Abstract
As New Zealand's traditional sheep and beef farms are being increasingly converted to dairying it is important the soil does not become degraded and consequently unproductive. It is necessary to establish the effect dairy cattle treading is having on soil properties. This study set out to determine how much of an effect cattle treading is having on the soil, and to see if this effect varied locally. This was done through comparing untreaded areas under the fenceline to within paddock treaded areas. Samples were taken from Mottled Fragic Pallic Soil underneath a dairy farm in Clydevale, South Otago to determine bulk density, gravimetric and volumetric water contents, macroporosity, total porosity and field measurements of penetration resistance.
Bulk density and gravimetric water content were the properties most affected by treading. Bulk density medians increased from 0.92 Mg m⁻³ in the untreaded areas to 1.05 Mg m⁻³ in the treaded areas (p = 0.0052) and gravimetric water content medians decreased from 56.2 % to 43.9 % (p = 0.0366). Significant changes in the level of compaction between paddocks were seen more through the comparison of the treaded and untreaded areas than by just comparing the treaded areas to each other.
These findings are in line with other research on cattle treading as they show the soil properties to be influenced by treading, thus indicating soil compaction is taking place. The level of soil compaction varies on a local scale, and thus demonstrates the importance farm management plays in controlling soil compaction.