Study Site Trials

The SICS selected for trialling in this Study Site are described below: 

Country General Treatment Category Study Site Trials
Sweden Sub soil loosening, tillage

1. Sub soil loosening - Sub soiling loosening; Sub soiling loosening with straw pellets; Normal mouldboard ploughing - control

Study Site poster 2018 (download)


 SICS 1:  Sub-soil loosening with straw pellets


 Subsoiler2400x300  Trialestablishment400x533    Sweden amendment  


 Key findings

  • Subsoiling affected only a few centimeters of the upper subsoil layer below the topsoil
  • There were distinct stripes in the subsoil but 38-45% of the upper subsoil layer was affected • Straw incorporation during subsoiling did not result in mixing with loosened subsoil
  • Rooting characteristics were improved by subsoiling
  • The impact of subsoiling on yields of cereals and sugar beets was not significant. However, considering that only subsoil stripes may affect yields, recalculations indicated a positive impact of stripes on yields


Geographical description

The Orup site is located in the county Skåne in Southern Sweden. Precipitation varies between 500 and 1000 mm per year. Mean temperature is around 0 °C in January and 16 °C in July.  On the site, the subsoil is compacted (density between 1.7 and 1.9 kg L-1). The soil is a silty sand and the compaction is most likely from the time the ground was formed, has a natural origin. The harvests for this site have remained much lower than at the other soil fertility experiments, approx. 30-40% lower.  In spring 2011, an inventory was made in Orup with regard to root growth in the subsoil. The results show the same results as in previous studies in the 1990s: the roots of the crop are restricted to the topsoil and no roots grow below 30 cm depth. A structural improvement through liming is limited at Orup due to a low clay content (about 10%).  In lighter soils such as this, a structural improvement can be achieved primarily through the supply of organic matter. Therefore, the experiment investigates the possibility of improving soil structure through the supply of organic material in combination with mechanical subsoil loosening. The supply of organic material is made in the form of straw pellets that are blown into the ground.

Cropping systems

Different cropping intensities from no fertilization to high fertilization rates are applied at the Orup site. Both treatments with and without animal manure are run. Rates of manure are in relation to yields provided by the cropping system. The site is treated according to conventional agricultural practices of the region.

 The map of Skåne showing the Orup study site


Types of crops
Two 4-year rotations are applied:
- crop rotation with livestock: barley, ley, winter wheat and sugar beets
- crop rotation without livestock: barley, oil seed rape, winter wheat and sugar beet.

Management of soil, water, nutrients and pests
Soil tillage includes yearly mouldboard ploughing, cultivation, fertilization, manuring, chemical weed and pest treatment. Crops are rain-fed and no catch crops to combat N leaching are grown.

Soil improving cropping system and techniques currently used
Measures include crop rotation, use of animal manure, no removal of crop residues in non-manured plots, and
regular lime application.