Triffid weed

Chromolaena odorata
Triffid weed: Chromolaena odorata Triffid weed: Chromolaena odorata

Common name:

Triffid weed

Scientific name:

Chromolaena odorata (Asteraceae)

Alternative common names:

Paraffin weed; Armstrong’s weed; Eupatorium; Chromolaena; Siam weed (English); paraffienbos (Afrikaans); usandanezwe (isiZulu)

Scrambling, sparsely hairy shrub up to 4m or higher, often forming dense thickets with wide-spreading branches. Light green leaves, often yellowish which smell strongly of turpentine or paraffin when crushed. White or pale blue cylindrical flowers appear from June to July. It produces straw-coloured, bristly fruits and this plant is poisonous.

Invades: Forest margins, savanna, plantations, wooded kloofs, water courses, roadsides

Additional Info

  • Where does this species come from?

    North, Central and South America (south-eastern United States to northern Argentina), as well as the West Indies

    What is its invasive status in South Africa?

    CARA 2002 – Category 1 NEMBA – Category 1b

    Where in South Africa is it a problem?

    Common throughout the lowlands of KwaZulu-Natal and into Swaziland, Mpumalanga and Limpopo Provinces

    How does it spread?

    Produces vast amount of wind-blown seeds

    Why is it a problem?

    It completely smothers and suppresses indigenous vegetation and known to replace up to 100% of indigenous vegetation in some regions. It is also highly flammable contributing to fires

    What does it look like?

    General description: A scrambling, sparsely hairy shrub growing up to 4m or higher and can form very dense impenetrable stands. Leaves: Light green, often yellowish, smell strongly of turpentine or paraffin when crushed. Flowers: White or pale blue in terminal, surrounded by speckled bracts. Fruit/Seeds: Straw-coloured, bristly achenes, mostly dispersed by wind.

    Does the plant have any uses?

    Planted as an ornamental plant but has now become a troublesome weed