The issue of smoke taint in wine grapes as been fraught for both land managers and the wine industry since around 2004 when research conclusively proved that smoky flavours in wine were directly attributable to bush fire smoke.
The issue has been particularly prevalent around the Pemberton area, where prescribed burns occur far later in the grape growing season than would typically occur in Margaret River or the Great Southern – forest fuels on Pemberton’s rich moist karri loams are generally not dry enough to burn until around January or February when post-veraison grapes are at their most vulnerable to absorbing smoke compounds.
A pro-active approach from Wines of Western Australia, regional wine associations, the Department of Primary Industries and Regional Development (DPIRD) and the Department of Biodiversity, Conservation and Attractions Parks and Wildlife Service has been successful in creating processes to mitigate vineyard risks resulting from prescribed burns. The processes involve collaboration and information exchange between the government agencies, stakeholders and the local shires, local fire brigades, and vineyard owners.
A recent prescribed burn around the Pemberton townsite which covered a large area of high fuel forest area, and bordered several local vineyards, was a case which highlighted that these processes are working. The Parks and Wildlife Service prescribed burn was undertaken in 20 year old forest fuel, and was completed successfully with no negative impact on neighbouring vineyards. It was conducted through extensive planning and discussion between the Parks and Wildlife Service and the Pemberton Wine Region Association.
President of the Association Ash Lewkowsky, said that the level of collaboration and consultation the department had with the wine industry in conducting the prescribed burn had been outstanding.
“We have now been invited to be part of the department’s planning process for the 2018/19 and 2019/20 prescribed burn program. We are really pleased to be part of the team effort to ensure the best outcomes for both our industry and the protection of the community,” he said.
The first step of the process involved Parks and Wildlife Service releasing its one and three year programs of prescribed burns maps to both the State and regional wine associations. Regions via their associations are then able to comment on the plan, identifying windows of opportunity and potential issues.
The regions in turn communicate with local fire officers to update on ripening progress and anticipated harvest dates, while Parks and Wildlife Service constantly monitors conditions for burning against potential impacts on the community and vineyards.
As vintage progresses, the regions update Parks and Wildlife Service on areas available for burning as grapes are harvested.
Regions also work with the local shires and bushfire brigades to advise them of the impact of other factors such as landholders conducting burns on private property.
Impact assessment is supported by use of up to date vineyard maps obtained through satellite imaging and subsequent ground truthing by field officers. The maps have been developed by DPIRD, which has also developed a Smoke Taint Risk Calculator. This online tool calculates the percentage risk for any given vineyard based on temperature, climate and historic weather data. DPIRD can also run diagnostic tests to assess smoke compounds in the berries prior to harvest to help winemakers decide whether or not to make wine batches from those vineyards.
Prescribed burns are set to increase across the South West over the next few years in an effort to minimise the impacts of bushfires on local communities. Prescribed burning by the Parks and Wildlife Service has increased in recent years after a variety of factors had led to reduced programs over the previous decade. This in turn has resulted in a greater fuel load in some areas which will be further targeted in the prescribed burn program in 2018/2019 and future years.
Vineyard owners or managers who would like more information on prescribed burns and when they are taking place are encouraged get in touch in the first instance through their regional associations. Listed below.
Contact details as follows:
Department of Biosecurity, Conservation and Attractions:
Department of Primary Industries and Regional Development:Glynn Ward
Wines of Western Australia: email@example.com
The Swan Valley Winemakers Association: firstname.lastname@example.org
Perth Hills Wine Region: email@example.com
Peel Wine Association: firstname.lastname@example.org
Geographe Wine Association: email@example.com
Margaret River Wine: firstname.lastname@example.org
Blackwood Valley Wine Industry Association: email@example.com
Pemberton Wine Region Association: firstname.lastname@example.org
Great Southern Wine Producers Association: email@example.com