grapegrowing
Trellising & Posts
Disposing of treated timber posts Tackling a thorny issue for the winegrowing sector Timber posts used to line vineyards the country over, providing necessary support to vine rows in rain and shine. The grim reality of these posts came, however, when it was time to replace them once they degraded. Harrison Davies spoke to those involved in efforts to find the posts a place to rest.
W
ooden posts were once a go to for viticulturists looking for an easy material to line their vineyards with.
Senior RD&E program manager at Wine Australia, Alex Sas, said there was space for a new approach for disposing of the old posts.
The issue with timber is that it’s an organic material and can degrade due to factors such as weather, pests and general decay.
“We need to know the approximate volume and condition of posts so that we can work with these businesses to develop regionally-specific options for growers looking to dispose or repurpose old posts,” he said.
The solution way back in the 1930s was to treat the timber with a variety of minerals, most commonly arsenic and copper – a substance known as CCA. The substance was widely used and resulted in the commonly seen green tinged wooden posts that population the viticultural landscape. However the posts were found to be potentially toxic to people and produce in their vicinity. Wine Australia is currently conducting a survey to find where the treated timber posts are located and what producers have done with them. 40
Grapegrower & Winemaker
The use of CCA treatment went more or less un-noticed for decades until 2005 when the Australian Pesticides and Veterinary Medicines Authority (APVMA) released a report into its effects on people. The report laid out several suggestions for its removal, including its removal from children’s play equipment and also advocated for their removal from vineyards. While the research suggested the posts would not leach chemicals to the fruit themselves, there was evidence that www.winetitles.com.au
AT A GLANCE As an organic matter, timber posts degrade from weather, pests and general decay • CCA was created in the 1930s to treat timber posts to improve their lifespan • The use of CCA-treated posts in vineyards went largely unnoticed for decades • Some research suggests chemicals from treated posts could leach into surrounding ground • The disposal of treated posts remains a challenge • Growers have been warned not to burn treated posts • Used treated posts should be disposed of at an accredited waste facility • Potential health implications have led many growers to adopt posts made from materials like steel or plastic
July 2022 – Issue 702
