Back in June, perhaps some of the Graphene Week 2015 attendees spotted this little patch of wildness on the roof of the National Graphene Institute at the University of Manchester. This green roof was installed as the building was nearing completion in 2014 and is part of the commitment to improving the University’s campus as a habitat for wildlife. The University’s green roof policy can be found here, along with the other University policies about environmental sustainability.
Ahead of Graphene Week, the Biodiversity Working Group put together some information about pollinators, their requirements and the urban environment in order to have a sign in place for the delegates to read. This roof is particularly designed to attract bees, both wild bees and the honey bees from hives on roofs of the Manchester Museum and Whitworth Art Gallery.
The roof was created with a ‘sedum and wildflower’ mat made up with 21 different species. The low-growing sedums are now most visible around the sloping edges of the meadow, and taller species seem to dominate towards the middle. However, perhaps that’s not true; the sedums may be just hidden by the taller growing plants.
This summer, the Faculty of Life Sciences has arranged for a student to survey the roof to see how the plants are distributed. The Biodiversity Working Group will be continuing to monitor the roof’s progress to see how the composition of plants changes from this baseline. Some plants are likely to thrive, some will struggle and other’s will arrive as seeds blow over the roof or fall off people’s clothing.
For the past couple of weeks, I’ve been watching a patch of ground on my way to work. The soil is thin (I suspect it mainly consists of brick rubble) and consequently the grasses don’t grow very well. Instead it’s been growing a selection of plants with more insect-friendly flowers. Nothing rare or unusual, but a selection of wildflowers which thrive in an urban area and can attract plenty of pollinators.
Last week it was a foot tall, with red and white clover and buttercups already in flower. The buds of the oxeye daisies were getting ready to burst and the birdsfoot trefoil and common knapweed and were growing vigorously. This week, it’s been mown. I was expecting it to be a riot of colour by the end of the week, but instead it’s a green desert.
It already had a margin mown around the edge to allow visibility for traffic and a path through the middle to let people cut the corner. It’s near a busy road and no-one uses it as a lawn to sit or play games on. I think it would have been much better left to become a flower meadow over the summer (and the museum bees would certainly have liked it) and mown later in the season. I agree with Plantlife and Springwatch: ‘Say no to the mow’!