Rhus tree

General description

Deciduous tree < 8 m tall. Leaves are pinnate, < 40 cm long and turn red in autumn. Flowers are yellow/green and borne in inflorescences < 20 cm long. Fruit is < 1 cm in diameter.

What you need to know

To help protect our environment:

• you must not breed, distribute, release or sell rhus tree within the Auckland region
• you must not plant rhus tree within the Auckland region, unless you are transferring an existing plant on your land to another location within the boundaries of the same property
• you must destroy any rhus tree on land that you occupy if it has been planted in breach of the above rules and you are directed to do so by an authorised person.

Auckland Council will control rhus tree at all sites within the Aotea / Great Barrier Island group where it is known to occur.

If you see rhus tree anywhere on Aotea/Great Barrier Island group, please report it to Auckland Council at pestfree@aucklandcouncil.govt.nz.

Habitats

Urban and coastal habitats, wastelands, forest margins, beneath semi-open canopy.

Dispersal

Seeds dispersed by birds. Vegetative spread from suckering.

Impact on environment

Allergenic and poses high risk to human health. Sap can cause severe contact dermatitis.

Control

Site management

Follow up treated areas 3 times per year. Encourage natural regeneration of native plants or replant treated areas where possible after 2-3 treatments to establish dense ground cover and minimise reinvasion.

Recommended approaches

Physical control

Method: Dig out with care to avoid any skin contact.

Plant parts requiring disposal: All parts.

Disposal options: Remove to greenwaste or landfill.

Biocontrol

Biocontrol is currently not available for this species.

Community agrichemical control recommendations

No qualifications: Cut stump and paste freshly cut base of stems with metsulfuron gel. Ringbark stem and paste with metsulfuron gel.

Basic Growsafe certified: Cut stump and spray freshly cut base with 5g metsulfuron-methyl per 1 L of water.

Certified Handler / experienced agrichemical user: Drill and inject trees with 10g metsulfuron-methyl per 1L of water if safe to do so. Drill 18mm holes (tangentially angled downwards) in a spiral up the trunk. For 50mm stems drill one hole. For 100mm stems drill two holes.

For larger stems drill holes 150mm apart. Foliar spray seedlings with 5g metsulfuron-methyl per 10L of water and 20ml penetrant

Safety notes

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.