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Abstract: Heterobasidion annosum sensu lato (s.l.), Armillaria ostoyae, and Phellinus sulphurascens are economically important fungal pathogens in temperate forests of the northern hemisphere that cause decay, growth reduction and tree mortality of coniferous hosts. Fungal inoculum residing in roots and stumps after final felling can remain viable for decades and place stands at an increased risk of mortality in subsequent rotations. Stump removal is one strategy that can be used to reduce the impact of root rot fungi in regenerating stands. This paper presents results from five long-term stump removal trials in Canada, Denmark, and Sweden. In all studies, stumps were extracted and larger roots removed. After a period of time ranging between 21 and 50years, tree mortality, infection or both caused by A. ostoyae, P. sulphurascens and H. annosum s.l. was compared between stumped and non-stumped areas. In all but one trial, efficacy of stump removal to reduce disease occurrence over the long-term was 80–100% for A. ostoyae, 85–100% for P. sulphurascens, and 20–72% for H. annosum s.l. Stump removal for H. annosum s.l. was more effective in the Swedish trial than in the Danish trial, but in both locations the frequency of root disease increased with tree age. Results from trials indicate that stump removal is effective in reducing disease incidence and likely improves site productivity in subsequent rotations. Forest managers should consider stump removal as a routine operation when harvesting, especially on sites that have high hazard for A. ostoyae, P. sulphurascens, or both. Even though stump removal can provide adequate control against H. annosum, use of the biocontrol agent Phlebiopsis gigantea on freshly cut stump surfaces after harvest and following thinnings is perhaps a more cost effective control measure to reduce the frequency of H. annosum rot in next rotation forests. New initiatives involving harvesting of stumps for bioenergy may offer the additional benefit of minimizing disease impacts in next rotation forests. [Copyright &y& Elsevier]

Abstract: The substitution of biomass for fossil fuels in energy consumption is a measure to mitigate global warming, as well as having other advantages. Political action plans for increased use exist at both European and national levels. This paper briefly reviews the contents of recommendations, guidelines, and other synthesis publications on sustainable use of forest biomass for energy. Topics are listed and an overview of advantages, disadvantages, and trade-offs between them is given, from the viewpoint of society in general and the forestry and energy sectors in particular. For the Nordic and Baltic countries, the paper also identifies the extent to which wood for energy is included in forest legislation and forest certification standards under the “Programme for the Endorsement of Forest Certification” (PEFC) and the “Forest Stewardship Council” (FSC) schemes. Energy and forest policies at EU and national levels, and European PEFC forest standards are analysed. With respect to energy policies, the utilisation of wood for energy is generally supported in forest policies, but forest legislation is seldom used as a direct tool to encourage the utilisation of wood for energy. Regulations sometimes restrict use for environmental reasons. Forest certification standards include indicators directly related to the utilisation of wood for energy under several criteria, with most occurrences found under environmental criteria. Roles and problems in relation to policy, legislation, certification standards, recommendations and guidelines, and science are discussed. [Copyright &y& Elsevier]