Agroscope, Institute for Plant Production Sciences IPS, 1260 Nyon, Switzerland

Natural revegetation of set aside fields on fertile arable soils

Two set-aside plots were established by natural revegetation and by sowing a wildflower seed mixture at each of 13 sites on fertile arable soils of the Swiss plateau.<br>The objectives were to investigate whether species rich plant communities would develop on naturally revegetated fertile arable soils and whether problem weeds such as Cirsium arvense and Rumex obtusifolius, would be more abundant in naturally revegetated plots compared to sown set-aside plots. Within the three years of study no red data book species could be found in naturally revegetated plots, and plant species diversity was always significantly lower than in plots sown with a wildflower mixture.<br>In addition, cover of problem weeds and grass cover in plots under natural revegetation were higher, and herb cover lower than in the sown plots. However, the number of unsown species establishing on the sown plots was significantly reduced in comparison with the unsown plots.

To the archive