Tree privet

Tree privet is an evergreen tree growing up to 15 metres tall with distinctive lumpy warts on the stems.

Description

• Leaves are dark green, glossy and arranged in opposite pairs on the stem.

• Flowers are fragrant, tubular, white with purple/mauve anthers (November-March).

• Fruit is purple/black and ripens in autumn.

• Seeds dispersed by birds, vegetation dumping, and soil movement

• Habitats include hedgerows, lowland and coastal forest, shrubland, disturbed sites, roadsides, wastelands, and wetlands.

What you need to know

Tree privet forms dense stands, displacing native vegetation and preventing native seedling recruitment. It dominates the canopy layer, altering vegetation structure and plant diversity. May cause an allergic reaction in some people, often as a cross-reactivity to main allergens.

Management approach

Tree privet is declared an unwanted organism by the Ministry for Primary Industries (MPI) because it is capable of causing harm to the natural environment, physical resources or human health in Aotearoa/New Zealand.

These species pose a high risk to our environment, economy, recreation, and cultural values.

Rules

Any species declared a pest cannot be sold or be in a place where plants are being sold. Pest plants cannot be propagated, bred, multiplied, communicated, released, caused to be released, or otherwise spread.

To help protect our environment:

Consider removing this invasive species from your property and consult your local council for appropriate disposal. Consider lower-risk alternatives for your garden, such as native plants.

Control

Physical control

Dig or pull-out small plants and seedlings

Plant parts requiring disposal: seeds.

Contact your local council for appropriate disposal locations

Chemical control

Cut plants close to the ground and immediately treat stump with herbicide gel containing glyphosate or metsulfuron-methyl.

Drill downward sloping holes around the circumference of the trunk about 8-10 cm apart, fill with 20g/L of metsulfuron-methyl or neat picloram.

Foliar spray with 0.5g metsulfuron-methyl plus 3ml penetrant per 1L of water.

Foliar spray with 6ml picloram/triclopyr mix plus 1ml non-ionic surfactant per 1L of water.

Caution: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.

Large trees must not be ringbarked or drilled that are closer than 1.5 times the height of the tree from paths, walkways, and property.

Trees over 4 metres in height should be removed by a qualified arborist.