Phase 2: Responding phase
On 12-16 June 2017, the vegetation was removed from all subplots within each plot using a sod-cutting machine (IB300, IBEA, Tradate, Italy) (De Long et al. 2019). All sods were cut to a standard depth of 3 cm. This was done to remove most of the thicker roots (and prevent re-growth in the responding plant community), while also allowing us to retrieve most of the remaining sandy soil from the sods. On 20 June 2017, each subplot was sown with the 24 species that were used in the conditioning phase and that occur at the site (Bezemer, personal observation). In addition, 10 response species that occur in the area were included to be used for other work beyond the scope of this study (Table S1). Plots were watered regularly in the first month to assist establishment of the germinating seedlings. Plots were left to develop naturally and disturbance was minimalized during sampling events.