The Overberg is preparing for the next fire season as it heads into the summer months following a relatively dry winter.
The fire season in the Overstrand starts in November and in December the rest of the Overberg.
Chris Martens, of the Fynbos Trust and board member of the Greater Overberg Fire Protection Association (goFPA), says there is a close connection between fire and invasive plants. “Invasive aliens are a huge wildfire threat in the Overberg. Fires burn hotter and more often in our fynbos landscapes and the urban interface because of these plants. They change fire behaviour and they alter fire regimes.”
Wildfires can also undo all the work and money landowners have spent on alien clearing. That’s because fires stimulate the seed of invasive species, especially the likes of Port Jackson (Acacia saligna) and Long-leaf wattle (Acacia longifolia).
“These seeds can remain in the soil for a hundred years and more, and will always outcompete indigenous fynbos after a fire,” Martens explained.
Using fire to manage invasive species
But fire can also be used as a potential tool to manage aliens. “Landowners can use fire to help manage their invasive plants,” Martens warned, “but this needs to be done with careful and clever planning, and should never be done in an ad hoc way.”
The Greater Overberg Fire Protection Association is now teaming up with the Fynbos Trust and other partners to encourage landowners to start addressing the threat of invasive plants through fire.
Mitch Afrika, Extension Officer of the goFPA, says the first step is to ensure farmers and property owners have the right information to develop an integrated fire and invasive alien management plan.
He says landowners should identify management units where these integrated activities can take place. These should be chosen based on things like the size of the area, the fire history, the ability to control fires, and whether it’s close to infrastructure. They could even look at conservation priority areas, such as rivers and wetlands, to increase water flow once the plants are removed.
Once the management units have been selected, landowners should carefully plan their next steps. Reducing the threat
“Know what aliens you have and how much you have,” said Afrika. “Fire breaks need to be in place. Only then can planned burns be undertaken, with follow-up invasive alien clearing ready to take place when the invasive seeds germinate. The tip for landowners is to plan management activities in a way that allows fire to remove invasive plants cost-effectively.”
Martens explained that managing invasive plants and wildfire not only reduces the threat to infrastructure, it also reduces the severe impact fires have on fynbos landscapes. “While fynbos is a fire-driven ecosystem, too frequent fires have devastating results. They can lead to plant extinctions. Unseasonal and short-rotation burns can destroy much of the wildlife.”
The Overberg District Municipality’s Chief Fire Officer Reinard Geldenhuys warned that as invasive plants continue to overwhelm the natural landscapes, the dangers of wildfires increase.
“Every year we see how these alien species make it more difficult for fire fighters to extinguish fires. If we can’t start to bring these invasions under control, we face even tougher fire seasons in the near future.”
Visit the goFPA website www.overbergfpa.co.za and Facebook page for more information on how to compile integrated fire and invasive alien species plans. The WWF South Africa-funded handbook, “A practical guide to managing invasive alien plants” is available free on the WWF South Africa website (www.wwf.org.za).
