2.3. Yield and plant species composition
The botanical composition was determined in 2018 with the use of a quadrat frame that was subdivided into smaller areas (Cayley and Bird, 1996). The frame, which had a size of 0.25 m2 (0.5 × 0.5 m) and a grid of 0.1 × 0.1 m, was randomly positioned within the plot. In each quadrat, the species were recorded, and the results were expressed as the percentage frequency.
The aboveground biomass was harvested three times per year in May, June and August in the period from 2014‑2018. The dry matter (DM) of the yield was determined by harvesting the plants from the whole surface of the plot and drying them at 70 °C to a constant weight.