Different Aspects of the Utilization of a Subsoiler equipped with an Horizontal Device for Soil Disruption

Abstract

Subsoiling is a very efficient tilling method for reducing soil compaction caused by repeated passages of agricultural equipment in orchard's rows. Soil compaction can restrict the passage of water in deep layers and cause excessive surface water stagnation. Subsoiling can restore the structure of compacted soils through a vertical cut and an elevation of the ground, without mixing the tilled layers. Consequently, stable soil porosity and better drainage are favoured, the plough sole is removed, altogether improving the growth of roots and the absorption of nutrients. In particular, vibrating subsoilers can reduce the high draft force required by common subsoilers, and consequently smaller power class tractors can be employed. In order to assess several aspects regarding the use of a single shank subsoiler with an innovative oscillating device, the CRA-ING carried out specific tillage tests. The oscillating device is an horizontal metal plate that, during its run along the drill horizon, is raised at regular intervals through a connecting rod driven by a crank mechanism, consequently moving a greater mass of the above soil. Such a subsoiler has been tested under typical operating conditions in order to investigate different aspects of its utilization such as the energy requirements, the quality of the tilled soil and the level of vibrations transmitted at the driver seat by the oscillating device (according to the ISO 2631-1:1997 standard). Two series of tests have been performed through the untilled rows of a fifteen years old poplar grove, using the subsoiler both with the oscillating device and as a traditional one, at the same forward speed, with the aim of comparing the observed results. The tillage was done at the maximum depth depending on the soil's workability conditions (0,45 m), using a 110 kW, 4WD tractor.