The few weeks before the harvest are the best time to go out in search of a declining subset of our native flora – the arable ‘weeds’ for want of a better term. I find this term fascinating as it reflects their current status but ignores their origins – the majority of arable plants in the UK have been found by archaeologists to pre-date the commencement of agriculture in this country. The current catch-all term refers however to their ubiquity in our arable environment and many of the rarer species are now exclusively found on cultivated land.
Arable plants are a mixed bunch, but a number of characteristics tend to link them. The majority are annuals meaning that they can complete their life-cycle in a year. A small number are perennials, meaning the same plant survives from one year to the next. The annual life-cycle predisposes species towards success in an environment which, by the nature of modern agriculture, involves the wholesale destruction of the habitat on an annual or even bi-annual basis. The plants grow in spring, flower and rapidly set seed, often allowing a surprisingly stable annual population to persist in a particular location even though an individual plant will never survive from one year to the next. Taking these photographs, it was noticeable that particular species were prevalent within certain fields but absent from the majority of sites.
Another common characteristic of arable plants is that their seeds have a long dormancy period – this means that they can persist in the soil for long periods of time until conditions become suitable again. This is an obvious benefit for species which rely upon an outside influence to create the bare, open conditions they thrive in, or where frequent predictable disturbances make for a cyclical habitat suitability.
The original habitats of some of these species are probably lost from our current ecosystem dynamics, as many of our rarer species are now almost completely restricted to arable land where they find the conditions they require to persist. Many however can still be found in other modern habitats which receive frequent disturbance, such as coastal shingle or waste ground.
The eradication of competition on arable land is one of the stated objectives of modern agriculture and arable plants have decreased rapidly in the last century in response to the increased intensification of agriculture. Whilst their biology enabled them to deal well and indeed flourish in the conditions of annual disturbance, they are increasingly unable to deal with modern herbicides; with changes in the timing of cropping which prevents them from setting seed; with the superior ability of modern crops to respond to fertiliser enrichment and out-compete them; and with changes in drainage.
The common label of ‘arable weeds’ reflects not only their habitat, but their relationship to a particular group of people – the farmers who exploit the land. These widely-accepted terms always require consideration – one person’s weed is another person’s wildflower. These are ‘weeds’ in a similar way to the blase acceptance that foxes are ‘vermin’ – to label a fox as such is an understandable view if you keep poultry, raise pheasants or, at a stretch, farm sheep, but indefensible across arable swathes of the countryside or in semi-natural habitats. These arable plants are often beautiful examples of our native flora and many of the rarer species have little or no negative impact on the crops they share the fields with. So don’t be put off by the derogatory epithet – go out, seek and enjoy them! They are often the only flashes of wild nature left in an otherwise ecologically-inert arable landscape.