Environmental Weeds in Sydney North

• Noxious Weeds
• Other Significant Environmental Weeds
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Weed control

• Hand removal techniques
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St John's Wort

Botanical Name: Hypericum perforatum
Noxious Weed Category:
CLASS 4 in Sydney region


Source: Geoff Sainty : Alps Invaders

 
Special Note: Toxins in leaves can cause photosensitivity, hyposensitivity (heat and cold stress) and infertility in grazing animals.

 

Description:
 Originating in Europe, St John's Wort is an erect perennial herb or small shrub with a creeping rootstock to 1.2m tall. The plant readily invades unimproved overgrazed pastures.

The leaves show oil glands when held against the light.

Bright yellow clustered, flowering spring to early-summer. The dead brown flower stalks are clearly visible at other times during the year.

Egg-shaped capsule with many small, dark pitted seeds.

Dispersal:
Seed and stem pieces.

Impact on Bushland:

Control:

Manual:  
Chemical: Please contact your local control authority for advice on chemical control.

Similar Species:

Suggested Alternatives:

References: