Epilobium hirsutum

Description

It is a tall, perennial plant, reaching up to 2 metres in height. The robust stems are profusely hairy with soft spreading hairs. The hairy leaves are 2–12 cm long and 0.5–3.5 cm wide. They are long and thin and are widest below the middle. They have sharply toothed edges and no stalk. The large flowers have four notched petals. These are purple-pink and are usually 10–16 mm long. There are 8 stamens. The stigma is white and has four lobes. The sepals are green.

It is relatively easy to distinguish from similar species at least in much of its European range, where its flowers are among species of its genus present there.

Distribution and habitat

The native range of the species includes North Africa, most of Europe up to southern Sweden, and parts of Asia. It is absent from much of Scandinavia and north-west Scotland. It has been introduced to North America and Australia.

It typically grows in wet or damp habitats without dense tree-cover up to 2,500 metres above sea-level. Common habitats include marshland and the banks of rivers and streams. It also occurs in anthropogenic contexts such as wet ditches and in general in places rich in nitrates. It flowers from June to September, with a peak in July and August.

Ecology

Epilobium hirsutum inhabits damp and waste places, river-sides and ditches.

The flowers are visited by many types of insects, and can be characterized by a generalized pollination syndrome. A number of insects feed on the leaves including the elephant hawkmoth, Deilephila elpenor.

Trichomes

The plant shows glandular trichomes. They are unicellular, without a specialized basal cell. They have a cutinized cell wall and a protruding pore on the top. The upper part of the trichome cell contains flavonoids, e.g. quercitrin and myricitrin.

References

Bibliography

• Blamey, Marjorie & Grey-Wilson, Christopher (2003) Cassell's Wild Flowers of Britain and Northern Europe, Cassell, London.
• Press, J. R.; Sutton, D. A. & Tebbs, B. M. (1981) Field Guide to the Wild Flowers of Britain, Reader's Digest, London.
• Tutin, T. G. et al. (1968) Flora Europaea, Volume 2. Cambridge University Press.

References

1. "''Epilobium hirsutum'' L.".
2. (2006). "Non-native Freshwater Plants: Hairy Willow-Herb". Washington State Department of Ecology.
3. (2003). "Wild flowers of Britain and Ireland: The Complete Guide to the British and Irish Flora.". A & C Black.
4. [[Martin, W. Keble]] 1965. ''The New Concise British Flora in Colour''; with nomenclature edited and revised by Douglas H. Kent and foreword by The Duke of Edinburgh. London: Book Club Associates by arrangement with Ebury Press/ Michael Joseph (1982)
5. Stace, C. A.. (2010). "New Flora of the British Isles". Cambridge University Press.
6. (1997). "Rosendunört, Epilobium hirsutum". Naturhistoriska riksmuseet.
7. (2015). "Competition for pollinators and intra-communal spectral dissimilarity of flowers". Plant Biology.
8. Webb, D.A., Parnell, J. and Doogue, D. 1996. ''An Irish Flora''. Dundalgan Press (W.Tempest) Ltd. Dundalk. {{ISBN. 0-85221-131-7
9. (2011). "Morphology and glandular activity of unicellular trichomes of Epilobium hirsutum". Biologia Plantarum.