Description
- Erect branched herb/shrub up to about 1 metre tall
- Leaves have black dots along margins, oil glands visible when held to the light
- Flowers bright yellow, five petals, black-dotted along margins
- Most parts of plant have black oil glands that produce a red fluid when crushed
St John's Wort Information Link
Flowering Times
• Spring to summer
Control Measure
• Hand removal of isolated plants
• Herbicides
Problems
• Known to cause photosensitivity in livestock, resulting in loss of condition, low productivity and – in extreme cases – death
• Prolific seeders with up to 30,000 per plant
• Seeds can remain viable for up to 12 years
