Sniffing Out Velvetleaf as Summer Signals Emergence of Pests
Sniffing Out Velvetleaf as Summer Signals Emergence of Pest Plants
The arrival of warm, humid days means velvetleaf and other nasty weeds will be starting to appear on farms, prompting a plea for landowners and rural contractors to be on the lookout for pest plants.
Helping to sniff out velvetleaf in the Waikato region last month was Rusty and his handler John Taylor. The Southland-based pair visited 12 high risk farms, finding plants sprouting on 8 of them. They’ll be returning to carry out further surveillance work in the Waikato in late January and early February ahead of the harvest.
Waikato Regional Council’s biosecurity pest plants team leader Darion Embling said the wet winter and spring had delayed planting by farmers, but crops were now growing and it was the right time to be looking out for pest plants and acting to remove them.
“Pre-emergence spraying has been carried out by most farmers, but we’re getting reports from those which have previously had confirmed velvetleaf infestations that seedlings are pushing through.
“This is a critical time for control of pest plants, and in particular velvetleaf, with hand-pulling seedlings and post-emergence spraying essential to get on top of them,” Mr Embling said.
He added: “Landowners and rural contractors should be looking around gateways and the first 3-4 rows of crops for signs of velvetleaf. And if they spot this plant, they need to notify us for advice to avoid crop loss.”
Seedlings are vigorous, with plants left untouched growing rapidly in the first few weeks after germination. Its leaves are heart-shaped and velvety to the touch, and have a distinctive smell when crushed.
Velvetleaf grows up to 2.5 metres tall and has buttery-yellow flowers as it matures from spring through to autumn.
This aggressive cropping weed is one of the world’s worst. It damages crops by competing with them for nutrients, space and water, and its seeds can persist on farms for decades, even surviving digestion and silage processes.