Swedish experiments on subsoil compaction by vehicles with high axle load

Abstract. Soil and crop responses to traffic with vehicles having an axle load of 10 tonnes were studied in 9 field experiments. The clay content of the soils ranged from 6 to 85%. The traffic resulted in increased soil bulk density and strength to a depth of 50 cm. Compaction effects persisted below plough depth 7–8 years after traffic. Crop response was negative and increased with clay content of the soil and with traffic intensity and decreased with time. The results indicate that maximum axle loads on arable fields should be less than 10 tonnes, especially on clay soils.