Our Nature Ramble often takes us to far off places in search of endangered species, but we can look closer to home and still find marvels of nature on a stone wall or a park bench…
We peer into a tiny world where lichens become diverse landscapes
It took us an hour and a half to walk the 100 yards between the library and the village hall. Passers-by gave us curious looks: eight people closely studying the stones in a wall or the trunk of a sycamore. We were peering into a tiny world where lichens became diverse landscapes through the magnification of hand lenses. As the picture oscillated through the glass, I felt I was in another world. As if snorkelling among coral and rocks, a square inch of sandstone held ridges, chasms and depths.
Our group of botanists and learners was led by 91-year-old Geoffrey Chaytor, who has studied lichens for 10 years. Before the second world war, he photographed flowers with a plate camera; now he uses PowerPoint to illustrate his lectures. There were five species of lichen within a hand’s span on the wooden bench outside the library. With a pocket penknife he lifted the edge of foliose (leafy) lichens to show the black rhizines beneath; these roots anchor the thallus or body of the lichen to the wood.
The wind sent leaves scudding along the pavement, bringing the sound and scent of childhood autumns. Spiked shells of horse chestnut lay wedged between the coping stones of the stone wall, their conkers spilled on to the pavement. Lichens adhered to the uneven surface of the wall, colouring it yellow, grey and black. Some names reflected the way they grew. Rhizocarpon geographicum spread its indentations like a map. R concentricum, now called R petraeum, lay in concentric circles.
Buddleia seedheads, dry and dusty, drooped from front gardens as we counted 18 species of lichen. At the village hall a sign swung in the wind: “Today. Persian rugs for sale.” The patterns we were studying were on a different scale. A silver patch of Ochrolecia parella was revealed as a mass of puffy bumps, puckered like doughnuts. Leafy dog lichens sprawled in the grassy slope by the bowling club. As the autumn wind tugged leaves from the trees, lichens would still give their colour throughout the winter months.