Submitted by Jessica Haskell on Tue, 2021-06-29 10:33
In October last year the University launched its 10-year vision for biodiversity and accompanying Biodiversity Action Plan. Since then, our grounds teams have been hard at work making sure our targets are turning into action across the estate. Wildflower and improved pond areas have been a huge hit with the local wildlife but unfortunately, due to Covid-19 restrictions, many Cambridge staff and students haven’t yet had a chance to see the changes.
Wildflowers spring up across West Cambridge
To give you an insight into our on-the-ground improvements, I took my camera out with me on my daily rounds in West Cambridge. Below you can see a fantastic transformation outside the Vet School (Veterinary School). Back in 2020 we cleared 30-40 tonnes of stump grindings and rubble from this area and replaced it with two types of new soil. The 150m strip shown below is a 50/50 mix of soil with a lot of sand and not a lot of nutrients in (this is where we planted the wildflowers as they like nutrient-poor soil). The surrounding grass area is a lawn repair mix which has nutrients in and we also planted three different types of mountain ash (rowan) as well. The wildflower area thrived quickly and we cut it back in July 2020 to encourage growth. Hopefully it’s clear that the second picture is our ‘after’ photo, taken in May 2021 when the area was full of colour, diversity and visiting wildlife!
Reaching for the sky
Always up for a challenge, my team used lockdown to take the University’s biodiversity efforts to the next level. On top of the Maths Building (Faculty of Mathematics) is a 350m-rooftop wildflower area. Unfortunately, it has struggled to thrive as a standard green roof, as its south-facing aspect resulted in dead and dried grass rather than a buzzing biodiversity area. Maintenance is also difficult when you’re this high off the ground. As you can only access the space by lift, there’s a limit on the gardening machinery you can bring up to the roof. By planting a wildflower area however, we have not only supported wildlife, we’ve also reduced the need for cutting to just once a year!
Determined to revive the area, we sprayed the weeds off over a 6-month period, raked off all resulting debris, and then covered the area with a Hessian/jute webbing (shown in the first picture). The webbing binds the whole habitat together before rotting down as the lawn becomes more established. A 2m-wide band of grass was sown around the edges on the more level areas, whilst the rest was planted with a mix of ground and short wildflower seed2. After all this, the area was covered with over 4 tonnes of sterilised soil. Our hard work in preparing the area has already been rewarded, the seeds have successfully grown up through the webbing and soil, providing a welcome and unique biodiversity haven high above the offices.
Protecting what we already have
Establishing new wildlife areas is immensely important, but so is improving and protecting the biodiversity already found across the estate. From the University’s Biodiversity Baseline Summary Report, we know we have areas of orchids including bee and southern marsh orchids. We have added stakes to the ground to prevent these being inadvertently cut or mown. In the Vice Chancellor’s garden, to name just one other area, we have created new wildflower areas but also simply left areas un-mown to create a mosaic of different habitats. On a larger scale, over at West Cambridge Lake we have coppiced the willow around the lake to create a varied age structure. By relaxing mowing around the lake we have also helped establish wet grassland areas with thriving rushes, cowslips, reedbeds and alder carr.
If you’d like to see some of these spaces for yourself, you can join me on an informal guided walk on 20 July, 12:00-13:30 as part of the University’s 'Spot On!' biodiversity campaign launching this month.
Written by Mark Jermy, Senior Grounds Supervisor
Photo credits: Mark Jermy (before images), Rachel Steward (after images)
1 Mixes used from Barenbrug:
- Ground cover
- Short
- Tall
- Red white blue
- Universal
- Bees and butterflies
2 Mixes used from Barenbrug: