Adelaide Hills Crop Watch 180909

CropWatch 1-2 LEAVES EL 7 Recent weather prolongs budburst Checking the CropWatch sites this week it looks that vine growth rates have slowed due to cool nights and windy weather. Chardonnay have stayed around the 1-2 leaf stage (EL 78), whilst mid-bursting varieties such as Pinot Noir, Shiraz and Merlot have moved ahead to the same stage. Cabernet blocks are generally yet to show signs of full budburst. Cool nights again this week are likely to keep quick growth in check.

Frost Damage As the warmer days approach, frost warnings will become more frequent. Light, localised frosts have been recorded throughout the district earlier in the week. Frost damage will occur mostly in low lying, sheltered areas with little air flow. The table (below) indicates that levels of damage should be low.

Growth Stage Woolly Bud

Frost Damage Temp. -3.5°C

Greentip

-1.1°C

Shoots up to 150mm Shoots over 150mm

-0.5°C 0.0°C

This message from Adelaide Hills CropWatch was compiled for the week ending Friday, September 18th 2009 and will be updated prior to September 25th. More Pest and Disease information is available at www.adelaidehillswine.blogspot.com

Earwig Damage

– Earwigs are beginning to cause minor damage throughout the district. Some Chardonnay blocks have ‘lace’ damage to leaves. Earwigs often hide under the bark in the vine crown, or in the soil and trash around the base of the vine. Typical earwig damage can look as shown above.

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.

Weeds Be on the lookout for herbicide resistant Annual Ryegrass in your vineyard (right). These ‘super weeds’ first appear as a scattering of single plants or small patches of plants that survive after a glyphosate application. Levels of glyphosate resistance are very high in other regions – the Yorke Peninsula, McLaren Vale and the Clare Valley. If you have seen this problem on your farm, seek advice. It is important to stop this Ryegrass from seeding and increasing next year. If you continue to use glyphosate you only make the problem worse. Increasing the rate of application does not help, as the Ryegrass continues to thrive. In other ways some undervine weeds can be a positive to your vineyard. Generally, the health of you under-vine soil can be gauged by the numbers of and the species of weeds present. Lifeless, dead soils will often not produce significant germinations of weeds. These soils often present as being compact, with high levels of mosses and lichens growing on the soil surface. This can also be an indicator of high shading levels, poor air flow and the potential over-use of herbicides.

Good levels of winter germination can aid with soil structure and can provide a good habitat for beneficial insect predators and earthworms. Good weed control at this stage of the season will help assist the vine with an even bud-burst and increased vigour throughout the initial stages of canopy development. This may help vines push through any potential earwig and mite damage.

Wind Damage

– Wind damage has been reported in many blocks throughout the district. Monitoring this week has recorded minor damage to those exposed areas, mainly in early varieties such as chardonnay.

Shiraz, as shown left, is generally too short to have suffered significant damage. Good news! 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.