Curse of Colombian Waxweed

Colombian Waxweed in Flower
Colombian Waxweed in Flower

Bellingen Shire Council has an ongoing and strong commitment to supporting our Shire in the area of weed management and is currently working with landholders to control Columbian Waxweed and other highly invasive species such as Tropical Soda Apple and White Blackberry.

In the last 3-5 years a large proportion of Bellingen Shire has been infested with a highly invasive emerging weed, known as Colombian Waxweed (Cuphea carthagenensis). This small woody shrub no more than 50cm high has been dubbed by some as ‘fireweed’s evil cousin’ radically invading productive pastures, and rapidly producing thousands of viable seeds profoundly altering the integrity of the area it invades, resulting in limiting stocking rates and out competing desirable species.

Mayor Dominic King says “Our productive lands are extremely desirable and the envy of many in the state.  Under the Biosecurity Act 2015 all landholders have a General Biosecurity Duty (GBD) to prevent, eliminate or minimise the biosecurity risk, this goes for all weed species”.

Right now Columbian Waxweed is in full flower showing small purple-pink star shaped flowers. After having a favourable summer it is just about due to produce many hard small black seeds that will be spread by floods, machinery, ducks and at this time most importantly by bailing infested paddocks and moving the weed further around, the latter believed to be a major cause of the weeds spread.

Mayor Dominic King added “All people bailing their paddocks preparing for winter fodder should be aware of this weed and knowingly moving or selling infected bails is a serious offence under the Biosecurity Act 2015. Equally buyers should remain vigilant and leave bails together for several weeks before moving around paddocks and monitoring the site closely for emerging weeds like Columbian Waxweed, and other highly invasive and undesirable species like Tropical Soda Apple, a notifiable weed with a state wide control order on it”.

The NSW Department of Primary Industries and Local Land Services worked together in 2016 to develop a permit for herbicide control of Columbian Waxweed, APVMA Permit (PER82650) which includes a range of selective herbicides. Best practice farming will also help reduce the likelihood of infestations occurring by not overgrazing, overstocking, implementing a paddock rotation system and applying on-going pasture improvement practices.

Slashing and mulching are not recommended methods of control and can actually spread seed further as the sticky waxy coating of Colombian Waxweed results in seed sticking to the machinery. Colombian Waxweed also tolerates being cut short and usually develops a dense mat following slashing. In pasture situations with established infestations, control using herbicides is the most effective and practical method of control.

If you think you have seen any of the above mentioned plants or would like more information please contact Council’s Acting Manager Sustainability, Environment & Waste on 6655 7300.