*2.1. Study Area*

The study was carried out in Damak forest (48◦31' N, 20◦82' E), in the county of Borsod-Abaúj-Zemplén, Hungary (Figure 1). The area is characterised by a temperate continental climate. The mean annual temperature of the area is 9.5 ◦C; warmest period ranges from May to September (20.0 ◦C in July). Maximum precipitation within this warm period is 82 mm (July); mean annual precipitation is 567 mm. Forest typology is classified as mixed broadleaf and coniferous woodland (Figure 2). Dominant species are Hungarian oak, common nettle *Urtica dioica* L., black locust *Robinia pseudoacacia* L., Scots pine *Pinus sylvestris* L. and hornbeam *Carpinus betulus* L.

Soils in the studied area are of the Haplic Luvisol type [27,28]. This is a non-calcareous soil, with neutral pH and high in organic matter. In stark contrast to the Hungarian Plains (80 km South-West, higher precipitation and lower temperatures in Damak forest has led to the development of this soil type. As this is a forest soil, there is an organic horizon, comprised primarily of leafy material that is separated from the mineral horizon [27]. For this study, we identified a Haplic Luvisol that to our knowledge was negligibly affected by human disturbance, at about 250 m from the experimental site. In Damak Forest, where soil samples were collected, there have been no recent significant disturbances that could affect this study, in particular prescribed or wild fires.

**Figure 1.** Study area: Damak Forest (red point; geographical coordinates 48◦31' N, 20◦82' E) in Borsod-Abaúj-Zemplén county, Hungary. Inset map: Hungary (red) in Europe.

**Figure 2.** Characteristic vegetation and strata in Damak forest: (**a**) soil to litter layer interface, (**b**) litter layer, (**c**) understorey and (**d**) overstorey. Photo: Jack M. Bridges.
