The Burren Flora

When it comes to ecological wealth and diversity, the Burren has few parallels elsewhere in Ireland. Supporting an enormous diversity of species in its orchid-rich limestone grasslands, heaths and pavements, the Burren contains twelve Annex 1 habitats listed in the EU Habitats Directive.

In terms of flora, the Burren is especially rich: Webb and Scannell (1983) recorded a total of 635 species from the Burren hills (345 square km), a remarkable tally representing over 70% of Ireland's 900 native species in less than 0.5% of its area! A recent research project (Dunford, 2001) found 28 different species per square meter (averaged over 1,100 vegetation samples) in upland grasslands, with up to 45 species per square metre in some samples.

Though the Burren does contain some much sought after rarities, its real ecological distinction relates to the abundant presence of several species which elsewhere are of very limited distribution. In the Burren are found several hundred square kilometers of species-rich unimproved limestone grasslands, a precious resource by any standards.

Some particularly noteworthy features of the flora found in the Burren include the curious mixture of Arctic-Alpine and Mediterranean species, and calcicole (lime-loving) and calcifuge (lime-hating) species, as well as the wealth of orchids - 22 of Irelands 27 native orchid species are found in the region. The more interesting members of this rich flora are usually found on upland pastures, dominated by bare rock and thin, intermittent, rendzina soils, a highly stressful growing environment. A reflection of this is the very compact morphology or life form that many of these plants assume, and the high proportion of parasitic plants found among them.

An important factor contributing to the rich floral diversity of the Burren uplands is the traditional practice of grazing these uplands mainly in winter. This practice serves to remove potentially dominant grass and weed species, thus allowing the dormant herb flora sufficient light and resources to prosper over their flowering season, with little threat of being trampled by livestock.