Robert Gilles
Monash,
Riverland, SA
An intimate understanding of the subtle factors at work in the `microclimate' of Riverland vineyards, has been worth at least $25 000 to grape grower, Robert Gilles. "We have probably saved a lot more - we used to sit on tractors spraying two days a fortnight through the growing season for nothing," he says. |  |
A build up in humidity gets powdery mildew going while rainfall splash above certain temperatures encourages development of downy mildew.
" Before our microclimate stations, we used to use rules of thumbs to predict outbreaks of disease from regional reports. There was a lot of guessing going on and people were out there spraying because it was the done thing to do. Yet disease risk could vary widely from one district to the next," he says.
"Now using the climate stations, we have cut back our spraying by 50% and we can stay away from the more expensive sprays that tend to have longer witholding periods before harvest."
Inspired by the vision of local researcher, Peter Magarey, (SA Research and Development Institute) to find a way to reduce preventative disease costs, Robert seized the opportunity to set up a microclimate station on one of his three blocks five years ago.
Now a 60 km stretch of irrigated vineyards between Renmark and Waikerie is dotted with the stations, becoming the envy of grape growing regions throughout Australia.
"The great thing about these stations is that we get specific disease scenarios for our district - and clear options about what to do.
"For the most part, the advanced warning means we only need to spray phosphoric acid, which is low on residue. In fact, the phosphorus ends up being a harmless fertiliser for the vines."
The microclimate stations monitor temperature, rainfall and rate of fall, humidity, the wetness of leaves and how long the leaves stay wet. Every three minutes observations are recorded and later automatically downloaded to the nearest research centre. There, computer models predict disease scenarios for each district. Robert receives updates of results and recommendations by fax.
Robert is an active member of the Riverland Agricultural Bureau, where he is involved in the Crop Watch program that looks at how to get better yields and quality with less input. As the owner of three blocks, growing red and white wine varieties, he produces about 450 tonnes of grapes - worth about half a million, currently contracted to BRL Hardy.
He says the success of the microclimate stations comes from the collective input of farmers through the agricultural bureaus and the Vine Improvement Society, backing up researchers' efforts. More recently the wine companies have lent their support, as they recognise the value in minimising spray residues.
"I got started with our microclimate five years ago when our bureau put in $5000 to install a station. One thing led to another and more were installed around the place.
"Initially when the stations came out, we wondered if they would work.
"But we have been able to prevent really bad losses from better timing the sprays. Even though conditions for a disease outbreak were really bad three years ago, we didn't lose much."
Robert confesses laziness was a prime motivator and his lifestyle has improved drastically.
"Not everyone loves to sit on a tractor two days a fortnight. Our life used to revolve around preventative treatments which meant going out and plastering the vines green with copper compounds. These used to shut the vine down for a while so we would lose growth and yield."
Robert says that none of the growers would be in a position to individually carry out the work of the microclimate stations.
"It's a fantastic investment that goes a long way, costing us just 20c/tonne of grapes to access the results.
"Now the stations are the cornerstone of an integrated disease control strategy that works better for us, the wine makers and consumers.
"These days it would be sheer stupidity to lose a few tonne of fruit to disease, by being unaware."