In late February I had a hip joint replaced, and then came lock-down: a combination that limited me, for a while, to tramping the streets of the town where I live. One of the joys of this has been getting to know the botanical life that lives in the gutter: clinging to walls, cracks in the pavement, rough ground and doorways. These are the backstreet habitats exploited by the nimble and exotic alike; places where newly arrived migrants rub shoulders with native lowlife, eking out a living just under the radar.

In March and early April there were the ’weeds’ such as thale cress, whitlowgrass and cornsalad – none of them very photogenic but still smart enough to flower and set seed before anyone noticed how ‘untidy’ they were. Many of these annuals are native plants, originally inhabitants of open ground that was probably scarce in the ‘wildwood’. Later they prospered and spread amongst crops in agricultural landscapes and yet more recently they have colonised the dry places and disturbed ground of our urban spaces.

Many new arrivals have simply scrambled over the garden gate – an ornamental quaking grass is well established in parts of Machynlleth. Similarly I have found pansies, snapdragons and two exotic bellflowers, as well as more culinary opportunists such as oregano, fennel and lemon balm, each decorating the gutters and walls of our streets. We can also thank gardeners for more notorious escapees such as rhododendron ponticum and Japanese knotweed. Rhododendron smothers whole hillsides not far from here and the knotweed is so prolific and tenacious that you can incur a hefty fine just for moving it from place to place.

Our flora has always been on the move. When the ice sheets and permafrost retreated northwards 12,000 years ago Britain was still joined to Europe and plants from the south and east were able to gradually colonise the warming ground. Later, humans started to move longer distances and plants went with them. Much of our arable flora, along with the wild ancestors of wheat, originated in the bone-dry grasslands of Turkey and the Middle East where their seeds mixed with the grains taken into cultivation. Until cleaning of cereal seeds became more efficient in the 19^th century wild flowers were unintentionally harvested and re-sown for centuries, alongside wheat, oats and barley. Ecologically life in the bare, well drained soil of the cereal fields was like Turkey revisited, so consequently they thrived. The patriotic red poppies of our cornfields and waysides were part of this ‘invasion’ and so are not in fact native but early colonists of our farming landscape. For the last 150 years or so this arable flora has been in steady decline with cornflowers, hairy mallow, weasel’s-snout and the rest almost extinguished by increasingly efficient farming methods.

A preferential class system extends into the classification of Britsh plants: 60 years ago it was simple and brutal – natives okay, the rest – beyond the pale. More recently this has been broadly stratified into natives, archaeophytes (established before 1500) and neophytes (arrivals since 1500), the last two together are defined as ‘aliens’. This often seems like a declining order of worth amongst field botanists, with natives as the most highly regarded. Delightfully some plants have the temerity to ignore the rules. The Welsh poppy is an outstanding example of a plant becoming downwardly mobile. It is still found as a scarce native plant in mountainous areas (including not far from here on Cader Idris) where it is revered by botanists. Unsurprisingly such an attractive plant was taken into cultivation and from there it absconded back into the wild, to inhabit walls and waysides. This same lovely plant now belongs to a much lower caste than its mountain relatives.

There is a glorious ‘anything goes/survival of the fittest’ feel to this guttersnipe community. Under-loved natives such as cats-ears, dog daisies and ferns burst out of the cracks and scuffed-up soil, taking their chance alongside newcomers like periwinkle, red valerian and purple toadflax. It is a hazardous existence, at least in this town, where the council deems all this effervescent beauty to be unruly and unregulated. They send in a man with a strimmer who, like a modern incarnation of the grim reaper, cuts many off in their prime and later administers a dose of glyphosate for good measure.

But these botanical riffraff are a resourceful and tenacious bunch; many of them will outlive us all, bursting through the cracks of Armageddon Street long after we have gone. During lock-down the only things growing on the streets of this town were in the gutter.