Common name: Bomarea
Botanical name: Bomarea caldasii, Bomarea multiflora
Management programme: Progressive containment
Why is it a pest?
Even though its flowers are very pretty, if left uncontrolled bomarea can smother and eventually destroy your favourite plants in your garden. Bomarea invades remnant forest and shrubland interiors. The vines grow into the tree canopy and form large masses, which overtop and smother the supporting trees. Seedlings can establish in the shade of forest interior, creeping along the ground, strangling saplings and smothering low growing species. Extensive infestations in the tree canopy alter light levels, which can kill mature trees and prevent the establishment of native species.
The progressive containment programme aims to stop a pest from spreading and/or contain it to a certain area.
What does it look like?
Bomarea leaves are thin, pale green, long and pointed. It has trumpet-shaped flowers that are produced in drooping clusters of 15–20 flowers. They are red on the outside and bright yellow with red spots on the inside. The fruit is a capsule that ripens and splits to reveal bright orange/red fleshy seeds, dispersed by birds. Underground, the plant consists of a long rhizome (an underground fleshy steam) with roots and tubers that look like potatoes. The size of the rhizome and tubers is different depending on the age of the plant.
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When can I spot it best?
Flowering can occur at any time but primarily in early spring. Bomarea is known to be present, or has been present, across 650 properties in Dunedin City, Otago Peninsula, and West Harbour areas so if you’re in these areas keep an eye out and get rid of it.
What are the rules?
Everyone in Otago must eliminate bomarea infestations on the land that they occupy. The reason for this rule is to ensure infestation levels are reduced and threats to our environment are minimised.
How can I control it?
To prevent the spread of seed, remove all flowers and seeds as they appear.
Place seed pods in a black plastic bag, letting the sun cook the contents before disposing of them.
Where possible, cut the aerial vines and dig out all the rhizomes. Regrowth can occur from any rhizome fragments left in the soil.
The use of glyphosate based products have been found to be effective at a mixing rate of 1.5 to 2%. Vigilant or equivalent gel is also very effective when applied to freshly cut vines. It is not recommended that Vigilant is used too close to valuable or desirable species.
To protect the host plant from chemical damage, remove the bomarea, place it on the ground and then spray. Alternatively, cut the vines 150mm above ground level and spray or paint the freshly cut stems. (Beware of non-target damage as glyphosate is non selective)
Caution: When using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.
Disclaimer: Mention of product trade names does not endorse these products nor imply criticism of similar products not mentioned. The Otago Regional Council does not give any warranty that the information is accurate or complete or that it is suitable for all circumstances.
Eliminate - the permanent prevention of the plant’s ability to set viable seed
Land occupier – An occupier is the person who physically occupies the place, whether they own it or not. For example if you are renting a house owned by someone else that does not live on that property, you are the occupier and are responsible for pest management under the pest plan You can see more about the responsibilities of occupiers (including owners) in 3.3.1 section 3.3.1 of the pest plan