At Orup in Skåne, Sweden, SoilCare tested whether loosening a naturally compacted subsoil could improve rooting and yields. The site is a silty sand with high subsoil bulk density and roots seldom below 30 cm. The trial compared three treatments implemented once in autumn 2018: standard practice, subsoiling to the upper subsoil, and subsoiling with straw pellets injected into the 24 to 35 cm layer. A randomized block design with four replicates and 6 × 20 m plots was used. Winter wheat grew in 2019 and sugar beet in 2020. Measurements covered the volume of subsoil affected, root counts by depth, penetration resistance with a 2.5 MPa root-limiting threshold, bulk density and coarse fragments, soil C, N and pH in top- and subsoil, and yields.

Mechanical loosening created distinct subsoil rows. Only 38 to 45 percent of the upper subsoil volume was affected. Straw pellets settled at the bottom of loosened rows rather than mixing. Even so, rooting improved. Maximum rooting depth reached about 35 cm with subsoiling plus straw, compared to about 27 cm in the control. Penetration into the compacted layer increased from roughly 4 cm in the control to about 11 cm with loosening treatments. Despite better rooting, grain and beet yields did not differ significantly at whole-plot scale over two seasons. When results were adjusted for the fraction of subsoil actually affected by the strips, relative yields increased compared to the control.

Stakeholders judged the approach plausible and were interested in learning more, but highlighted barriers. Injecting large amounts of organic material is technically demanding and costly. Advisory capacity and subsidy flexibility matter for adoption. The short-term conclusion is pragmatic. Subsoiling, with or without straw pellets, improved rooting in a naturally compacted subsoil but did not deliver short-term yield gains. Longer-term, repeated treatments, alternative organic materials and multi-site testing are needed to understand agronomic and hydrological benefits.