Lathraea squamaria | Toothwort | Slánú fiacal
- Plants grow to about 20 cm, and flower in
April and May.
- Only the flowering stem is seen above the ground, arising from a
perennial rhizome beneath the soil which parasitizes Hazel, Elm, Sycamore and
- Like other plants in the Broomrape family (Orobanchaceae) it lacks any green pigment.
- The creamy pink flowers are borne in a one sided spike. They are irregular, with a hairy calyx which has four lobes.
- The pink or purple corolla is tube-like and made up of four petals; they are arranged into an upper lip and a three-lobed lower lip.
- There are four stamens which grow out from the corolla, and a single style.
- There are no leaves on this plant, but instead small scales on the thick stem.
- The fruit is a capsule which contains many tiny seeds.
Toothwort’s closest relative Purple Toothwort (Lathraea clandestina) is not native in Ireland. Toothwort may be confused with Bird’s-nest Orchid (Neottia nidus-avis). Like Toothwort, Bird’s-nest Orchid grows in woodlands and flowers in early summer. It also lacks green pigmentation, but unlike Toothwort it is not a parasitic plant - instead it is a saprophytic plant (feeds on dead matter, e.g. decaying leaves on the woodland floor). Its flowers are light brown or golden in colour and have a different shape from the two lipped creamy pink flowers of Toothwort.
Toothwort grows in woodland habitats on moist rich soils. It is parasitic on the roots of Hazel and Sycamore, and apparently a range of other trees, and so will be found growing in close proximity to them.
The plants are pollinated by bumble bees and can produce copious seed. The seeds have elaiosomes, (fatty structures attached to the seeds) and are distributed by ants.
Many areas of woodland habitat in Ireland are under threat of changing management or abandonment, and tend to be quite small or fragmented. Plants are vulnerable to trampling by grazing animals, or may become crowded out by other plants, such as Brambles.
Toothwort may be found anywhere in Ireland but it is more common in the northern part of the country. It is an uncommon species, and may be considered an indicator of ancient woodland (Perrin and Daly 2010).
BSBI distribution map
Records submitted to Data Centre in 2023
The following map is interactive. If you would prefer to view it full screen then click here.
How can you help
Irish Species Project: If you have seen Toothwort or any of the species in the Irish Species Project, please fill out a recording form. It can be downloaded here, and you can also download the guidance document for detailed instructions (both also available at http://www.bsbi.org.uk/ireland.html).
You can also get in touch with your local BSBI Vice County Recorder via Maria Long, BSBI Irish Officer (email@example.com) or contact her if you have any questions.
Spring flowering plants project: Toothwort is also one of the species in our 2016 spring flowering plants project. All casual sightings submitted are very valuable.
Full list of species included in the spring flowering plants project:
- Common Dog-violet
- Early Dog-violet
- Early-purple Orchid
- Lady’s smock (Cuckooflower)
- Lesser Celandine
- Lords-and Ladies
- Wild Garlic
- Winter Heliotrope
- Wood Anemone
- Wood Sorrel
Irish Species Project: one of eight species chosen for the Irish Species Project, a two year recording effort by the Irish division of the Botanical Society of Britain and Ireland (BSBI). All eight species are thought to be declining, at least in parts of their range. Full list of eight species included in the Irish Species Project:
Moonwort (Botrychium lunaria), Cyperus Sedge (Carex pseudocyperus), Autumn Gentian (Gentianella amarella), Toothwort (Lathraea squamaria), Grass-of-Parnassus (Parnassia palustris), Cowslip (Primula veris), Common Wintergreen (Pyrola minor), Cranberry (Vaccinium oxycoccos)
Spring flowering plants project: this project is a collaboration between the National Biodiversity Data Centre and the BSBI. It is hoped we can collect valuable data to improve our knowledge of the current distribution of some common plants. All data will be fully validated by both partners before loading to Biodiversity Maps and being made available to the BSBI.
Parnell J. and Curtis T. (2012) Webb’s An Irish Flora. Cork: Cork University Press 8th ed.
Perrin, P.M. & Daly, O.H. (2010) A provisional inventory of ancient and long-established woodland in Ireland. Irish Wildlife Manuals, No. 46. National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland.
Preston C.D., Pearman D.A. and Dines T.D. (2002) New Atlas of the British and Irish Flora: An Atlas of the Vascular Plants of Britain, Ireland, the Isle of Man and the Channel Islands. Oxford: Oxford University Press
Rose F. and O’Reilly C. (2006) The Wild Flower Key: how to identify wild flowers, trees and shrubs in Britain and Ireland. London: Frederick Warne rev. ed.
Stace C. (2010) New Flora of the British Isles. Cambridge; New York : Cambridge University Press 2010 3rd ed.