The humble dandelion, often overlooked as a weed, has been identified by a Worcester ecologist as a major contributor to boosting the number of bees in urban areas.
Dr Duncan Westbury, from the University of Worcester, is calling on the public to think twice before mowing over dandelions or spraying weed-killer, in an effort to stop the decline of bee populations.
Simple measures such as not cutting small areas in your garden, or the council not cutting the full width of road verges can provide opportunities for so called weed species to flourish and benefit bees,” he said.
Dr Westbury, Senior Lecturer in Ecology and Environmental Management, was part of a major study of wildflowers in four UK cities, as part of the Urban Pollinators Project. The study focused on providing resources for pollinators, principally bees, and included experts from the Universities of Bristol, Edinburgh, Leeds, and Reading and aimed to help conservationists understand how to boost bee numbers in urban areas.
Researchers measured how much pollen and nectar different plant species produced and at what times of the year, and took measurements from over two million flowers to compare differences between annual and perennial plant species.
Dr Westbury said the study revealed the importance of dandelions in helping bees, as this species was in the top five nectar producers.
“It is evident that dandelions have a role to play early on in the year,” he said. “Dandelions are particularly valuable in March and April because there are not many other flowers around at that time.”
Dr Westbury advised on how to establish and manage annual and perennial wildflower meadows that were created in urban parks and schools in the four university cities.
Annuals flower the first year after sowing then die off while perennials continue to flower every year.
Results recently published in the journal PLOS ONE revealed that the perennial meadows produced on average 20 times more nectar and six times more pollen than areas sown with annual species.
The perennial meadows also provided resources for bees earlier in the season and throughout the year.
Dr Westbury said the Urban Pollinators project clearly demonstrated the value of establishing wildflower meadows in urban areas and that results from the study could also help guide the development of seed mixes to ensure they include species that produce the most nectar and/or pollen and throughout the year.
He added: “We know that urban gardens are good for bees, but if residents continue to tarmac or pave their front gardens, or put down artificial turf, our urban parks and schools are going to be increasingly important for providing for bees.”
To read the full paper go to PLOS ONE.