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restricted by moisture stress. So long as the stress is a managed stress – not excessive – it allows photosynthesis to continue but without shoot growth. Vines in this state direct all sugars produced by the leaves to the fruit, which appears to enhance quality-related pathways in the grapes. “The story is not about final Baume. It’s more about the accumulation of sugars during the critical period of veraison or colour change. Vines with a high carbohydrate status will produce better quality fruit during their earliest stages of ripening. You tend to lose those favoured characters as you head more into drier, high stress conditions. Central Otago, for example, has much greater capacity to stress its vineyards than is commonly associated with Burgundy. The number of days and hours that a vineyard is under high moisture stress has a big impact on the flavour and tannin profiles of the fruit that it produces. That’s where the New Zealand region gets its big, dense Pinots.” Dr Pirie related some convincing arguments for returning to the Pipers Brook district. But having a sound theoretical rationale is no substitute for cost-effective, well-directed, on-ground management practices, outstanding grape and wine quality, and consistently reliable vineyard data. Apogee has all of those in abundance. While Pirie’s vine choices and management strategies were still being planned, he made sure his site was equipped to benefit from every skerrick of relevant data he could collect. A vineyard weather station and wireless substation measure and record canopy temperature; solar radiation and UV levels; relative humidity; leaf wetness; wind speed and wind direction. Soil moisture is monitored at depths of 200mm, 400mm, 600mm and 800mm. Derived measures of wind chill, soil moisture tension and evapotranspiration produce additional figures. “I’m able to collect and analyse data recorded every five minutes during the entire growing season,” Pirie explained. “We have whole sets of it stretching back over four years now. In addition to helping us guide our current management practices, they offer opportunities for us to go back to our records to see if we can define some of the critical moments that occur on the site.” Apogee’s long list of innovations is not limited to data collection and interpretation. A radical trellis design is being used to address potential issues of crop load and vine yield. Dr Pirie refers to it as a modified or unilateral Scott Henry system. Its dimensions are outwardly
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Dr Andrew Pirie at Apogee Vineyard, at Lebrina, in north-east Tasmania. similar to those found on other Tasmanian sites: 2.2m row spacings with 1.3m between vines. Instead of following a conventional Scott Henry double layered pruning system – with pairs of canes extending either side of the vine’s central trunk – Pirie’s design consists of just one pair of arms, each pointing south. These unilateral arms are then treated in the traditional Scott Henry manner, with shoots on the lower arm being trained downwards and those above being trained upwards. A ventilation window between the two arms – almost large enough for a person to climb through – allows enhanced air movement and, thus, increased protection in the face of the district’s main disease risks of botrytis bunch rot and powdery mildew. Vineyard spray regimes couldn’t be simpler. They are a matter of hitching a humble Mahindra tractor to a very basic spray rig that does the job without fan assistance. Harking back to times spent walking through the great vineyards of Champagne and Burgundy, Pirie says he is replicating the traditional French practice of leaving a significant gap between one vine and the next. The result is an intensive hybrid form of management where Old World meets New World. “Rather than filling the wire – as we’d be doing according to Australian winegrowing practices – we’re following the French Guyot system of leaving a space of about 30-40cm between successive canes. That allows better sunlight penetration early on in the growing season, the critical period when bunches are being formed for the following season. The outcome is improved bud initiation and bud fruitfulness. W i n e & V i t i c ult ur e Jo ur na l SEPTEMBER/O C TO BER 2013
“This unilateral system really turbocharges our viticulture. The lowest vineyard yields we’ve experienced here over the last four years have been for our sparkling rosé – which gets the best of the Pinot Noir – and they’ve been around 12-14t/ha. Our average vineyard yields have been 14-16t/ha. That’s well within the range permitted in Champagne. In 2013, our total vineyard yield was 36 tonnes. I’m almost embarrassed to admit it. However, our wine quality exceeded that of 2012. “What’s important about this system is that it’s resulting in the production of sparkling wines destined for the top of the premium segment. We’ve been able to achieve that with zero botrytis. I think that shows we’ve really cracked the fruitfulness issue that’s bugged this district. Equally important, my costs per tonne are lower than if I had done things with a conventional VSP. They’re about the same as those for a canepruned vineyard that’s machine harvested. “Of course, you need plenty of operating funds at the start of the season – particularly for early season shoot removal – but the payback comes at the end with better yields of very high quality fruit. I think that’s very good news for small growers. When you’re small, you don’t have the scale and opportunities to reduce costs. “I think it’s no coincidence the average Champagne vineyard is around 2ha. I think that’s a very realistic response to the kind of intensive, hands-on work that systems like this require. And when you look around Tasmania, you can see plenty of opportunities for the establishment of profitable 2ha vineyards. That’s a very good WVJ prospect for the industry.” V28N5