Velvetleaf is still a concern and monitoring is ongoing.
Detector dog property inspections began mid-November in Auckland, Waikato and Horizons.
The cold and wet delayed maize planting, resulting in the emergence of velvetleaf on many properties. Small plants were found on properties in North and South Auckland and the Waikato, but none in Horizons.
Temperatures are predicted to increase over next few weeks and velvetleaf that has not been controlled by pre or post emergent sprays will be coming into flower early January. This means now is the time to be vigilant.
Keep an eye out when walking crops. New incursions will most likely (but not always) be the result of last season’s harvest, i.e. combines dropping seed(s) in the gateway or the first row. If you can find the first plant before it drops its 30,000 seeds, you’ll will prevent a lifetime of velvetleaf management. Take a photo of any plants you find and send them to sally.linton.nz@gmail.com for confirmation.
You can’t insure against biosecurity risk; so you need to manage it. Ensure your contractors undertake good biosecurity practices and that purchased crops are free of any unwanted weed, including velvetleaf. A little time, effort, and cost will pay off in the long term.
Photos: All the plants between the maize rows are velvetleaf.