Chromolaena Odorata
Family: Asteraceae
Common Name: Hagonoy, Jack in the Bush, Siam Weed, Christmas Bush
Origin: South America and Central America
Reference: Global Invasive Species Database
An Assessment of the Genetic Diversity and Origin of the Invasive Weed Chromolaena Odorata (L.) King and Robinson in South Africa
A thesis submitted in fulfilment of the requirements for the degree of MASTER OF SCIENCE of RHODES UNIVERSITY by INGE VON SENGER July 2002
- “C. odorata is regarded as the worst alien invasive plant species in the subtropical regions of South Africa”
- “It is an aggressive, fastgrowing weed (Liggitt, 1983), which is said to have one of the greatest impacts of all alien invasive
plants in the Old World tropics and subtropics (Zachariades et al., 1999)” - “Plant diversity has been reduced in reserves, affecting all other dependant life forms (Coetsee, 1995)”
- This species has been nominated as among 100 of the “World’s Worst” invaders
- It causes skin complaints and asthma
- It is toxic to animals
- It’s beneficial uses are as green manure crop, to repel mosquitoes and snakes, fish poison, and repels rodents from maize
- In the Global Invasive Species website, it says “is sometimes encouraged for use in shifting slash-and-burn agriculture to compete with Imperata cylindrica (alang alang or cogon grass), which is harder to control”
- Whee! Cogon grass is even harder to control!
- will add a picture of the flower when it blooms





Yikes! I think I have this on our farm too!! I’ll take pics of the one I hate the most – PAINFUL!
The ones I see now are in flower. I will post pics of the white flowers.
great help for our science investigatory project
big help for us studying fORESTRY