Biodiversity Among the Vines
While agricultural greenhouse gas emissions pricing has the longevity of farming sheep hotly debated in the efforts to meet our carbon targets, one Canterbury vineyard is using the animal New Zealand’s economy was built on to achieve their net carbonzero certification.
The 20th Century’s industrial revolution saw the replacement of horses for more powerful combustion engine tractors. Its nod of thanks was the unit of measure ‘horsepower’ – a reference to the rate at which work is done to produce as much as possible from the land. The first half of the 21st century however has seen the reference to success in farming and growing food and fibre moving from the ‘output’ to ‘outcome’ of the food production on the environment and society as a whole.
This was one important focus for Greystone Wines (North Canterbury) in achieving their Toitū Envirocare net carbonzero certification as part of bold plans to reduce their environmental impact. They have undertaken an emission inventory across the entire company, including travel, how much diesel and petrol they use and measures to counter that.
They have seen a 50 per cent reduction in their tractor use among their vines by integrating sheep grazing to do the work. ‘We drive our tractors through these vineyard rows nearly 30 times a year – that’s 200 km every time,’ explains Greystone viticulturist Mike Saunders.
Greystone company cars are now hybrid, its new Fendt tractors are 50 per cent more fuel-efficient and only carbonzero electricity is used in their strawbale winery. Even the glass bottles have been switched to lighter-weight options across their production.
Most of us agree that the move to reduce fossil fuel use is heading in the right direction, but to replace it with methane emissions from sheep may raise a hard-core urban greenie’s eyebrow. ‘By having sheep grazing we are cutting down compaction of the soil that the tractor passes cause,’ explains Mike.
Compaction is one of the many things Greystone Wines wants to avoid to have healthy, functioning nutrient cycling for their vines. Vines require a lot of water and nutrients to produce an abundance of fruit, however Greystone are using the magic of plants to do the job of fixing nitrogen from the atmosphere as a natural fertiliser and irrigation usage is being decreased by maintaining ground cover which holds the moisture in the soil.
But wouldn’t the sheep eat the grapes? The vineyard team have retrained a trial block to a high-wire system where they can now run sheep in the vineyard every day of the year as well as the resident Pekin ducks living on-site to eat the grass grubs.
‘The sheep are grazing on a mix of 16 species, including sunflowers, oats, lentils and beans in between the rows of vines. By retaining living cover crop roots we can sequester, transfer and store carbon between plant and soil,’ continues Mike.
The adoption of these regenerative viticulture practices involves the team looking at every inch of the 50-hectare farm and vineyard for ways to increase biodiversity by working with nature, rather than against it. And what better way to return to a previous land-use of sheep farming integrated with wine.
‘My mum talked me out of farming as it wasn’t a sexy industry, so I did my degree at Lincoln in Horticulture despite loving the sheep on my grandparents’ farm at Leeston. I get to be a sheep farmer among the vines,’ he explains.
Greystone rotationally graze three mobs of 200 every 24 hours when leaf plucking and they lamb 2,000 of the neighbours’ Corriedale ewes which helps them also diversify their income.
While many oppose regenerative farming, saying the practice leads to a decrease in yield, Mike works off a different metric of success where the net return per tonne is higher due to a reduction of inputs. ‘High-production vineyards were never designed on the right rootstock to handle a rapid change in management by searching deep for water and nutrients so they rely on high water, chemical and fertiliser regimes. We’re retraining our current rootstocks to grow deeper by watering less often, but for longer periods to build long-term resilience and improve our nutrient cycling with home-made compost. The sheep have decreased our reliance on labour and they are redeployed into higher value tasks.’
And the irony is the hero of this story is set to be taxed for burping. All without taking into account when used in an integrated farming system they can reduce a reliance on fossil fuel, migrant workers, agricultural chemicals and water use, while improving biodiversity, soil health and worker wellbeing.
