Location

Askov Experimental Station

Starting year

The Askov long-term straw disposal and cover cropping experiment was initiated in 1981 and terminated in spring 2020 and subsequently converted to semi-natural grassland.

Short description

In the arable phase (1981-2020), varying amounts of straw incorporation (0, 4, 8, 12 t/ha/year) and +/- ryegrass as cover crop in a spring barley monoculture were investigated. In the semi-natural grassland phase (2020-onwards), all plots were converted and grass receives no fertilizer and the biomass is cut once a year in August and left on the plots. The unique setup makes it possible to investigate changes in soil properties following introduction of grassland on soil with contrasting initial conditions due to different long-term management history, and without confounding effects of differences in soil texture and climate.   

Soil type(s)

Askov: Sandy loam, Aric Haplic Luvisol, Ultic Hapludalf. 

• All treatments refer to the arable phase of the long-term experiment (1981-2020):
• Straw incorporation rate is the main-plot factor: 0, 4, 8 and 12 Mg/ha/yr.
• Cover crop is sub-plot factor: Without cover crop, ryegrass and grass-clover cover crop, respectively.
• Plouging time is strip-plot factor: Ploughing in spring or autumn.  

Sample archive

Crop yield in the arable phase is available. Soil samples are available in the archive and taken every second year, air-dried, 2-mm sieved and archived.