Drosera rotundifolia (Round-leaved sundew) - a species common to Ireland (source)

Irish Carnivorous Plants

Wildlife and Fauna


Most people associate the idea of carnivorous plants with some exotic location like a tropical rainforest. But in fact eleven species grow wild in the Irish countryside, ten of them native plants and one introduced.

There are three species of sundew. They're small red and green plants which get their name from hairy tentacles around the leaf margins that are coated in a transparent glue-like substance that glistens in the sun. When a small insect gets stuck in this the leaf curls up and the plant digests its prey. The round-leaved sundew is the commonest species and the long-leaved or greater sundew is the largest. The other one, the intermediate sundew, is a rarity confined to a few locations in the west of Ireland. They are bog plants and average about five insects or small spiders a month.

There are also three native species of butterwort. They don't have tentacles like the sundews, instead the surface of their flat, yellowish leaves is greasy, as if it had been coated in butter. Prey creatures get stuck on this and the leaf rolls up to digest them. The large-flowered butterwort has a fine spike of purple flowers in early summer and is only found in rocky uplands in Cork and Kerry. The common butterwort is similar but smaller and is commonest in rocky or boggy parts of the north-west. The pale butterwort has small pink flowers and is also found mainly in western counties.

The four species of bladderwort have a totally different hunting technique. They are small, free-floating water plants. They create a vacuum inside a digestive chamber or bladder. When something like a water flea swims past they spring open the door of the bladder, the vacuum sucks the prey in and the door shuts behind it. The whole process can take as little as 1000th of a second.

In 1906 pitcher plants from south eastern Canada were introduced into a bog in Co Roscommon and have established themselves in several other midland raised bogs since then. They have rather gaudy red, green and yellow leaves that form a conical cup or pitcher. This fills with a mixture of rain water and digestive juices and the plant then produces alluring scents to attract flying insects. When they land on the inside surface of the pitcher they are trapped by downward pointing hairs and the plant drugs them with narcotic gases. They end up drowning in the liquid at the base of the pitcher and being digested.

Two species of sundew are shown in the series and there is a short feature on the pitcher plants growing outside the Corlea Trackway Visitor Centre.


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Irish Plants in Episode Six

In episode six of the series, Dick visits Corlea Trackway Visitor Center where he does a short feature on two species of sundew common in Ireland.

Read more about episode six »