About white bryony
White bryony is a soft, green, cucumber-like vine that climbs up to 6 m by means of its curled tendrils. It produces clusters of small cream white flowers in spring/summer, with male and female flowers on separate plants. On female plants these are followed by 8 mm berries, in bunches of 3 to 8 that ripen to light red from January to April. The shoots die back in autumn to a persistent perennial tuber.
Why we don't want white bryony in New Zealand
White bryony smothers and shades out whatever it grows on including native and desirable introduced plants. It is dispersed by birds and its tubers are hard to find. The fruit and tubers contain toxic alkaloids, which may be poisonous if consumed in quantity.
Where white bryony has been found
White bryony present near Aria and Mokauiti in the Waikato, and one large complex site near Taihape. Due to effective control since the 1990’s the remaining plants are now limited to difficult and hard to access areas, such as steep banks and cliffs above river gorges.
White Bryony eradication programme
White bryony is one of the species being eradicated through the National Interest Pest Responses programme. The eradication programme consists of controlling the infestations to prevent further spread, site treatment (which can be manual removal of plants or herbicide application) and monitoring until eradication can be declared. Due to the longevity of the tubers, sites must be monitored until they have been clear of plant material for 10 consecutive years to ensure eradication.
Biosecurity New Zealand works closely with regional councils, the Department of Conservation, and other organisations to eradicate white bryony from New Zealand.
National Interest Pest Responses programme
What to do if you find white bryony
White bryony is an Unwanted Organism under the Biosecurity Act (1993). Propagation, spread, display, and sale are all prohibited. It is also a Notifiable Organism, which means you must report all sightings to the Ministry for Primary Industries (MPI).
If you think you have found white bryony:
- freephone our pest and disease hotline on 0800 809 966
- don’t touch the plants or try to remove them
- take photos and leave the plants so they can be treated or removed safely without spreading them further.
What white bryony looks like
