Signs on Popular Tourist Walk Educate on Cotton Bush

The Serpentine National Park has benefitted from on-ground control activities and interpretive signage through the successful delivery of a project by the Peel Harvey Biosecurity Group (PHBG).


The project delivered 4.5 days of cotton bush removal by the Ecojobs team and saw the installation of two interpretive signs along popular walking tracks within the Serpentine National Park.


The Federal Government’s Community Environment Program was developed to assist with small-scale, community-led environmental projects. The program funded over 22 million dollars worth of activities, with the finished date extended to 2021 to account for impacts from Covid-19.

Project applicants were invited to submit an application by their local Member of Parliament. The PHBG met with Andrew Hastie at the 2019 Food and Farm Fest to discuss project ideas and the Serpentine National Park was high on the agenda.


‘The SNP was the perfect choice for this grant opportunity because of the high social value of the site as well as the historical cotton bush infestations that were present,’ said weed education officer for the PHBG, Teele Hooper-Worrell.


‘The PHBG had received a high number of cotton bush reports from the community in and around the Serpentine National Park. Cotton bush is a declared weed that is highly invasive and it was impacting on the amenity of the popular tourist attraction as well as the possible threat of seed spread to surrounding agricultural properties.’


Federal Member for Canning, The Hon Andrew Hastie MP, recently visited the project site and congratulated the team on their hard work.

‘Cotton bush is a terrible weed that harms our region’s beautiful natural environment, as well as our agricultural productivity. The PHBG team are doing an excellent job combating cotton bush in Serpentine National Park and educating the community on effective control techniques. I commend the team for their efforts, and I’m pleased the Morrison Government has been able to support this important work.’


While on-ground works delivered immediate results, the inclusion of interpretive signage at the park aimed to increase the level of education around cotton bush control. Placed at prominent sites along popular walk trails the signs outline the impacts of cotton bush, an invasive declared weed. They also share the important message that for effective results the control methods for cotton bush changes as the plant matures.

Ms Hooper-Worrell explained that landholders could be forgiven for thinking that one size fits all for control of cotton bush, but actually, effective control techniques change as the plant gets older.


‘When cotton bush are small and soft they can be removed and left to degrade on the surface of the soil or slashed. As the plants mature and the stems become hard, slashing would only encourage them to reshoot. When the plants are older they need to be physically removed or treated with herbicide with any pods on the plant also needing to be removed and bagged to prevent further seed spread,’ She said.


Department of Biodiversity, Conservation and Attractions' Parks and Wildlife Service, provided access and support to the work being done within the park as well as installed the signs.


With Narrow leaf Cotton bush a declared pest weed in Western Australia, the control of this species in Serpentine National Park has been included in the Weed Action Plan for the Park and actively managed for the past several years,’ Senior Ranger, Paul Tholen said.


‘The persistence of this weed seems to be due to the difficulty in removing the mature plants from hard to get to places and the seed from these plants then reinvade areas previously treated.


‘This is why volunteers are so valuable in contributing to the control of this invasive species. Volunteers are able to selectively remove mature plants from the edge of waterways, along sloping sections of walk trails and deep into thick bushland to remove the mature plants and stop the spread of windblown seed. Without volunteers, weeds such as cotton bush will continue to flourish, which is why the Department is supportive of this volunteer based initiative, brought together so diligently by the Peel Harvey Biosecurity Group.


Work delivered as part of the Communities Environment Grant has helped the PHBG and DPaW to further strengthen their partnership. This has led to the development of ongoing works to extend cotton bush control with further funding opportunities.