Dataset for ×Sorbaronia ʹMitschuriniiʹ – an overlooked alien shrub rapidly expands in temperate Scots pine forests (10.1093/forestry/cpad058)

Data from assessment of invasive ×Sorbaronia ʹMitschuriniiʹ assessment (doi: 10.1093/forestry/cpad058). We aimed to characterize the unique phenomenon of ×Sorbaronia ʹMitschuriniiʹ spread into temperate Scots pine forests. We assessed the surroundings of anits abandoned ×Sorbaronia ʹMitschuriniiʹ plantation, established in 1986 near Ośno Lubuskie (W Poland). Around the plantation we established 66 study plots in 30 m intervals along eight transects, in a systematic design. Using generalized linear mixed-effects models we analyzed how the distance from the propagule source (i.e. abandonded plantation), maximum age of ×Sorbaronia shrubs assessed using dendrochronological techniquesage of ×Sorbaronia shrubs, and light availability determined the density and biomass of the studied plant. We found that its mean aboveground biomass in the plantation was 7.22±0.66 Mg ha-1, and decreased with a distance from the propagule source: 6.83 Mg ha-1 30 m from the abandoned plantation, 1.38 Mg ha-1 at a distance of 90 m, and 0.11 Mg ha-1 at a distance of 180 m, almost disappearing at further distances (but present at the maximum distance of 450 m). The density and aboveground biomass of ×Sorbaronia ʹMitschuriniiʹ increased with increasing maximal age of the studied plant and its light availability. The ×Sorbaronia ʹMitschuriniiʹ plantation of the studied taxon acted as a strong propagule source, as it reached a density of 100 ind. 100 m-2 after five years, forming a dense shrub layer, capable of reproducing,