March (No. 494)
Compaction a heavy weight on vineyard soils
Anita Donaldson and Chris Saunders
Researchers at the University of South Australia, Agricultural Machinery Research and Design Centre, (AMRDC) currently being led by Dr Chris Saunders, are seekings ways to assist grapegrowers with practical management of vineyard machinery and equipment, to lessen the impact of natural or traffic-induced subsoil compaction in vineyard soils.
The four-year project has included several experiments investigating ripper technology and capacity on subsoil and vine response, and also the influence of timing for when vineyard inter-row traffic strategies are best performed. Current project emphasis is towards including the application of liquid ameliorants to the subsoil during the loosening operation to assist with chemical inbalance and reduce its effect on compaction.
In the January 2005 issue of Grapegrower & Winemaker, David McKenzie of Precision Land Management in Orange, New South Wales, wrote of soil-related problems in vineyards. These included problems:
- created during vineyard development (compaction induced by heavy machinery and ripping when the soil is too wet)
- induced by vineyard management (post-development), including compaction created by routine vineyard operations.
McKenzie wrote that compaction is a problem often overlooked. “The problem of wheel compaction in vineyards tends to be most pronounced where rock occurs within about 60cm of the soil surface. This connection of the columns of compacted soil with underlying hard layers tends to trap the roots in what is analogous to a flower pot without drainage holes. A combination of over-watering and heavy rain can cause waterlogging problems in this constrained zone. Waterlogging and the production of high-quality wine, of course, are totally incompatible (Bemusca 2001).
“If the soil has good structure to a depth greater than about 80cm, the vine roots tend to grow under the compacted wheel tracks and into the inter-row area.
“In areas with shallow root zones and near-vine-row compaction problems, serious consideration should be given to over-the-trellis equipment that has wheels in the middle of the inter-row. Modern grape harvesters have this configuration, so it may also be possible to carry out operations, such as spraying, from these gantry-like machines,” (McKenzie, 2005).
The GWRDC-funded project at the University of South Australia has been co-funded by the State Energy Research and Advisory Committee (SENRAC) and UniSA, and supported by Orlando Wyndham, Kubpower, DeMill Engineering and Dr Jeanette Chapman.
With the above collaborators and funding, UniSA has designed, manufactured and is now testing a vibratory ripper, which it hopes will provide two major benefits. First, to allow growers to carry out a deep-ripping operation with existing vineyard tractors to a depth greater than that currently achievable, where necessary, and second to be more efficient than conventional deep loosening in terms of fuel and power usage.
NOTE: The complete article can be found in the March issue of The Australian & New Zealand Grapegrower & Winemaker.