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A correction of this article has been published in: Forestry: An International Journal of Forest Research, Volume 94, Issue 3, July 2021, Page 477, https://doi.org/10.1093/forestry/cpab015; International audience; The translation of genetic gains into economic gains is important for evaluating the impact of using genetically improved forest reproductive material (FRM) in the forest sector. However, fewstudies based on European forests have been published to date. Here, we analyse the stand-level wood production and financial performance of planting genetically improved FRM in even-aged planted forests focusing on four European case studies with advanced breeding programme material and different management contexts: Scots pine (Pinus sylvestris L.) in southern Finland, central Sweden and central France, and maritime pine (Pinus pinaster Ait.) in southwestern France. The growth of improved stands was simulated using species-specific growth models by incorporating two levels of expected genetic gains (present and next generations of seed orchards, varying from 7 to 40 per cent depending on the breeding programme) into the estimated mean annual volume increment over a rotation (m3 ha(-1) yr(-1)). For each level of genetic gain, we tested the plantation of improved FRM managed with two silvicultural scenarios (maintaining the standard baseline rotation and thinning regime vs shorter rotation through the earlier achievement of the recommended felling criteria) in comparison with the plantation of the reference unimproved material (absence of genetic gain) managed according to the standard silvicultural regime. The use of improved FRM resulted in a larger financial performance in terms of soil expectation value (SEV (sic) ha(-1), discount rate 3 per cent) than planting unimproved reference material in all case studies and silvicultural scenarios for different wood price contexts (SEV gain from +20 to +190 per cent depending on the genetic and silvicultural context). The challenges associated with the economic assessment of realized gains fromgenetically improved FRM are discussed. We argue that silvicultural guidelines should be adapted to the use of improved FRM in order to gain better financial performance and flexible silvicultural response of planted forests to future environmental and socio-economic changes.

The IPCC previsions for the upcoming decades include an increase in frequency and intensity of drought events in several regions worldwide, including Northern Europe. Drought significantly affects forest ecosystems through decreased productivity, increased vulnerability to biotic disturbances and increased subsequent mortality. How forest ecosystems maintain resistance and resilience to drought events are important questions. Our study aimed to assess whether species mixture or an individual tree size within a stand alters a given tree’s resilience and resistance to drought. A retrospective study of tree-ring widths allowed us to calculate resistance, resilience and recovery indices for five recent drought events: 1976, the 1990–1992 period, 2003, 2006 and 2010. These drought events were selected based on the SPEI (Standardized Precipitation Evapotranspiration Index) drought index. Our study sample consisted of 108 individual sessile oak ( Quercus petraea (Matt.)) or Scots pine ( Pinus sylvestris L.) trees sampled in 2012 and 2013 (Orleans forest, central France) in pure and mixed stands, divided into three diameter classes corresponding to three sizes: large, medium and small trees. Scots pine performed better than sessile oak during the 1990–1992 and 2010 droughts while the contrary was observed for the 2003 and 2006 droughts. They performed equally in 1976. We suggest that the differing sensitivity of the two species to spring and summer drought explained this result. In our study, stand composition had no effect on resilience or resistance for either species. The size effect in oaks was unclear as small oaks displayed either a better performance or a worse performance than large oaks. Small pines displayed better resistance and resilience than pines of a larger size. This work stressed the importance of taking into account stand composition and trees size as well as soil and climatic conditions for each drought events to achieve a better understanding of the diversity of responses to climatic variations among forest ecosystems.