The crown jewels of our botanical heritage, Important Plant Areas (IPAs) shelter rare and varied species and habitats. Valued internationally for their exceptional plant populations, IPAs are now being recognized worldwide in a programme led by the plant conservation charity Plantlife (see pp.2445). In the UK, 150 IPAs have already been identified, including the following five.
1. Cairngorms, Scotland
At more than 1,220m high, the Cairngorms are the tallest mountains in the British Isles. Their height and distance from the sea produces low winter temperatures, encouraging the most arctic vegetation found anywhere in the country. Many arctic-alpines flourish here, such as woolly willow (Salix lanata) and the highly rare alpine fleabane (Erigeron borealis). Thanks to snow-beds lying late on the slopes, the Cairngorms also shelter many important mosses and liverworts.
2. Yorkshire Dales, England
The Great Scar Limestone so redolent of the Dales was laid down on seabeds some 300 million years ago. The characteristic ridged texture of today’s limestone pavements was formed during the last Ice Age, c.2.58 million years ago, when glaciers scraped away the surface of the seabed, exposing the natural joints in the underlying rock, which was then eroded by slightly acidic rain. The thin soils covering the rock today are home to a rich diversity of lime-loving grasses, ferns and wildflowers for which the limestone country of the Dales is justly renowned.
3. Ranscombe Farm, England
Famous for its rare wildflowers, such as lady orchid (Orchis purpurea), Ranscombe Farm is Plantlife’s largest English nature reserve, covering more than 250 hectares. Recently declared a country park, it includes some of our richest arable habitats, extensive ancient woodlands and fragments of chalk grassland. Much of the reserve lies within the Cobham Woods Site of Special Scientific Interest, while the whole farm forms part of the Kent Downs Area of Outstanding Natural Beauty.
4. Gower Peninsula, Wales
From limestone cliffs to dune grasslands, from open moorlands to ash woodlands – there is something here for every plant lover. The cliffs are home to several specialized species that can survive sea winds and salt spray, such as yellow whitlowgrass (Draba aizoides) and goldilocks aster (Aster linosyris), while the dune grasslands shelter more than 250 species of flowering plant, including the rare fen orchid (Liparis loeselii). Gowers extensive woodlands, too, offer spectacular displays of wildflowers.
5. Upper Lough Erne, Ireland
A large freshwater system formed from a series of flooded mounds in the River Erne, the Upper Lough is a complex of islands, bays and lakes bordered by damp pastures, fens and reed swamps, as well as ample alder, willow and oak forests. The surrounding parkland is renowned for its ancient trees and associated rare lichens.