Adelaide Hills Crop Watch 021009

CropWatch 2-3 LEAVES EL 9 Slow vine growth continues Growth in all varieties has continued to be slow in across the CropWatch vineyards. The Balhannah Chardonnay is the most advanced at 3-4 Leaf (EL 9-11) with 5-14 cm shoots. Monitored Pinot Noir blocks at Forreston are the least advanced being between Rosette and 2 Leaf (EL 5-8) with shoots 0-4 cm long. Waterlogging and cold soil are slowing vine development this season compared to previous drier September. Frost and cold damage is noticeable in some blocks, although levels are generally minor.

Downy Mildew - low risk from the rain. The wet weather over the last few weeks is not likely to have caused a Downy Mildew Primary infection in your vines. Weather conditions at night were generally too cold (below 10oC) and the only marginal chance was on the 17th of September when temperatures were above 10oC. Fortunately vines were not advanced enough to be a significant risk of infection. We are entering the high-risk period when shoots are 10-30 cm long in the lead up to flowering. The risk of crop loss lasts until the berries are set and have reached 3-6mm in size.

This message from Adelaide Hills CropWatch was compiled for the week ending Friday, October October 2th 2009 and will be updated prior to October ctober 9th. More Pest and Disease information is available at www.adelaidehillswine.blogspot.com

Powdery Mildew

– The creeping disease. The best time to control this disease is in the early season by limit the spread of any Powdery Mildew flagshoots and stopping any bunch infection during flowering. A rough rule of thumb is start control when shoots are 20-30cm long, or 2-3 weeks past budburst as pictured (above).

Many growers have been having good success by treating each vineyard A low risk approach is to include patch based on its disease risk. They have been using high pressure a registered Downy Mildew programmes for blocks with a history of Powdery and lower pressure protectant with your scheduled programmes on those that have been free of disease. fungicide sprays. 1 CropWatch SA Adelaide Hills is a service provided by service provided by the Adelaide Hills Wine Region Inc. DJ’s Grower Services provide vineyard monitoring data, interpret weather data & compile the messages. Information is general in nature. Always seek professional advice specific to your vineyard. All photos (c) James Hook, Richard McGeachy & Peter Magarey unless noted. CropWatch acknowledges the support of James Hook & Matthew Wilson in preparing this message.

Hail Damage Hail has damaged blocks at all of the CropWatch Adelaide Hills sites. Vineyards in Meadows have been hit the worst with high levels of shoot bruising and leaf tear recorded. Some vineyards may benefit from ‘healing’ foliar fertilisers or preparations. Additionally the application of a Botrytis preventative may be required on badly damaged blocks as part of an early spray round. Note that some wineries have had residue issues with overuse of the product Captan, a Group Y (M4) fungicide, commonly used for these protective sprays. Consult your winery or advisor if you are in doubt about your options. Right: Leaves torn by hail. Hail causes variable damage that may lead to botrytis infection of shoots, leaves and bunches. Monitor for; -

Damaged inflorescences.

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Irregular pitted marks, mainly on the windward side of shoots and canes.

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Holes in leaves.

Earwig Damage

– Earwig damage has increased this week. All of the CropWatch vineyards checked this week showed signs of Earwig damage. In some cases this has been holding back vine growth. Earwigs are nocturnal. They shelter in dark spaces during the day such as under bark or on the ground under organic matter or in the soil. A sharp kick to the vine trunk should cause many earwigs that are sheltering in the vine to fall to the ground. Alternatively, scrape the soil and organic matter at the base of vines looking for earwigs sheltering there during the day. Also look for kangaroo damage where whole shoots have been bitten off or snapped as shown left.

CropWatch SA Adelaide Hills is a service provided by service provided by the Adelaide Hills Wine Region Inc. DJ’s Grower Services provide vineyard monitoring data, interpret weather data & compile the messages. Information is general in nature. Always seek professional advice specific to your vineyard. All photos (c) James Hook, Richard McGeachy & Peter Magarey unless noted. CropWatch acknowledges the support of James Hook & Matthew Wilson in preparing this message.