Landscape context outweighs stand properties in shaping saproxylic beetle assemblages on clear-felled stumps

Abstract In managed production forests, dead wood is often deficient, leading to declines in saproxylic (dead wood-dependent) beetles due to a lack of suitable substrates. Tree stumps created after clear-felling can host numerous saproxylic beetles, yet rising demand for renewable biofuels is expected to increase pressure to harvest stumps in the foreseeable future. To minimize biodiversity impacts of stump harvesting, suitable stands and landscapes must be identified. We investigated how saproxylic beetle assemblages on spruce stumps differ between uniform, fast-growing spruce monoculture stands on former arable land and structurally variable stands with longer forest continuity. We also examined whether geographical location or stand type played a larger role in shaping communities. The study was conducted in the boreonemoral forest zone of Sweden. Beetles were sampled by bark sieving from five site pairs, each consisting of one spruce monoculture and one varied stand. Species richness differed significantly among site locations but not between stand types. Community composition was influenced by both stand type and site location, with location explaining three times more variation than stand type. These findings suggest that landscape context may be more important than stand-level properties for structuring saproxylic beetle assemblages on clear-cut spruce stumps. Implications for insect conservation Our study highlights the importance of a landscape-scale perspective when planning stump harvesting, as the effects on saproxylic beetle diversity may vary across the landscape. Developing methods for identifying forest tracts where stump harvesting will have the least impact on species are needed.