What does it look like?
Rhus tree (also known as Japanese wax tree) is a small deciduous tree or large shrub that is highly toxic and can cause allergic reactions. It grows to around 8–12 metres tall and has fine branches with leaves arranged in pairs, plus a single leaf at the tip. The leaves are 4–10 centimetres long and 2–3 centimetres wide, turning from bright green to orange or scarlet in autumn.
Very small yellow/green flowers appear along new growth in spring and early summer. The tree produces pale brown, papery fruit that hang in clusters through autumn and winter before dropping in spring.
Rhus trees are commonly found in coastal indigenous vegetation, urban gardens and wasteland. They tolerate a wide range of soil types and can become invasive in disturbed areas, forests, open woodlands, urban bushland, roadsides, gardens and waste areas in temperate and subtropical regions.
Why is it a problem?
Rhus trees produce clusters of brown fruit that contain large numbers of seeds, which are primarily bird or gravity-dispersed, though also easily relocated by human movement of soil. The seed remains viable for many years, and will germinate readily, with seedlings usually found near the parent tree. The tree may also reproduce vegetatively by suckering.
Rhus tree can cause a severe allergic reaction to humans if skin contact is made, especially with the sap. The sap has been known to hospitalise people if it gets on skin.
Control methods
Note that physical removal of trees is not recommended as this species has high associated risks of poisoning including that from old branches and leaves, making disposal of the plant material difficult. Stem injection of herbicide is recommended.
Herbicide control
- Drill & fill/stem injection using Glyphosate (360 g/l) undiluted 1–2 mL per cut.
- Stump paint - apply xtree basal as per label instructions or 250ml triclopyr + 750ml biodiesel (eg codacide) at up the stem at least twice the diameter of the tree.
- Picloram 44.7 g/kg + Aminopyralid 4.47 g/L (Vigilant II ®)
- Glyphosate 360 g/LRate: 1 part glyphosate to 1 part water
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.
