Round-leaved Sundew

Appearance

The leaves of the common sundew are arranged in a basal rosette. The narrow, hairy, 1.3-to-5.0-centimetre long petioles support 4-to-10-millimetre long laminae. The upper surface of the lamina is densely covered with red glandular hairs that secrete a sticky mucilage.

A typical plant has a diameter of around 3 to 5 centimetres, with a 5-to-25-centimetre tall inflorescence. The flowers grow on one side of a single slender, hairless stalk that emanates from the centre of the leaf rosette. White or pink in colour, the five-petalled flowers produce 1.0-to-1.5-millimetre, light brown, slender, tapered seeds.

In the winter, "D. rotundifolia" produces a hibernaculum to survive the cold conditions. This consists of a bud of tightly curled leaves at ground level.

Distribution

In North America, the common sundew is found in all parts of Canada except the Canadian Prairies and the tundra regions, southern Alaska, the Pacific Northwest, and along the Appalachian Mountains south to Georgia and Louisiana.

It is found in much of Europe, including the British Isles, most of France, the Benelux nations, Germany, Denmark, Switzerland, Czech Republic, Poland, Belarus, the Baltic countries, Sweden and Finland, as well as northern portions of Portugal, Spain, Romania and in Iceland and southern regions of Norway and Greenland. It is infrequent in Austria and Hungary, and some populations are scattered around the Balkans.

In Britain, this is the most common form of sundew and it can be found on Exmoor, Dartmoor, Sedgemoor, the Lake District, Shropshire, and Pennines in Scotland, among other places. It is usually found in bogs, marshes and in hollows or corries on the sides of mountains. It is the county flower of Shropshire.

In Asia, it is found across Siberia and Japan, as well as parts of Turkey, the Caucasus region, the Kamchatka Peninsula and southern parts of Korea. Populations can also be found on the island of New Guinea.

Status

The round-leaved sundew is classified as Least Concern in the IUCN red list.

In North America, it is considered endangered in the US states of Illinois and Iowa, exploitably vulnerable in New York, and threatened in Tennessee.

Habitat

The common sundew thrives in wetlands such as marshes and fens. It is also found in wet stands of black spruce, "Sphagnum" bogs, silty and boggy shorelines and wet sands. It prefers open, sunny or partly sunny habitats.