Senegal Tea

(Gymnocoronis spilanthoides)

Total Control Pest

Senegal Tea is a semi-aquatic, perennial herb. When flowering, the plant may grow up to 1.5 metres in height. The plant has dark green leaves and white flowers. The plant flowers in summer and autumn. Senegal Tea has been sold as a pond plant. Distribution occurs by human or machinery movement, or through vegetative fragments being spread by water.

Reasons for the Strategy

The dark green stem and white flower of Senegal Tea.

Senegal Tea is an extremely aggressive, freshwater weed that inhabits wetlands, and still and flowing water. It forms dense floating mats that can quickly cover waterways and exclude submerged native flora species. It can impact on the habitat of fish, and heavy infestations reduce oxygen available to fish. It also impedes the flow of water and interferes with recreation activities.

Senegal Tea is assessed at “3” on the infestation curve. There are three known sites of Senegal Tea in ponds in Upper Moutere and Motueka, none of which are active. The low incidence of Senegal Tea in the Tasman-Nelson region, extensive areas of suitable habitat, and the potential for it to cause significant adverse effects, mean the benefits of total control far outweigh the costs.

Objective

To contribute to the eradication of Senegal Tea by ensuring that all known sites in the Tasman-Nelson region are inspected annually and all live plants are destroyed during the term of the Strategy.

Alternative Measures

The alternative option of “do nothing” or relying on voluntary control will not achieve the objective of eradication, and will result in significant additional costs to the community with respect to lost natural values and the increased cost of control in the future.

Strategy Rule for Senegal Tea

The occupier shall destroy all adult and juvenile forms of Senegal Tea on land that they occupy. A breach of Strategy Rule 4.12.5 is an offence under Section 154(r) of the Biosecurity Act 1993.

Biosecurity Act Requirement

No person shall knowingly sell, propagate, breed, release, or commercially display Senegal Tea, under Sections 52 and 53.