The Killarney fern (Trichomanes speciosum) was one of the most sought-after plants in Victorian times. The over-enthusiasm of Victorian horticulturalists contributed to its decline. Today the fern is a protected species. It is on the National Botanic Gardens' red list of endangered species and is also protected by the European Union under the "Habitats" directive. The Killarney fern is the largest of the European filmy-ferns, with fronds growing to more than 30 cm in length. Apart from its size, the ferns' distinctive feature is the tubular shape of its sporing structures, which give it its alternative name: "bristle fern."
The Marsh Saxifrage, known as "Moran reisc" in Irish, is also a protected species under the European Union's "Habitats" directive and on the National Botanic Gardens' red list of critically endangered species. The flowering plant is a perennial and produces small, attractive yellow flowers. In the past it grew in both lowland and upland locations but, according to the British Joint Nature Conservation Committee, it is now considered an upland species as its lowland habitats have been destroyed.
Known in Irish as "Croch an fhomhair," meadow saffron is another plant on the National Botanic Gardens' red list of critically endangered species. Most bloom in September and October, bursting with attractive lilac flowers. The plant is, however, poisonous. It can survive in a variety of acidic and alkaline soils, but prefers a well-drained, light soil.
Divided Sedge, known as "Cib ghabhlach" in Irish and "Carex divisa" in Latin, is now so rare in Ireland that it was thought to be extinct until rediscovered in the 1990s, say T. G. F. Curtis and R. A. Fitzgerald of the National Parks and Wildlife Service in Dublin. The plant is another of those on the red list of critically endangered species issued by the National Botanic Gardens. The perennial herb enjoys brackish, marshy conditions near the sea. It has two main locations in Ireland, according to the 1990 survey; two within 10 kilometers of each other in county Wexford and another on the river Barrow in county Kilkenny.
