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Summary: Mature forests have structural habitat features that can take hundreds of years to develop, and large reserves alone are unlikely to ensure conservation of the species that rely on these features. This paper outlines a proposed new approach to managing mature forest features, the ‘mature habitat management approach’, in areas outside of reserves. The objective was to maintain a network of current and future mature forest habitat distributed across the landscape. The approach is designed to complement the existing reserve network and management actions and is tenure‐blind. Spatial information on the availability of mature forest habitat at the local (1‐km radius) and landscape (5‐km radius) scales is used for decisions on retention within a 1‐km radius of a harvest area, to reach the minimum target of 20% and 30% retention of mature forest at the local and landscape spatial scales, respectively. We believe this approach could contribute to meeting the conservation needs of many species that require mature forest features for refuge and breeding in Tasmania and elsewhere. [ABSTRACT FROM AUTHOR]

Introduced pathogen microorganisms are important drivers of ecosystem change. This paper highlights the impact of the non-native pathogen mildew multi-species complex on the natural regeneration dynamics of pedunculate oak (Quercus robur). Pedunculate oak is a European keystone tree species, hosting a great amount of biodiversity, but its future role in (near-)natural forests is uncertain due to the lack of natural regeneration. We reviewed historical and recent ecological, pathological and forestry literature on topics related to the impact of mildew on the success of advanced natural regeneration of pedunculate oak in (near-)natural forests. We propose a novel hypothesis, the 'pathogen mildew hypothesis', to explain the failure of natural regeneration of pedunculate oak. Mildew reduces shade tolerance and vertical growth in seedlings and saplings, so sapling vitality and competitiveness have diminished considerably since it was unintentionally introduced to Europe in the early 20th century. Due to mildew infection, pedunculate oak in many cases no longer regenerates well naturally under its own canopy. We found that forest ecologists and conservationists often overlook the impacts of this 'recent' driver, while the 'closed-forest' and 'wood-pasture' hypotheses do not adequately help the management of pedunculate oak regeneration. Nature conservation and forest management plans should thus also consider the impact of mildew in order to improve natural regeneration, promote close-to-nature management of pedunculate oak forests, and support associated diversity. More generally, nature conservation, forest ecology and close-to-nature forestry should pay greater attention to the impact of introduced non-native microorganisms on the dynamics of natural ecosystems. Unlabelled Image • Ecologists and conservationists often overlook the impacts of alien microorganisms. • An alien microfungus impedes natural regeneration dynamics of a keystone species • Oak powdery mildew reduces shade tolerance and growth in seedlings and saplings. • Proposed hypothesis explains the failure of natural regeneration of pedunculate oak. • The alien microfungus threatens the rich biodiversity associated with oaks in Europe. [ABSTRACT FROM AUTHOR]

Forest area has dramatically increased since the beginning or middle of the 19th century in European countries. At least half of the forests present today have grown on formerly cultivated lands, pastures or heathlands. However, net forest expansion largely masks a slow but irretrievable erosion of ancient forests. Meanwhile, forest resource harvesting (biomass, litter) has fundamentally changed during the last two centuries, moving from intensive biomass removal to increased growing stocks in different European countries. This article reviews the current knowledge on the long‐term legacies of past land use and forest management practices and their effects on the functions, diversity and composition of understory vegetation of current forest ecosystems. First, we define the concepts of forest continuity and ancient forest. Then, based on the French case, we present the advances in historical sources, which make it possible to better reconstruct the change in land use and forest management practices over the last two hundred years. We review how understory plant communities and their traits respond to forest continuity and to different types of former agricultural uses, both at local and landscape scales. We then address three important issues for conservation and management: the conservation value of ancient forests, the impact of forest management on the ecological integrity of ancient forests, and the under‐explored legacies of former forest management practices on soil and understory vegetation. Lastly, we propose five main fronts for future research efforts: (a) explore all types of cartographic, written sources and environmental markers; (b) develop modelling approaches to understand how past land use shapes plant communities; (c) better define the conservation value of ancient forests in conservation and management policies; (d) investigate how drivers of global change interact with forest management and land use legacies and (e) explore land use legacies in mountain and Mediterranean socio‐ecological systems. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Human activity is known to greatly influence species occurrences. In forest ecosystems, biodiversity is often believed to be influenced by two habitat characteristics: (1) forest continuity, related to a minimum length of time in a wooded state since a threshold date; and (2) stand maturity, related to the availability of late‐developmental‐forest attributes. In a context of ongoing global biodiversity loss, qualifying the effect of past and present human activity on forest ecosystems while taking into account variations in abiotic factors is of primary importance for conservation. Location: Temperate mountain forests in the Northern Alps. Method: Based upon a sampling design crossing forest continuity (ancient vs. Recent) and stand maturity (mature vs. overmature), and while controlling for the effect of two major environmental factors, soil and climate, we explored the individual response of saproxylic beetle, springtail, herbaceous plant and epiphytic macrolichen species to past and present human activity. Results: Forest continuity influenced the occurrence of relatively few species, indicating that past land use had almost no legacy effect on the species occurring in the study forests today. In contrast, stand maturity had an overall positive effect on species occurrences. However, our results showed that species occurrences were more obviously influenced by abiotic conditions. Indeed, beyond the effect of continuity and maturity factors, the probability of presence of numerous species was best explained by climate and soil. Main conclusions: Overall, we show that species occurrence was more influenced by stand maturity than by forest continuity, but also that site‐specific characteristics were of great importance in explaining the probability of presence for numerous species. In the ecological context of alpine forests, these findings emphasize the need to better control for climatic and edaphic conditions in order to (1) improve accuracy in predicting species occurrence and (2) better design areas of conservation interest. [ABSTRACT FROM AUTHOR]