While spring flowers, early bumblebees and courting birds attract attention at this time of year, the humble but fascinating lichens just get on with doing their thing.

Lichens are different, a fusion of a fungus and a simple plant or alga, some are even more complicated with the simple plant being replaced by a bacterium that acts like a plant in having pigments that allow photosynthesis. The fungal part of the (what can you call them, they’re not plants, they’re not mushrooms, they’re more than just things), the fungal part of the lichen provides structural support and protection while the alga or bacterium produces nutrition for both parts by photosynthesis.

This joint collaboration allows lichens to thrive in all sorts on unlikely and even hostile places where the fungi, algae or bacteria could not survive alone. They can encrust tree branches, rocky cliffs, bare soil, even garden benches and gravestones.

There are populations adapted to living in most British environments depending on factors such as humidity, air quality and the nature of the substrate or surface on which they are living. Some lichens grow on limestone gravestones while different ones grow on granite. Bright orange Xanthoria parietina is a seaside specialist and the bushes on Peak Hill are covered by it. The Latin names can be very complicated and very few lichens have common names, but X. parietina is so distinctive in look and habitat it has acquired the very apt name Maritime Sunburst Lichen.

Even lichens are very different from other lichens. Some are a crust of coloured dots on a solid gatepost or rock. Others are a continuous crust as if thick coloured paint had been spilled and dried. Some are foliose as if they have small leaves that curl up at the edges, and then there are the crustose or bushy lichens. The Blackthorn hedges around the James Cornish Fields on Salcombe Hill have encrustations of all the different forms of lichen including some very bushy crustose lichens that hang like mini Santa’s beards.

Britain has over two thousand different species recorded and new ones are being recognised regularly, they are incredibly difficult to identify. Some species look so similar they can only be told apart because they turn a different colour when tested with chemicals such as potassium hydroxide. The yellow orange crusts of Candelariella stay yellow while the almost identical, even under a microscope, Caloplaca will turn crimson.

They are small and insignificant to many of us but they play important roles in the web of nature. As they are often the first living things to establish in an area, lichens create a foothold that allows other things such as mosses and tiny invertebrates to join them, and then other life forms can begin colonisation. Old lava flows will one day support forests because of the start to life given by lichens. They are famous for allowing reindeer to flourish in the Arctic. Their complex chemistry means some have great potential as sources of medicine. On a more prosaic level, their pigments come in a rainbow of colours and are great for dying fabrics. They really are fascinating things.