Environment Waikato is urging farmers and others with ragwort on their land to control it now before spring growth takes off.
Ragwort is a weed that reduces the productivity of land and is particularly toxic to cattle and horses. It is a biennial herb growing up to a metre tall which may also taint milk and honey. Each plant can produce more than 50,000 seeds that remain viable for at least eight years, and it can reproduce from crowns, roots and seeds.
It is widespread throughout the Waikato and can be spread by livestock and in contaminated hay. It is also common on waste land, river beds, swamps and open forests, quickly dominating pasture to the exclusion of other plants.
Under Environment Waikato’s Regional Pest Management Strategy, ragwort has two control standards for different parts of the Region, depending on how prevalent it is. The aim is to prevent its spread into un-infested pasture, and reduce and contain infestations.
Environment Waikato congratulates farmers for the gains made over the past few years in reducing the amount of ragwort in the Region. It is a plant pest of particular significance to farming communities and higher farm returns and land values help with higher compliance.
In the Hauraki, Thames Coromandel, Waipa, parts of Franklin, Waikato, Matamata, Piako, South Waikato and Otorohanga and Hamilton city areas it is a “total control” plant pest. This means that all plants must be removed and prevented from flowering.
Landowners should control the plant now by spraying before plants get bigger, with a follow-up later in the spring. Removed flower heads should be burnt to prevent seeds from ripening.
A biological control programme is also operating using the ragwort flea beetle at a number of Waikato sites. Beetles are collected and released to other areas.