Cotoneaster franchetii. Photo credit: Royal Horticultural Society
It almost sounds too good to be true; but environmentalists will be thrilled. Scientists in the UK say they have discovered a common plant that helps to soak up the air pollution created by traffic on busy roads.
The plant, named Cotoneaster franchetii, is said to be at least 20% more effective at soaking up pollution, versus other shrubs in the study.
According to the sustainable horticulture charity, Plants For A Future, cotoneaster it is an evergreen shrub growing to 3m x 3m. It is common in Britain.
A study, published this week in a scientific journal by researchers from the Royal Horticultural Society (RHS), examined the effectiveness of hedges for soaking up air pollution and compared different types of shrubs such as cotoneaster, hawthorn and western red cedar.
Among other things, the RHS is working to use gardens and green spaces to help reduce environmental problems such as air pollution, flooding and heatwaves.
Perhaps surprisingly, the hairy-leaved Cotoneaster franchetii was very effective at reducing pollution on busy roads, but it had little impact on pollution levels on quieter thoroughfares.
“On major city roads with heavy traffic, we’ve found that the species with more complex, denser canopies and rough and hairy leaves such as cotoneaster were the most effective,” explained Dr Tijana Blanusa, the lead researcher for the project.
“We know that in just seven days a one-metre length of well-managed dense hedge will mop up the same amount of pollution that a car emits over a 500-mile (805km) drive.”
The research indicated that cotoneaster is ideal to plant along busy roads in pollution hot spots, while in other areas – where encouraging nature is more important – a mix of species would be more appropriate.
Plants For A Futuresays Cotoneaster franchetii is in leaf all year, in flower in May, and the seeds ripen in October. The species is hermaphrodite (has both male and female organs) and is pollinated by flies and midges. It is noted for attracting wildlife.
Prof Alistair Griffiths, Director of Science and Collections at the RHS, said the organisation is continually identifying new ‘super plants’ with unique qualities which, when combined with other vegetation, provide enhanced benefits while providing much-needed habitats for wildlife.
“We’ve found, for example, that ivy wall cover excels at cooling buildings, and hawthorn and privet help ease intense summer rainfalls and reduce localised flooding. If planted in gardens and green spaces where these environmental issues are most prevalent, we could make a big difference in the fight against climate change.”