Download Nature and Wildlife in Roscommon - The Heritage Council

Species-rich esker grassland. Photo by Caitriona Carlin
Early purple orchid
26
esKers
Eskers are glacial features composed of narrow ridges of
sand and gravel that wind their way through landscapes.
Melt water streams running in a tunnel beneath melting
glacial ice deposited the sand and gravel as ice sheets
started to wax and wane at the end of the last Ice Age. There
are several eskers in south Roscommon.
Eskers are important because of their cultural,
geological and natural heritage value. The dry, well-draining
soil of eskers provides a habitat for many rare plants and
for species-rich dry calcareous grassland. This grassland is
also considered as a priority habitat for nature conservation
within the European Union. Eskers often have native
woodland growing on them and are often associated with
other habitats such as raised bogs and fens.
The esker system at Castlesampson, a Coillte property,
is a particularly fine example. The importance of the site
lies in its almost intact structure, something that is very
rare for Irish eskers, and the species-rich dry calcareous
grassland present.
Eskers contain a wide variety of plant species including
blue fleabane, mountain everlasting, carline thistle, hedge
bedstraw, early-purple orchid and fragrant orchid. Eskers
are also important areas for butterflies including the Small
blue and Dingy skipper, and birds such as the sand martin.