The recent identification of 500 blackgrass seedlings on a mid-Canterbury farm highlights the importance of ongoing surveillance for this invasive grass weed.
MPI GIA spokesman Grant Boston, says the find was not unexpected and that it confirms the source of the black-grass contaminated ryegrass seed harvested last year. The plants in question were found in January, and carefully monitored in the field until they reached a growth stage that allowed clear identification.
Mr Boston says there is no need for alarm at the find, as the plants were all in the same 15m2 area, found early and securely destroyed before any seed had set. The area where they were found will now receive repeat applications of herbicides, from a range of modes of action, and be regularly mown to prevent plants heading.
Black-grass flowered considerably later this year than it has in previous years, highlighting the impact of climate variability on flowering.
Please monitor crops for the presence of black-grass and if you think you have found black-grass, please:
- Do not disturb any seed head.
- Take a photo of the plant.
- Contact MPI’s Pest and Disease Hotline on 0800 80 99 66 to report the find.