotomy between those who see disease management as requiring a technological solution and those who perceive current tree health problems as reflecting the need for a comprehensive rethink in the policy and practice of forestry (e.g. species choice, diversification, broadening of objectives, acceptance of disease as part of ecosystem dynamics). Resolution of this dichotomy will build on experiences gained in management of current outbreaks and will require further development of collaborative approaches to knowledge exchange and decision making (including at national and local scales).
  • Priority areas of development are: 1) stronger evidence for efficacy of disease management measures; 2) development of economic models including assessing public benefits of trees and forests, realistic scenarios of disease development and crop types within which to explore the financial case for disease management, improved modelling of growth rates post infection, and of infection development and impact on mortality; 3) an improved communication strategy and targeted messages to the major stakeholder groups alongside the development of deliberative/participatory processes to incorporate stakeholder perspectives/different contexts.
  • Overall there is a need for future development of forestry practice to deal with uncertainty and emerging threats, including new decision-making frameworks that take into account climate change and threats of disease, and to identify the key players best positioned to lead a new forest management culture.

Introduction