At the end of the old millennium the first thing I wanted to plant in our new garden was a mixed native hedge. I wanted, a little naively, to return some of the land we had bought to what I imagined had been an older, perhaps better landscape. The previous owners had run their children’s ponies on the rough grass of a former arable field. Before that, nineteenth-century maps show a tree dotted patch of ground.
I also felt I wanted to be part of that growing movement to redress the post-war purging of hedges which had seen fifty percent of our hedges lost across Britain and much of what remained in a poor state; more lines of trees, long outgrown, rather than fully functioning hedges.
Hedges had come and gone over time, often contentiously. The post-war decline was fast and it didn’t happen in isolation. Post-war hedge removal was part of rapid changes to the landscape, caused by direct grubbing up and indirect means such as pollution, disease and climate change. It could proceed quickly in part because machines replaced human labour.
The same applies to the equipment for maintenance. At the 1948 Royal Show the McConnel Company launched their tractor mounted hedgecutter, invented by a Scottish farmer. Technology offered a bright shiny new future.
There were seemingly good reasons for changing the landscape in this way - to improve our food security and provide food at the lowest possible price by making agriculture efficient, able to maximise the potential of bigger and better agri-machinery. As hedges went biodiversity declined and what remained became increasingly homogenised.
I quickly learned that what I wanted for the garden, as well as these links with the past, was very practical: a windbreak to soften the frequent southwesterlies and the occasional northerlies that took their toll on my other nascent garden plants and my fingers in the winter. Hedges are the best semi-permeable wind filters. Ideally they reduce the strength of the wind but still allow 50-60% of the force to move through but in a controlled way.
I hoped too for more insects and in turn more birds, that a toad might like the leaf litter that would accumulate, that the bats that were evident in our first few warm autumn evenings could benefit if I joined up the hedge that led to oldish trees in my neighbour’s garden with those on the top boundary of mine, filling the gap in between, extending the linearity.
I knew less about hedge plants then, and the best ways to plant them so I found myself mesmerised by the hedges along the roadside whenever we drove past their lines. What constituted a good hedge? Why were some neat and others much more jumbled? I had an early, uneducated preference for the neat. Why were some bare at the base? Why did a few hedges have trees at intervals along their length?
I loved those lines in winter, dark streaks on the landscape, dividing up larger spaces, boxing in fields. I began to look out too for the way the sun catches the lichens on the bare branches and makes a surreal, sulphur-yellow glow. Sky blue, overwintering cereal green, lichen yellow: the bottom half of the colour wheel.
It was the humble lichen, with their shock of colour in a cold-palette landscape that made me begin to look for the details in the hedges, and see that these assemblies are so much richer than just the obvious structural species that formed them. When I started walking the local hedges in winter, when generally our plant life is in a quiet holding-pattern, I found there was so much lichen life extending in circles, forming crusts and cups on the bare exposed branches. Algae were there too and moss flared up the trunks in green rushes where the conditions of winter wet were right.
Lichens are so often overlooked. These complex organisms are mutualists: a hook up between a fungus and an algae and/or a cyanobacteria. The algae and cyanobacteria photosynthesise - in the partnership they stock the larder. The fungi, which need an external source of food, builds the larder they stock. It is this coming together of two or three organisms that fashions those colourful cups and crusts, fans and miniature forests that we see on stone and gravestones, gateposts and hedges.
Hedges are a living substrate, something for the lichens to grow upon. Lichens tell us a lot about where we live, the health of our environment and what we are doing to it. Lichens growing on twiggy hedges may better reflect current conditions, while their neighbours on stouter trunks deeper in the hedge tend to speak to past times. Lichen biology makes them inherently sensitive to pollution in the air, especially atmospheric nitrogen and sulphur dioxide. Lichens have no protective tissues and absorb such gases directly from the atmosphere. So when I looked, I found many, many nitrogen tolerant cushion Xanthoria spp coating on my local hedges, surrounding intensively farmed fields. If I was first taken in by their beauty, I saw how I could learn to read our hedges in fascinating and deeply informative ways. They are in fact helpful manuals to the current state of our countryside and the lichens they support are part of the lexicon.
https://www.nhm.ac.uk/discover/nature-and-pollution-what-lichens-tell-us-about-toxic-air.html
https://britishlichensociety.org.uk/learning/what-is-a-lichen