From Viper’s-bugloss to Hairy Tare: Churchill College Plant Audit Uncovers 292 species

292 different plant species were identified on Churchill College’s campus during a year-long audit by Jonathan Shanklin, the Botanical Society of Britain & Ireland Recorder for Cambridgeshire, showing the impact of our Grounds & Gardens team in supporting biodiversity on site.

Churchill College’s near 50 acre site spans a variety of habitats including sports pitches, meadows, garden beds, copses, former private gardens in Storey’s Way, a winterbourne (weather-dependent stream) and isolated trees and lawns. Biodiversity is a prime consideration on our site, so as well as beautifully tended borders, we also make space for wilder areas, to allow many kinds of wildlife and plant life to thrive.

During 12 months from Autumn 2021 to Autumn 2022, Jonathan visited the site roughly quarterly to audit the plants in the grounds. He took a general look over the whole area, so there may still be some undiscovered gems, but the audit provides a good overview of the types of flora on site.

While almost 300 different plant species were identified, 15 were noted as species on the county Register of Plants of Conservation Concern. A further 34 were “axiophytes” which means they indicate a good or interesting habitat. The 292 species excludes all the planted trees and borders.

Jonathan noted that some of the axiophytes and RPCC species were introduced as part of the biodiversity improvement work undertaken by the Grounds & Gardens team. Some of these plants are becoming established, while others have either been present in the College grounds for a long time or have been able to arrive and persist thanks to the development of “nature friendly policies”. Notably not using total weedkillers and not spraying the lawns has encouraged more biodiversity.

When thinking about actively targeting areas for biodiversity improvement by introducing species, the Grounds & Gardens team have planted in order to add diversity as well as improve habitats. A large spring flowering bulbs project took place last year, and wildflower plugs and seed have been sown which are suitable for our site’s conditions. Other plants, like yellow-rattle were introduced to naturally slow the growth of the more vigorous grasses allowing the wildflowers to flourish.  Yellow-rattle is a hemiparasitic plant that grows on the roots of grasses.

Mistletoe is another hemiparasitic plant, which has both male and female forms. Mistletoe takes water and nutrients from the tree but it has green leaves which photosynthesise.  Mistletoe can weaken trees but rarely kills them so it’s allowed to flourish on site.

In the last year, the College has also invested in “green roofs”, using the covered walkways, bike sheds and garages to grow sedum. This has a twofold benefit, in that the plants help absorb some of the water and slows down the rest that goes into the drainage, and also creates more green space to support insect and other plant life.

As well as the proactive approach to planting, the Churchill College site has benefited from “natural” arrivals. These include the pyramidal and bee orchid, whose seeds only germinate if it finds the right fungal partner, subject to suitable habitat being provided. Hawkweed oxtongue and cotton-thistle are also new arrivals.

John Moore, Head of Grounds & Gardens, said “Churchill College is favoured with a wide variety of habitats across its acreage, and the Grounds & Gardens team work hard to make sure that biodiversity is supported and integrated across it. It’s been fascinating working with Jonathan, and it’s very rewarding to see efforts paying off with the wide variety of both established and new plants that the grounds support.”

Flora of Churchill College – 2021-2022

Botanical nomenclature follows Stace III.

Status: Ax = axiophyte. RPCC = Register of Plants of Conservation Concern.