As growers may be aware the Riverland Viticulture Technical Group (RVTG) has been working on a Hard to Kill Weeds project focussing on Gazanias. The original Gazania trial site had some issues arise prior to spraying. For unknown reasons the weeds started showing signs of severe stress, making them unreceptive to the chemical applications. This site was abandoned and a new site at Century Orchards was set-up and pegged out ready for the trial to commence. Unfortunately the second site was hit hard with five consecutive frosts and temperatures as low as -5°C, only days before spraying was due to commence and the majority of Gazanias dropped their flowers (or flower petals) and showed signs of severe stress.
This outlines the climatic and agronomic issues that growers have controlling these weeds.
The RVTG feel it would be irresponsible to run a herbicide trial on stressed weeds with industry funds – the outcome would be meaningless. Other suitable sites for this trial are being sought for the trial to continue. The herbicide trial needs to start prior to the summer heat, otherwise it cannot start again until possibly July 2015.
If any grower knows of a site, measuring approximately 20m to 30m square, with good Gazania distribution and moderate to high weed density, please contact Matt Ward (0429 041 645) or Riverland Wine (8584 6399) as soon as possible.