Sustainable vine training
GRAPE growers in Australia began training their vines along rope, attached to bush timber posts.
Generations later they moved onto treated CCA timber and some now use steel.
More recently an Australian company has patented a new look, utilising untreated timber covered with recycled polymer.
Not only does the company promise a stronger more flexible post, they have also been issued Aus-Organic certification.
Woodshield sales manager Ashley Davidson said the post’s inner core is timber, while the outer layer is recycled polymer, up to 6mm thick.
The polymer provides a protective layer for the timber, completely encasing it, and removing the need for the timber to be treated chemically.
The polymer protection also provides the timber with more flexibility, longevity and strength.
Davidson says the idea came from a group of passionate wine drinkers, who just happened to be involved in the plastics industry.
They wanted to solve the ongoing problem of broken treat trellis posts and the sustainable polymer coated timber post was born.
“We can go right from taking a dripper tube/irrigation off a vineyard, recycle it and put it back out on a post.
“Then in 50-plus years, the tested life span of the polymer, you can strip it, chop it up and recycle the plastic again.
“The wood can be mulched, chipped or turned into firewood, because it is non-treated, no chemicals to worry about.”
“Each end has a cap and the recycled polymer is extruded over both the cap and the timber post completely sealing it, ensuring the posts don’t absorb moisture that could cause rotting.”
He said the caps provide strength to the end of the post, meaning they can still be hydraulically forced into the ground – without fear of damage.
Sold in a variety of lengths, from 1.5 metres up to 4.8 metres, and four different profiles, the posts are advertised as being 40 to 50 per cent stronger than the bare timber alternative.
It is the plastic extrusion that provides that strength.
“Any pressure that comes on is distributed up and down the fibres inside.
“Whereas if you have a standard treated CCA post, with say a knot in it, when pressure is exerted down the post and reaches the knot, it will snap or crack.
“The polymer outer layer allows the pressure to move up and down the fibres, without causing damage.”
Davidson said no specialised equipment is required when installing the posts or wires, and despite having to puncture the plastic outer covering for clips and fasteners, there isn’t an issue with moisture getting into the inner timber.
“The plastic just closes around any break caused by nailing through it, that’s the nature of the beast.
“You can hammer it, nail or screw it.
“It’s what people know, in terms of a timber post, it’s just more sustainable.”
The patented system is being used by the wine industry, the oyster industry, the equine industry and the company is exporting posts to New Zealand, Japan, USA and Europe.
NEW ERA: Australian company Woodshield has patented a new untreated timber covered with recycled polymer for vine growers.