I am often asked ‘what’s the point’ with invasive species management? Many people believe that we have nothing to fear from what they regard as ‘progress’ or ‘natural succession’. They point out that most studies show differing results when looking at invasive species; some suggest that we accept their presence without fighting back…
A recent article by biologists Kristen Powell, Tiffany Knight and Jon Chase of Washington University tries to find why opinion amongst “experts” differs so widely.
It was noted that most studies of the effects of invasive plants are carried out at a single scale. Some study biodiversity in square-metre quadrats whilst others scan entire regions.
Invasive species decrease biodiversity at the smaller sites but at larger scales the impact seemed to be less dramatic. This lead to a conclusion that the scale of the areas researched could cause conflicting results.
The research helps explain seemingly contradictory findings in scientific literature, but what does it mean for people tackling Japanese Knotweed in small areas as part of a neighbourhood improvement scheme?
Is it worth it?
Well the answer from the experts would be a resounding ‘yes’.
Invasive species are a huge threat; if we are going to deal with them, we need the cooperation of the public. Invasive plants have negative effects on plant communities at small scales - the scales that are crucial for ecosystems. To prevent turning our natural habitats into invasive-species monocultures we need people to remove them from their gardens, they must remove them from their neighbourhood and ensure they do not cause cross-contamination by casual dumping of cuttings and waste.
Invasive species are reducing the abundance of native species - but when you search for them in the UK, most species are still present; they haven’t gone extinct.
This means it’s not too late to restore habitat and increase the abundance of native species.
So in answer to the question - ‘what’s the point’ - the answer would be: any work done on a small local site will help protect our vital natural heritage and keep our bio-diversity intact. Think local; act global.