Epilobium brunnescens is a flowering plant belonging to the willowherb genus Epilobium in the family Onagraceae. It is a small, creeping, perennial plant with white or pale pink flowers. It is native to New Zealand and south-east Australia and has been introduced to Northern Europe. Its common names include New Zealand willowherb in Great Britain and Ireland, creeping willowherb in New Zealand and bog willowherb for the Australian subspecies.
It is a low-growing, mat-forming plant with stems that trail along the ground, reaching 20 centimetres in length. The stems have two rows of tiny hairs and have roots at the nodes. The flowers have white or pale pink petals that are 2.5–4 millimetres in length. The leaves are rounded and are usually 3–7 millimetres long, sometimes reaching 10 millimetres. They are purplish below, have smooth or slightly toothed edges and have a 0.5–3 millimetre stalk.
Distribution and habitat
The species is widespread in New Zealand, occurring on North Island, South Island, Stewart Island, the Auckland Islands and the Campbell Islands as well as on the Australian possession of Macquarie Island. It grows in a variety of habitats, particularly open, shingly riverbeds in areas of high rainfall. Two subspecies are present in New Zealand: E. b. subsp. brunnescens which usually has nodding flowers and E. b. subsp. minutiflorum which usually has erect flowers.
The subspecies E. b. subsp. beaugleholei is restricted to a single site in Alpine National Park in eastern Victoria, south-east Australia. It grows on wet, mossy rocks close to a waterfall at an altitude of about 1320 metres. A survey in 2001 found only three patches of the plant, covering a total area of 1 m2. The subspecies is considered to be at high risk of extinction due to threats such as rock fall, drought, illegal collection and damage by visitors.
E. b. subsp. brunnescens has been introduced to Great Britain and Ireland where it was first recorded in 1904 in Craigmillar, Edinburgh. It spread rapidly from the 1930s onwards and is now widespread in northern and western areas where rainfall and humidity are higher. It has not yet spread to many parts of southern and central England and central Ireland. It occurs in various damp, open, gravelly or stony habitats including hillsides, stream banks, waste tips, stone walls, paths and railway sidings.
- Stace, Clive (2010) New Flora of the British Isles, 3rd edition, Cambridge University Press.
- New Zealand Plants: Epilobium brunnescens (Cockayne) P.H.Raven & Engelhorn. Accessed 14 April 2013.
- Carter, Oberon & Neville Walsh (2006) National Recovery Plan for the Bog Willow-herb Epilobium brunnescens subspecies beaugleholei, State of Victoria Department of Sustainability and Environment.
- Webb, D.A., Parnell, J. and Doogue, D. 1996. An Irish Flora. Dundalgan Press (W. Tempest)Ltd. Dundalk. ISBN 0-85221-131-7
- Poland, John & Eric Clement (2009) The Vegetative Key to the British Flora, Botanical Society of the British Isles.
- Flora of Australia Online: Epilobium brunnescens (Cockayne) P.H.Raven & Engelhorn subsp. brunnescens. Accessed 14 April 2013.
- Raven, Peter H. & Tamra Engelhorn (1971) New Taxa and New Combinations in Australasian Epilobium (Onagraceae), New Zealand Journal of Botany, 9 (2): 345-350.
- Kitchener J. D. & D. R. McKean (1998) Hybrids of Epilobium brunnescens (Cockayne) Raven & Englehorn (Onagraceae) and their occurrence in the British Isles, Watsonia, 22: 49-60.
- Online Atlas of the British & Irish Flora: Epilobium brunnescens (New Zealand Willowherb)
- Species Profile and Threats Database: Epilobium brunnescens subsp. beaugleholei — Bog Willow-herb