About a century ago, Ireland's leading naturalist, Robert Lloyd Praeger, was asserting the island's uniqueness in nature, with plants and animals found nowhere else in the world. For Irish botany in particular, he sought a stature equal to Britain's.
Tramping the fields, bogs and islands, his mounting records of plants formed the basis of national biogeography, showing where native plants were growing and why. With information so hard won, he was inordinately cross about attempts to introduce species where they didn’t belong.
A most grievous example was the decision of a British army captain, a keen amateur lepidopterist, to plant land in Co Limerick with a thicket of alder buckthorn, sole native foodplant of the lovely, but scarce, yellow brimstone butterfly. It would serve, he hoped, ready-to-hatch pupae he had brought from England.
In an article in the Irish Naturalist, Praeger scorned this attempt at “forging nature’s signature”, a ringing phrase that has survived among his heirs in Ireland’s natural history.
Among them are members of the Dublin Naturalists’ Field Club (DNFC) of which Praeger was long a president. Its members have been responsible for publishing many authoritative field surveys, notably the exhaustive Flora of County Dublin, led by Declan Doogue and first published in 1998.
Since then, Ireland has seen a wave of wildflower planting by local authorities, schools and individual enthusiasts, much of it responding to the national campaign to check the decline of bumblebees and other pollinating insects.
Trinity debate
In central Dublin, for example, Trinity College dug up patches of manicured lawn flanking its entrance at College Green to replace them with miniature wildflower "meadows". Widely approved and admired by passers-by, they have now, however, been included in a gallery of plantings from Co Dublin deplored by the botanists of the DNFC.
A photograph of Trinity’s flowers is included in a DNFC “position paper” setting out “the case against ‘wildflower’ seed mixtures”. Its caption sees Trinity’s miniature meadows as mass planting of “eye-catching, fast-growing, quick-flowering plants, mixing yarrow, campion, poppy, oxeye daisy and more. “This grouping,” it asserts, “misrepresents the species assemblages that would occur in nature and does not meet the complex habitat requirements of threatened insects.”
Planting the wildflowers, said Trinity, was “part of the university’s response to Ireland’s biodiversity crisis”. It mixed native annuals and perennials to flower from spring to autumn “as a constant reminder of what nature looks like” and “to increase the range of plants available to pollinators”.
To the DNFC, however ,“simply introducing colourful flowers ... at best provides a short-term food supply for some common insects that are not threatened”.
The typical mix of plant species contained in “wildflower” seed packets, it says, “is never found growing together in the wild”. Natural habitats, formed by local conditions, grow the plants adapted to them and these colonise the ground by natural means. Conserving natural habitats should be the priority. And even mowing old lawns less often can allow native species already in the soil bank to flower and set seed.
Displaced natives
The club describes the long history of landscape change and upheaval in its soils that has lost natural habitats and flora across most of Ireland. Unravelling the impacts on rarer species and plant-insect partnerships is part of the job for plant ecologists working in habitat restoration.
These are often dismayed by the popular options of “wildflower” sowing that threaten or displace native plants with those grown from imported and genetically different seed.
Prof John Parnell, professor of systematic botany at Trinity and himself a member of the DNFC, explains the college’s intention in the College Green planting scheme. “We are not trying to emulate any natural species assemblage. What we are aiming to do, and have done, is to increase the biodiversity and resource available for pollinating and other insects: effectively this is a new form of gardening. The campus is currently being surveyed to assess its biodiversity and we will know more about its biodiversity then.”
Among other examples pictured in the DNFC paper is an “impossible assemblage” flowering colourfully on a roadside verge in Portrane, Co Dublin. The soil had traditionally grown the native prickly poppy, a rare species on sandy ground near the sea, now in serious decline from suburban sprawl.
Similar issues concern the Botanical Society of Britain and Ireland and are discussed at length on its website by Kevin Walker, its head of science. He accepts that the "huge amount" of sowing, mainly of European seed, will continue unabated ("even our mountaintops are not immune") .
Botanists, he makes clear, differ widely in their responses. “At one extreme,” he writes, is the traditional view that the seed sowing “muddies the waters of native distributions” and should be discouraged. But a minority, he grants, would welcome the restoration of floral diversity in adaptation to climate change.
Some restoration ecologists are ready to engage with “novel ecosystems” thrown up in the fast-changing world of the Anthropocene. Sowing masses of wildflowers expresses wide and active support for biodiversity.
For that, its random affronts to biogeography may be seen to be a price worth paying. But the protest from the DNFC may help to protect the fragments of surviving natural habitat from potentially destructive, if decorative, swathes of alien bouquets.
