St John’S Wort

Also known as:
St Johns Wort
Europe, West Asia, North Africa

General description

Erect perennial herb <1.2m high. Reddish stems with 2 longitudinal ridges. Green leaves, studded with oil-bearing glands. Clusters of yellow flowers (Dec-May). Sticky, dark fruit.

Tussock grasslands, pasture, roadsides, waste places. Prefers cooler areas

Seeds spread by birds, animals, on machinery & in hay.

Poisonous to livestock especially sheep causing photosensitivity (sunlight intolerance).

Site management

Can be left in regenerating bush & shrubland, as will disappear as light levels fall. Chrysolina beetle may need to be reintroduced in some areas. Combination of beetle & herbicide treatments usually sufficient to minimise effects in most habitats. NB sprayed plants will remain toxic to stock.

Recommended approaches

1. Ensure Chrysolina beetle is prevalent.
2. Grub out individual plants.
3. Weed wipe spring to summer (300ml glyphosate + 2ml penetrant/L or 5g metsulfuron + 2ml penetrant/L).
4. Spray spring - summer (100ml glyphosate + 20ml penetrant/10L or 1g metsulfuron + 20ml penetrant/10L or 60ml Tordon Gold + 10ml penetrant/10L).

Caution: when using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.