"Clearly treated wood posts are still the most preferred and cost effective cultivation solution in the national and international vineyard industry," - Denise Conradie
Vineyard posts, or vineyard poles as they are known locally are wooden poles used in the growing of grapes used in the production of wine, are part of the R&B Group product mix.
Wood has been used in South Africa since the early 1900's and generally, both nationally and internationally, wood vineyard posts still dominate in the wine industry. Alternatives to treated timber for this application have not made significant inroads.
The disadvantages of using non-wood posts such as steel, concrete and composite trellising systems vary from damage to mechanical harvesters and lower load bearing capacity and failures such as bending due to prolonged high temperatures. The conclusion is that when a life cycle assessment of vineyard posts is followed to draw comparisons between alternative products, preserved wood holds its own if not out performs some of the other products.
Importantly, from an environmental perspective, wood has a low carbon footprint. Carbon dioxide is stored throughout the life of a wood product, ensuring the gas is sequestered from the atmosphere. Forests are thus highly efficient 'carbon sinks' while also being producers of oxygen.
The most sound treatment method for preserving timber to extend the life-time of the wood is still the pressure treatment of wood in a pressure vessel. During this procedure a vacuum is drawn to remove as much air as possible from the timber cells and then pressure is applied to ensure that the preservative is pushed as deep as possible into the cell's lumen.