Developing and evaluating strategies to increase the material utilisation rate of hardwoods: a hybrid policy Delphi-SWOT analysis

The indigenous hardwoods in German forests have a substantial ability to store carbon, and forestry reconstruction measures are anticipated to result in an increase in availability of hardwood on the wood market. Despite this, its material usage is declining with over two thirds of the harvested quantity being used for energy production. This study aims to identify policy measures and promising strategies for increasing hardwood utilisation using a combined policy Delphi-SWOT approach with literature review undertaken to identify the barriers and driving factors for an increase in its material use. The results were then ranked by a panel of experts and used as basis for the SWOT analysis, which was then applied to an extended SWOT approach. The resulting strategies were then discussed by the panel and ranked further in the 2nd and 3rd Delphi round. After three Delphi rounds, three strategies and associated policy recommendations were ranked as most effective by the experts: innovative hardwood products including manufacturing processes, research transfer and lobbying. This study provides both strategic analyses and effective strategies to stimulate the production of hardwood-based products and ends with a concise description of these strategies and policy recommendations, which are benchmarked against current literature and best practise examples.


Introduction
The European Green Deal aims to shape a circular bioeconomy since forest ecosystems are a key in reaching the goals of climate neutrality, sustainable products (EC 2019), and long carbon captures (Sillanpaä and Ncibi 2017). The material use of low-value forestry by-products achieves better economic and ecological results than the use for energy production (Lu and El Hanandeh 2019). Wood-based products "can provide additional carbon storage services and a substitution for carbon-intensive materials and fuels" (EC 2018). The climate mitigation potential of hardwood remains high since the direct energy utilisation from it is substantial (Weimar 2011;Mantau 2012;Bösch et al. 2015). The sustainable utilisation of wood is crucial in preparing the ground for resource-efficient, circular bioeconomy (FAO 2018) and mitigating climate change (Winkel 2017;Toppinen et al. 2020;EC 2019). Supporting companies and industries in the development of new products and production processes can strengthen the circular economy in the wood-based sector (Da Silva et al. 2020).
In Germany, indigenous hardwood forests have abundant wood supply potential, which is still increasing as a result of forest reconstruction (BMEL 2017). However, development of marketable hardwood products remains challenging (BMEL 2017), hardwood-based value-added products are still rare (Stängle et al. 2015;Kühle et al. 2019;Teischinger 2019d) and are not diffuse within the market. The Charter for Wood 2.0 (BMEL 2017) places great emphasis on the potential of value-added hardwood products (Purkus and Lüdtke 2020), but strategic analyses and development of effective strategies stimulating the production of hardwood-based products are still missing. They are, however, essential for the transition towards a wood-based bioeconomy (Purkus et al. 2018).

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However, Hurmekoski and Hetemäki (2013, p. 17) see "potential advantages in complementing the current modelling approach dominant in the forest sector" by Delphi combined with strategy development, evaluation and implementation. In a wood-based bioeconomic context, Delphi studies and SWOT analyses have been conducted highlighting different strategic topics, such as forest sector transformation towards a forest-based bioeconomy and its limitations, and future prospects for the forest energy industry (Pätäri et al. 2016;Pätäri 2010;Toppinen et al. 2017;Falcone et al. 2020;Brunnhofer et al. 2019;Hurmekoski et al. 2019). To improve the reliability and validity of the results it is worthwhile combining Delphi with other qualitative or quantitative methods (Turnbull et al. 2018;Hurmekoski and Hetemäki 2013). Complex challenges in forest management and multiple stakeholder interests require the application of more than one method in order to improve the strategic planning process (Pesonen et al. 2001;Di Lallo et al. 2016;Kajanus et al. 2012).
Therefore, a hybrid policy Delphi-SWOT study was applied to analyse the German hardwood sector from a strategic perspective, and to evaluate strategies facilitating the material use of hardwoods in order to identify promising strategies and the necessary policy measures.

Material and methods
A hybrid policy Delphi-SWOT methodology was considered suitable for capturing the complexity of a sector affected by the direct and indirect influences of political, economic, ecological and social factors (Loë et al. 2016;Turoff 2002).
SWOT (Strengths, Weakness, Opportunity, Threats) analysis was developed in the 1960s (Pesonen et al. 2001). It is a common and successful management tool for strategy development in the forestry and wood sector (e.g., Rauch 2007;Gerasimov and Karjalainen 2008;Rauch et al. 2015;Štěrbová et al. 2016). However, the isolated use of SWOT as strategic management tool casts some doubts on its effectiveness (Pesonen et al. 2001).
The Delphi method was introduced in the 1950s by the RAND Cooperation in cooperation with the U.S. Air Force. It is now used for forecasting and decision making in many disciplines (Rowe and Wright 1999;Okoli and Pawlowski 2004).
Delphi is applied during complex discussions to facilitate consensus among experts (Linstone and Turoff 2002) and takes the form of a survey conducted multiple times with revision options (Landeta 2006). Individuals are able to change or to adapt their opinion through the rounds based on feedback, without losing face in their peer group (Rowe and Wright 1999). Delphi fits to large groups of experts, who are geographically dispersed (Rowe and Wright 1999) and has been proven to be a sound method for the systematic investigation of complex situations where data is lacking (Toppinen et al. 2017). Since consensus, in the context of this paper, is not primarily needed, the Delphi process stops after obtaining sufficient information for the development of strategy and policy measures. Figure 1 summarises the methodological approach combining SWOT and Delphi techniques that is described in depth in the following subchapters.
Since "online" is the best method of conducting a policy Delphi (Turoff 2002), this study followed the guidelines for conducting an e-Delphi (cf. Cole et al. 2013). Questionnaires were developed and pre-tested by persons not involved in the panel (cf. Delbecq et al. 1975).

Participant panel
Personal involvement, commitment of participants regarding the study´s topic and their motivation to be part of the study are significant for a study's success (Landeta 2006;Delbecq et al. 1975). Participants do not need to have expert knowledge in each topic of the Delphi study, since it is more desirable to combine various experts' opinions (Turoff 2002) to fully appreciate the scope of the hardwood supply chain (Rowe and Wright 2001). Thus, the participant panel was designed to be as heterogeneous as possible (Fig. 2) (Loë et al. 2016;Turoff 2002). Rowe and Wright (2001) argued that 5-20 people with heterogeneous backgrounds are reasonable, whereas Okoli and Pawlowski (2004) state 10-18 participants are required. Turoff (2002) however, considered approximately 10-50 people in each group as appropriate in policy Delphi studies.
Participant selection was basically carried out according to the Knowledge Resource Nomination Worksheet procedure (KRNW) (e.g., Brunnhofer et al. 2019;Delbecq et al. 1975;Okoli and Pawlowski 2004) as follows: preparation of the KRNW, population of the KRNW, nomination of additional people, ranking of participants, and invitation. In the first step, the groups (A) forestry, (B) industry, (C) governmental organisations (GO), NGOs, NPOs, and associations, and (D) research, were identified. In a second step, members of groups (A)-(C) were recruited based on internet research and personal/institutional contacts and ranked based on the following criteria: balanced demographics within the participant group and expert knowledge of producing and processing products together with the application possibilities of hardwood. Group (D) participants were identified by Google Scholar research, European and German project databases (http:// www. cordis. europa. eu and http:// www. foerd erpor tal. bund. de) based on keyword searches (e.g., "material utilisation", "hardwood", and "wood"). Researchers fulfilling the selection criteria (research concerning hardwoods in forestry, in wood processing or development of wood-based 1 3 product with at least a doctoral degree and working in Germany, Austria or Switzerland) were ranked according to the number of publications registered in Scopus (http:// www. scopus. com). As recommended by Delbecq et al. (1975), the first nine participants in the ranked group lists were contacted and invited to the online questionnaire. After approximately two weeks, the next nine people were invited. If the number of questionnaires answered per group reached a value between 10 and 18, the invitation process was stopped, otherwise more people were contacted.
Participants were handled in a quasi-anonymous way, as every person completing the questionnaire in the prior round was invited for the next round (cf. Haynes and Shelton 2018) using pseudonyms. The quasi-anonymous survey and pseudonym allocation were supported by the software QuestorPro.

Strategic analyses
To gain an overview of the barriers and driving factors influencing hardwood material utilisation, a literature review was conducted. From the results obtained (Tables 2 and 3), 26 drivers and 31 barrier statements were identified and delivered to the participant panel within the 1st Delphi round. Participants stated their opinion as to what extent a driver or barrier contributed to the increase in hardwood material use by applying a five-point Likert scale. Participants could add additional drivers and barriers to ensure that the main drivers and barriers were captured by the panel as required in a policy Delphi (Turoff 2002).
The 1st Delphi round took place during November and December 2019.

Strategy development
The SWOT-framework was applied since it aims to identify competitive advantages and the factors influencing strategy (Pickton and Wright 1998). SWOT factors were deduced from the ranked drivers and barriers of the 1st Delphi round by transferring them to internal strengths/weakness and external opportunities/threats of actual hardwood utilisation (Tables 4 and 5). Factors in each SWOT field were limited to maximal six (Lombriser and Abplanalp 2018) due to limited possibilities for strategy development.
To create strategies based on the SWOT analysis, the extended SWOT approach was applied. Logical strategy combinations concurrently maximizing strengths and opportunities or minimizing weaknesses and threats were scanned within the SWOT matrix. The following questions were used to identify strategies (Lombriser and Abplanalp 2018): The potential SWOT combinations result in four generic strategy types: 1. SO-strategy: internal strength can be utilised in order to take an external opportunity (ideal case), 2. WO-strategy: internal weakness is reduced in order to realise an external chance, 3. ST-strategy: internal strength is used to reduce an external threat, 4. WT-strategy: internal weakness is reduced to mitigate external threat (worst case).
As suggested by Lombriser and Abplanalp (2018), for each strategy the underlying SWOT issues were listed accordingly applying the following nomenclature. For example, S1/O3 added next to the developed strategy means that this strategy mainly relates to the strength listed in the first position (#1) and opportunity listed in the third position (#3) on the SWOT table (cf. Rauch 2017).
The strategies thus developed were presented to the panel for evaluation and discussion within the 2nd Delphi round. Additionally, extended descriptions of the strategies as well as new strategies could be added.
The 2nd Delphi round took place between December 2019 and January 2020.

Strategy evaluation
In the 3rd Delphi round, participants checked the developed strategies and implementation measures. Afterwards, the panellists evaluated the strategies according to the following criteria: desirability (regarding efficiency and benefit), priority, feasibility, likelihood of implementation, and impact (cf. Turoff 2002), applying a five-point Likert scale.
Finally, panellists ranked alternative strategies with respect to their overall ability to increase the utilisation of hardwoods as an economically useful material. This procedure facilitated the estimation of impacts, consequences and acceptability of the strategies developed as required for a policy Delphi (Turoff 2002).
The 3rd Delphi round took place during February and March 2020.

Strategy and policy measures recommendations
Panellists commented on and added to the results of the 1st and 2nd Delphi rounds. In the 2nd and 3rd Delphi round, they gave their opinions on the strategies and measures created. Based on panellists' votes and comments after the 3rd Delphi round, the authors substantiated the specific strategies and measures to provide policy guidance for implementation.

Results and discussion
3.1 Participants 56 people, of which 51 men (91%) and five women (9%), participated in the first Delphi round. Table 1 shows the development of the number of participants of the three Delphi rounds.

Drivers and barriers to increasing the material use of hardwoods
Literature review results were clustered, and drivers (Table 2) and barriers were extracted. On the barrier side (Table 3), some conflicts must be considered: firstly, nature conversion approaches restrict wood harvesting and the increasing wood utilisation (Bolte et al. 2016a); secondly, competition for material versus energy use of the resource and for traditional versus new products (Bolte et al. 2016b).
Participants evaluated to what extent drivers and barriers contribute to the potential increase in hardwood material use. Table A1 and Table A2 in Supplementary Information list the 15 highest ranked issues.

SWOT and strategy development
Factors within the SWOT categories were ranked according to the ratings of 1st Delphi round (cf. Table A1 and  Table A2). Factors O4 and T5 as 1st round comments were rated within the 2nd round. Thereupon, factor T5 was evaluated as the most significant threat (Table 4).
Applying the extended SWOT approach, 12 strategies to increase the hardwood material use were deduced (Table 5).
In the second Delphi round, the participants rated the strategies which had been developed (Table 6). Strategy     (2017) Use for energy production Hardwood primarily used for energy production, especially within private households, subsidies for bioenergy production biasing markets, low cascade utilisation  W2 Domestic value added of hardwoods-especially for roundwoodand the number of cascades is low S3 Hardwood suitable for material use is sufficiently available W3 Technical process adjustments to increase the material use of hardwoods are not profitable S4 High level of hardwood processing competence W4 Forestry sector lacks economic sale options for hardwoods, which could be processed to products W5 Seasonality of hardwood supply and non-transparent material and information flows Opportunities Threats O1 Hardwoods improve the sustainable performance of the wood value chain T5 Low domestic demand for hardwood products (especially in the construction sector) O2 Climate change promotes (mixed) hardwood forests T1 Cheap fossil resources disadvantage wood-based biorefinery products O3 Supply difficulties for coniferous woods T2 Lack of national and international strategies to promote the material use of hardwoods O4 Alternative energy production methods reduce the contribution of (hard) woods in bioenergy production T3 Subsidies for bioenergy production distort the market price of hardwoods T4 Supply volatility due to external risks (e.g., calamities, enlargement of protected areas, lack of qualified workers) descriptions and policy measures could be added by the participants.
Participants added strategy #13 Circular Economy in the 2nd Delphi round. This strategy aims at increasing the cascade of wood utilisation through greater use of waste wood, in the sense of a closed loop economy, to raise the potential of biogenic resources.

Strategy evaluation
By analysing the extended strategy descriptions and comments of the participants, further aggregation of the strategies as a basis for the strategy evaluation within the 3 rd Delphi round was possible (Table 7).
With reference to the four participating groups, four significant correlations were found in the evaluation of the five strategies (Table 8). Strategy #2 was rated by group (D) in the criterion "likelihood of implementation" significantly lower than the other three groups did. The other three significant correlations were identified for group (C) indicating that members of group (C) perceive their own core competence of lobbying for the interests of their members as very important and uprated appropriate strategies (e.g., support for targeted marketing of results, image campaigns).  Figure 3 shows a comparative evaluation of the strategies according to the evaluation criteria.

Formulation of strategies and measures
In the following, a compilation of participants' comments and suggestions on the three best ranked strategies and their corresponding measures is provided for policy guidance to facilitate strategy implementation.
Strategy #2* innovative hardwood products including manufacturing processes turned out to be the key strategy in increasing the material use of hardwood. Due to the wide range of product possibilities, intensive research and development of innovative, high value products (e.g., laminated veneer lumber, platform chemicals such as succinic acid or levulinic acid, composite materials, medical devices) is recommended by the experts. They also emphasis to develop new hardwood construction materials which are compatible with conventional manufacturing processes.
As was stated by an expert: "It is important to have a "whole tree utilisation concept"-i.e., the possibility of using as many assortments as possible-sawn/peeled wood-industrial wood-crown wood with a correspondingly good increase in value. Due to the enormous range of product possibilities the focus on a promising concept (with new products and applications) must not be lost." One challenge identified by the experts was the high heterogeneity of hardwoods, and the currently low wood potential (e.g., maple, birch, ash,) compared to native softwood species has to be overcome to achieve economic product and process development and to create a critical demand quantity. Therefore, mixed hardwood pulp was suggested to be investigated more deeply. The experts described the following specific measures to implement strategy #2*: • Providing information on the availability of hardwood species in the market to both the public and potential investors, an in-depth study of hardwoods' supply potential, classified by technology-specific assortments.  Although research transfer (Strategy #8) is a standard requirement for publicly funded R&D projects, the experts believe that this transfer should be more effectively used in transferring research to companies. However, from a governmental perspective, experts suggested a reduction in the dependency of research on project-related third-party funding. The establishment of incentive systems based on, for example, the sustainability portfolio, full reusability business models, and regionally manufactured hardwood products (e.g., in public procurement) is recommended to promote the transfer of research results into industrial applications.
The experts described the following specific measures to implement strategy #8: • Promoting knowledge transfer by integrating practitioners in research projects from an early stage on (e.g., as steering group) together with obligatory feasibility studies as a research funding criterion. • Mandatory coupling of research and industry partners (team-up) in the case of public funding in applied and experimental research and promoting a practice-oriented research culture as well as a corporate culture with an affinity for research. • Bridging the financing gap between the end of research projects and product market launch, offering support for micro-enterprises and start-ups to overcome the socalled "Valley of Death". • Accelerating the marketing of results to specific interest groups, to lower the inhibition threshold for the purchase of hardwood products and creating market incentives.
Strategy #10* lobbying aims at joint initiatives by the forestry and the timber industry to pursue innovative utilisation paths (e.g., biorefineries). Therefore, the experts identified three main fields of lobbying activities: 1. A carbon tax on products based on product life cycle assessments to promote short distances and regional production. An accredited certification scheme for the implementation of measures has to be developed in cooperation with all relevant institutions based on standardised data and compensatory measures. 2. Promotion of the use of wood in construction to overcome discrimination of wood as a building material compared to other building materials, particularly in legal standards. Timber construction acts as a long-term carbon-store. New taxation schemes must be accompanied by its legal adoption of (federal states) building regulations as well as model building codes and standards to promote the use of high-quality hardwood, especially for load-bearing purposes.
3. Marketing of results to specific interest groups to lower the inhibition threshold for the purchase of hardwood products and to create market incentives.
The experts described the following specific measures to implement strategy #10*: • Establishment of coordination offices (e.g., support for the implementation of hardwood in construction projects, recommendation by experts, and support of forest owners). • Funding of a platform to build up a hardwood supportive network. • Target group-specific networking, for example promotion of hardwood to architects in education and training, trade fairs, the public; promotion of wood-based (platform) chemicals. • Campaign for the use of wood as a material in general, pointing out the advantages compared to for example steel and plastics and for wood use and forest management as sustainable measures against climate change. • Promotion of business models aiming at full reusability through appropriate pricing/subsidy incentives. • Regulations to increase the use of regionally produced and manufactured hardwood products in public procurement (construction, interior design, office furniture, equipment, uniforms, etc.) as a model and positive example for society.

Discussion of developed strategies and measures
Study results point out that to increase hardwood material use, new products have to be developed (strategy #2*) and for some already developed product prototypes, the innovation process of transferring research results into industry production is missing and has to be supported (strategy #8). Furthermore, both strategies need a coordinated and supportive network of research, industry and policies as recommended by the panel experts in strategy #10*. Implementing strategy #2* the portfolio of wood-based products is anticipated to expand further in the future (Hurmekoski et al. 2019;Buehlmann et al. 2010;Temmes and Peck 2020) and higher value-added hardwood products research is seen as a promising pathway to convert higher proportions of wood into longer-life products (Temmes and Peck 2020).
For Switzerland, options for a higher utilisation of domestic hardwoods are accepted within the building industry where specific norms and approvals were, as with this study, recognised as barriers. Existing norms are also seen as major barrier in the panel and chemical industry (Krackler et al. 2010;NFP66 2017). Similarly, in the US, laminated veneer lumber (LVL), pulp and wood panels are seen as utilisation possibilities for low-quality hardwood (Luppold and Bumgardner 2003). The need to develop innovative hardwood products (cf. strategy #2*) has been noted in France, where the abundance of hardwood resources is not fully utilized (Lenglet et al. 2017). Wolfslehner et al. (2013) showed positive effects of a higher material utilisation rate for smalldiameter hardwoods on both value added and sustainable regional development in Lower Austria. For Canada, it was shown that low-quality hardwood assortments offer a serious potential for adding further value to the wood value chain by the production of high value-added products, for example betulin (Hassegawa et al. 2018). Strategies such as widening the range of products or supplying certified products were identified as ways to transform the US hardwood mass market to a more diversified niche market (Buehlmann et al. 2010). This is mostly in line with the herein suggested future hardwood utilisations.
In line with findings for Italy, France and Austria (Falcone et al. 2020;Lenglet et al. 2017;Wolfslehner et al. 2013), reliable information regarding hardwood supply potential was seen as essential for the development of innovative hardwood products by the German experts involved in the Delphi study.
Confirming the study´s results, hybrid products using low-quality hardwood such as mixed hardwood LVL Nguyen et al. 2020, innovative mixed-hardwood pulp (Olsson et al. 2019), and mixed soft-and hardwood pulp (Fišerová et al. 2019) are actually under investigation.
New fields for the application of hardwoods are driven by the sustainability and climate mitigation debate. For example, the application of various hardwood-based materials in the automotive sector (e.g. Müller et al. 2019;FNR 2020) has the potential to become a mass volume market but is only currently considered as research topic. Therefore, research transfer strategies (strategy #8) are required in order to accelerate innovation.
Pushing research transfer (strategy #8) as recommended by the experts in the Delphi study requires mutually respected information policy between academic research and industry to avoid over-engineering by academics or an untimely early focus on techno-economic benefits by companies. Successful innovation requires the integration of different stakeholders and balanced information policies .
As described in strategy #10* support for networks and cooperation is strongly recommended overcoming crosssectoral cooperation barriers. It is essential to both strengthening wood-based bioeconomy projects Lettner et al. 2020) and raise capital for large-scale cooperative efforts . Systems assessing environmental and social aspects have to be developed to initiate fiscal measures that adjust the market mechanisms supporting bioproducts and their production systems (Stafford et al. 2020). Therefore, carbon tax on products, is a measure recommended by the Delphi experts, as an appropriate policy instrument to ensure sustainable production on a global level (Aldieri et al. 2019;Aryapratama and Pauliuk 2019).
In line with the results of this study and the policy measures recommended, public procurement is seen as a motor for promoting multi-story wood-based constructions like Wildspitze in Hamburg (Germany), wooden highrise (HoHo) of Vienna (Austria), Canada Earth Tower in Vancouver (Canada) (all three timber hybrid construction methods) or the highest wooden high-rise Mjøstårnet in Brumunddal (Norway).
The experts emphasised the requirement of research funds for product development and innovation transfer. Consequently, it may be worthwhile investigating the possibility of green finance for this purpose.
Strategies #2*, 8, 10* and 4 are in line with the recommendations on potential development for hardwoods by Knauf and Frühwald (2020) such as: building up industrial manufacturing capacities with optimized processes, a joint professional industry marketing for hardwood in both the forestry and wood industries and research funding for reducing barriers to the use of hardwood. This and the Knauf and Frühwald (2020) study reached similar conclusions but utilized slightly different methodical approaches. The policy measures identified herein contribute to the range of policies promoting bio-based products as considered in the European Green Deal (EC 2019) and as formulated by Ladu et al. (2020): climate mitigation combined with sustainable forest management (referred strategies #2*, 4, 10* and 13), and R&D policies (referred strategies #2* and 8), and awareness raising (referred strategy #10).

Reflections on the study design and future needs
A potential limitation of the study is the decreasing number of participants in the later Delphi rounds. Even though the panel was compiled very carefully, the bias of the participants cannot be fully excluded. However, we considered it important to form a relatively large panel composed of people with solid, relevant expertise (starting with > 50 people). The policy Delphi was conducted in three rounds, and new strategies were raised within the Delphi process (e.g., strategy #13). However, these did not get the same attention as the first-round topics. Although this is a well-known disadvantage for Delphi studies in general (Turoff 2002), it had negligible impact in this case.
Further well-known limitations of expert studies applying to this study are overrating the importance of one's own field of expertise and the fact that radical new ideas for a sector are typically not developed by their existing stakeholders (Egfjord and Sund 2020). An example is the limited adoption of biorefinery technologies by pulp and paper incumbents, which seems to result from a lack of the competencies and partnerships required for this as well as a preference for improving the existing technologies. (Hansen and Coenen 2017). Even though wood-based biorefineries have the potential to use almost all wood components as a base material (textiles, nanocellulose, composites, lignin-based binders, chemical building blocks) (Stafford et al. 2020), such innovative products were only partly considered by the expert survey.
Another disadvantage of the passive Delphi method is that experts do not discuss directly with each other (Mendoza and Martins 2006) and tend to defer consideration of possible future scenarios, for example bioenergy market development and climate change impacts (Hurmekoski et al. 2019). Accordingly, in the first Delphi round, the utilisation of hardwood as fuel was strongly emphasised as a barrier to higher material utilisation, but in the final strategies, energy production based on hardwoods was disregarded.
Another limitation is that panellists were only from German speaking regions restricting the generalisation of findings to a global level. Opening up the focus for example, to the main hardwood countries in Europe (e.g., Slovenia, Romania, France, Poland) could be a topic of future research.
Furthermore, gaining a deeper understanding of causality and system dynamics within a hardwood-based circular economy (cf. path dependency of key factors, e.g., forest ownership, forest management, policy framework (Hurmekoski et al. 2019)) is highly recommended as a topic for future research.

Conclusion
This paper is focused on the strategies needed to stimulate the material use of hardwood in the whole sector of the forestry and wood industries. To sufficiently support product innovation as the most important strategy, a coordinated interaction of several other strategies is recommended. As an example, a national hardwood strategy would provide a supportive funding and policy environment as well as the need for changes at the highest level. With this, the hardwood sector would be eligible for attractive alternative financing schemes, such as Green Finance. Developing innovative products and associated production technologies are most important and so, research and innovation transfer must be continuously improved.
This study scrutinized shareholder perceptions to strategic analyses and development of effective strategies to stimulate the production of hardwood-based products. Results obtained and policy recommendations derived affirm the objectives of the Charter for Wood 2.0 regarding the necessity of promoting the production of hardwood products and increase its material use.
The three strategies developed herein and their associated policy recommendations were selected by expert ranking after three Delphi rounds. These were: innovative hardwood products including manufacturing processes, research and innovation transfer, and lobbying. This substantially extends the Charter of Wood 2.0's approaches regarding hardwood valorisation.
This study ends with a short and concise description of strategies and policy measures benchmarked against current literature and best practise examples. The applied hybrid policy Delphi-SWOT approach proved to be adequate for strategy development and evaluation at an industry sector level.
Acknowledgements Veronika Auer is grateful for the support received from the Conference of Women's and Gender Equality Representatives at the Bavarian Universities (Landeskonferenz der Frauen-und Gleichstellungsbeauftragten an Bayerischen Hochschulen (LaKoF)) within an educational program.
Funding Open Access funding enabled and organized by Projekt DEAL. Veronika Auer is grateful for the support received from the Conference of Women's and Gender Equality Representatives at the Bavarian Universities (Landeskonferenz der Frauen-und Gleichstellungsbeauftragten an Bayerischen Hochschulen (LaKoF)) within an educational program.

Availability of data and material
The anonymised data that support the findings of this study are available on request from the corresponding author Veronika Auer. The data are not publicly available since they contain information that could compromise research participant consent.

Conflict of interest
The author declares that there is no competing interest.
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