Vinehealth Australia has conducted a phylloxera surveillance program in South Australia since 2001. To date, no phylloxera has been found.
Benefits of the program
Aerial surveillance is both cost effective and efficient due to the large area of plantings, and high proportion of vines not grafted to resistant rootstock. It enables Vinehealth Australia to identify all vineyards for inclusion in the Vineyard Register, plan and coordinate outbreak management simulations.
STEP 1: Collection of Aerial Imagery
Aerial imagery is collected during summer, preferably at veraison when vine canopies are fully developed. This is the time phylloxera infested vines will be most distinguishable from non-infested vines.
STEP 2: Identification of Suspect Sites
Imagery is analysed using vegetation indexes such as PCD and NDVI. Phylloxera infestation symptoms include reduced canopy, shoot growth and yellowing of leaves. Infested vines will present in the imagery as an ‘oval shaped’ patch of low vigor.
Imagery of a vineyard in King Valley (Victoria, Australia) highlights sites of phylloxera infestation (arrowed).
STEP 3: Field inspections of suspect sites
Phylloxera infestation is only one cause of low vine vigour. Confirmation of infestation is required through ground truthing whereby roots are examined for the presence of phylloxera and galling.
Permission is always sought from grape growers before inspecting any vineyards and hygiene protocols are strictly enforced to prevent an inspector transferring pests, diseases or weeds between sites.