More about durable eucalypts for vineyard timber
Paul Millen, New Zealand Tree Grower February 2009.
In recent years the Tree Grower has followed the fortunes of a durable eucalypt project I have been working on. The aim is to have treated pine vineyard posts replaced with New Zealand grown hardwood as young as eight years old.
The New Zealand Dryland Forests Initiative was developed early last year after collaboration from the New Zealand School of Forestry, Proseed, Marlborough Research Centre, Marlborough District Council, Marlborough Lines and my company Vineyard Timbers. We want New Zealand to become a world leader in the breeding and management of elite plantation eucalypts that produce high quality naturally durable wood.
Grant aided research
The Agricultural and Marketing Research and Development Trust gave us $80,000 to establish our first tree breeding trials. We also received another $5,000 from the Neil Barr Farm Forestry Foundation and $260,000 in cash and kind committed by members of the Dryland Forests Initiative.
We plan to plant two highly durable species later this year Eucalyptus bosistoana and E. argopholia. We have also lodged a bid for more funding from the Sustainable Farming Fund to enable future trials on another four species.
The six species were chosen as a result of five years of trials in Marlborough, as well as information from the Eucalyptus Action Group national trials. An Australian project growing eucalypts in drylands since the late 1990s has verified that eight-year-old trees can produce durable posts.
Selecting the best species
Proseed has worked with Forests New South Wales to source 75 families of E. bosistoana and 20 families of E. argopholia. These are now growing at a Marlborough nursery, with the target to produce at least 22,000 seedlings. In the middle of this year the best 18,000 of these will be planted into three replicate trials of 6,000 trees on three separate sites, two in Marlborough and one in north Canterbury.
From these trials we will select the best species in terms of durability, vigour, disease and frost resistance, as well as form. At the same time, we hope to establish plantation management trials to evaluate the production of an intermediate short term crop of durable posts and poles by age 8 to 10.This will be followed in the medium term by coppice-and-standard trials focussed on producing sawn timber by age 15 to 20.
Using eucalypt posts
We have also been working with some local vineyards using eucalypt posts as replacements for broken treated pine posts. Seresin Estate Manager Colin Ross has become an enormous supporter of our project and believes a move away from treated posts is the way of the future for vineyards.Any new post going into Seresin’s olive groves or vineyards now is one of our eucalypt posts.
Marlborough’s 12.5 million vineyard posts are currently dominated by treated pine, which is increasingly a problem. Broken posts are costly to replace and to dispose of as a hazardous waste, so most are either stockpiled on vineyards or taken to landfills. Organic wine and fruit growers need to look beyond the treated posts as organic regulations in the US shun the use of treated posts for new installation or replacement purposes. New Zealand’s organic exports to the US are $40 million.
There is also a hefty carbon cost for vineyards using treated posts, which have to be trucked to a central location to be treated. Wine companies trying to project a sustainable image to the world could make a huge carbon saving by using untreated eucalypt grown and milled near vineyards. In the longer term, the eucalypt plantations could be used for cross arms on power poles, railway sleepers, building poles, other agricultural poles and timber.
This is not the first initiative to get a durable eucalypt industry in the ground in New Zealand. However we think that the timing in a market focussed on sustainability, the need for a treated pine replacement and the collaborative effort and commitment by groups will give this one the momentum to be successful.
We plan to have our project website established this month, but until then anyone wanting more information can contact me at p.millen@xtra.co.nz.