Saffron Thistle

(Carthamas lanatus)

Total Control Pest

The tall stem, prickly leaves, and yellow flowers of Saffron Thistle.

Saffron Thistle is a prickly annual to biennial herb with woody stems. The plant is well-branched, carrying prominent spines and small yellow flower heads. The leaves of the plant have a greyish appearance. The seed life of Saffron Thistle is greater than 20 years; eradication is a long-term goal.

Reasons for the Strategy

If uncontrolled, Saffron Thistle can form impenetrable, dense stands and can potentially devalue fibre, injure stock and can interfere with cereal harvesting. It is not browsed, and is a threat to pastoral arable production.

Saffron Thistle is assessed at “3” on the infestation curve. There are known sites at Eighty-Eight Valley, Pig Valley, Pangatotara, Cable Bay, and the Maitai Valley. The low incidence of Saffron Thistle 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 Saffron Thistle 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 production and the increased cost of control in the future.

Strategy Rule for Saffron Thistle

The occupier shall destroy all adult and juvenile forms of Saffron Thistle on land that they occupy. A breach of Strategy Rule 4.11.5 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 Saffron Thistle, under Sections 52 and 53 of the Act.