This dataset includes the 1627 trees sampled for herbivory damage. For each focal tree sampled, we extracted the list of neighboring trees. We used euclidian distance between focal and neighbour trees, calculated with Arcgis software and ArcToolbox option. The aim of this dataset is to work on the tree diversity effects at a neighbour scale.

For the list of focal trees, we selected at random 3 individuals per species per plot in mixture among the 6 biggest DBH and 6 trees in monocultures among the 12 biggest DBH. Some plots have more trees sampled. For each tree, the CrownCrossSectionalArea (from dataset "Plot descriptors - tree data") was used to calculate a radius and we used tree coordinates as centre. A circle was drawn for each tree to represent the tree crown. A tree is considered as neighbour if its crown is at a distance of less than 3 meters from the crown of focal tree. Each stem is considered as an individual. Dead trees are eliminated. Focal trees were also sampled for pathogens damage assessment, Carbon and Nitrogen element analyses, stable isotope composition, and chlorophyll fluorescence.

Exploratory sites from Italy, Germany, Finland, Spain, Romania, Poland

Focal tree species are : Abies alba, Acer pseudoplatanus, Betula pendula, Carpinus betulus, Castanea sativa, Fagus sylvatica, Fraxinus excelsior, Ostrya carpinifolia, Picea abies, Pinus nigra, Pinus sylvestris, Quercus cerris, Quercus faginea, Quercus ilex, Quercus petraea, Quercus robur, Quercus rubra

With this dataset, it is possible to work at a subplot level and calculate diversity indices, tree apparency… However, information about neighbours is incomplete for focal trees close to the plot border. Therefore, the distance of the focal tree to the border is mentionned.