MIXING SUGAR WITH WINE-AN APPROACH TO SOIL QUALITY BENCHMARKING

THERE HAS BEEN much recent discussion about ‘soil health’ in Australian agriculture; the sugar industry is no exception. However, much of this discussion is characterised by uncertainty as to what soil health is, how it might be measured and how growers might enhance it. This paper discusses a project that was recently conducted to assist the Australian wine industry navigate these questions, with the intent of offering perspectives that are useful to the sugar industry. Through a combined workshop and literature review process, a minimum dataset of key soil properties was identified to assist in soil quality assessment in the wine sector. An important part of this was to move away from the concept of ‘soil health’ and instead focus on ‘soil quality’ on the basis that the latter term is more closely aligned with the ‘fitness for purpose’ of a soil for wine grape (or sugarcane) production. Soil sampling was then conducted in 5 wine growing regions to illustrate how this minimum dataset could inform assessment of soil quality at the regional scale and the possible need for remedial action. With repeat sampling every few years, the data collected through a program such as this will promote assessment of soil change over time, and therefore of the possible need for specific actions aimed at maintaining or enhancing soil quality. For both of these purposes, a program of soil sampling and analysis could readily be coordinated in the sugar industry by local Productivity Service Companies or consultant agronomists, perhaps in partnership with providers of soil testing services, to generate and maintain a database of the regional distribution of properties relating to soil quality and associated threshold values. In this way, a local basis for maintaining the quality of sugarcane soils and demonstrating the sustainability of cane growing practices could be established. We illustrate this here using the McLaren Vale grape growing region as an example.