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Long term experimental plot

Department of Bioscience, Silkeborg, is running an experimental field plot on Djursland, the so called Kalø experimental plot.

Airphoto of the experimental area, spring 2006.

The experiment was set up to investigate the combined effect of low doses of pesticide and nitrogen on grassland communities.

The experiment was established in 2001. Before sowing, the area was deep ploughed down to 60 cm. Thirty-one species were sown in spring 2001. The species selected were grassland species covering different life form strategies (CRS strategies sensu Grime).

Experimental manipulations

The experimental manipulations are set up as a complete randomized block design with 10 replicates of each of the twelve treatments including four glyphosate treatments (0; 14.4; 72 and 360 g a.i./ha equal to 0, 1, 5 and 25% of label rate of 1440 g glyphosate/ha) and three nitrogen treatments (0, 25 and 100 kg N/ha). All plots receive phosphorus (53 kg/ha), potassium (141 kg/ha), sulphur (50 kg/ha and copper (0.7 kg/ha) every year. The RoundupBio® formulation of glyphosate is used for the experiment.

For the herbicide applications, spraying equipment for experimental applications is used. The beam is 3 m with 0.5 m between the nozzles (Lurmark Lo-drift LD 015 Green nozzles with a pressure of 2.0 bars). Fertilizers are spread by hand. The plots were treated by glyphosate for the first time on 24. August, 2001. Since then, it has been treated with herbicide and fertilizer once every year in spring (mid-ultimo May).