Mid August: In the vineyard vines are beginning to break dormancy. At this point one of the vine pests reported is Grapevine Scale - pictured below.
Reports have been that scales have been seen in high numbers where they have been seen in previous years.
Cabernet Sauvignon, which has a tough bark, seems to help protect Vine Scale allowing their numbers to build up.
Vine Scale are commonly found in ‘hotspots’ generally in older vineyards.
Vine scales produce a number of eggs over several days. The eggs are laid under the cover of the adult "scales" which offer protection during development - right. The adult dies once it has laid its eggs. Eggs hatch into "crawlers", which are tiny legged creatures which settle down and become an immobile scale.
DJ's recommend using specialised pesticide oils as an initial option because of issues with insecticides affecting other insects including predators- bottom.
Ask us for specific rates and other information.
The scale insects' waxy covering makes them quite resistant to insecticides, which are only effective against the juvenile crawler stage. However, scales can be controlled through biological control by beneficial insects. Many wasp species lay eggs through the scales shell.
Table - Options for the control of scale (black IPM compatible, blue text IPM transition, not recomcmended in IPM vineyards). Information produced by http://cesar.org.au/