Northern Ireland's Priority Species

Geranium sylvaticum – wood crane's-bill

 
Geranium sylvaticum

Geranium sylvaticum L.
Family: Geraniaceae

This wild geranium has a very restricted range as a native in Ireland, being confined to hazel scrub, lightly shaded woodland or woodland margins and meadows about Glenarm, County Antrim. The leaves are deeply-lobed on long stalks; the flowers are mauve in colour.

In brief

  • Restricted in Ireland to a small area between Larne and Glenarm, County Antrim
  • The earliest County Antrim record of this plant dates from 1887
  • Found in or round the margins of woodland or scrub along the basaltic scarp
  • Best seen when in flower (June – July)
  • The entire Irish native population lies within Northern Ireland
  • Threatened by scrub removal.

Species description
An herbaceous perennial geranium with deeply-lobed leaves on long stalks; the flowers are mauve in colour.

Life cycle
The plant is a perennial, herbaceous species, spreading locally by its rhizome; longer-distance dispersal is by seed, but there is no evidence now of any such spread of the plant within Northern Ireland. Flowers are normally hermaphrodite, but with male and female stages: this is a device which inhibits self-fertilisation. Pollination is by insects. Female-only flowers, on separate plants from hermaphrodite flowers, and flowers in which there are no separate male and female stages are known from studies on populations outside Ireland, but no data is available for Irish plants.

Similar species
Similar to meadow crane’s-bill (Geranium pratense), but with smaller flowers of a less intense blue. In the wild in Ireland these two species do not grow together.

How to see this species
The plant is known from post-1970 reports at four sites of which one is the Ulster Wildlife Trust Nature Reserve at Feystown where the plant is easily visible from the public road. Relevant access permissions should always be sought prior to visiting any site.

Current status
Found in hazel scrub or woodland margins in and round Glenarm, County Antrim. The plant is known from post-1970 reports at six sites (three sites post-1986), all within two contiguous 10x10 km grid squares, of which one site is the Ulster Wildlife Trust Nature Reserve at Feystown and another is an Area of Special Scientific Interest (ASSI). The most southerly site is at Killyglen, north of Larne, where it was last seen in 1971. Some old (1878 and 1937) records suggest it may once have been present in an additional two 10x10 km grid squares in the Glenarm district. The species is protected in Northern Ireland under the Wildlife Order (NI) 1985.

Why is this species a priority in Northern Ireland?

  • It is rare and the entire Irish population lies within Northern Ireland
  • It is classified as a vulnerable species in the Irish Red Data Book for Vascular plants.

Threats/Causes of decline
The principal threat is woodland or scrub clearance.

There has been an apparent decline from four to two 10x10 km squares since 1937, and an apparent loss of about four sites up to the present. These losses may be a result of under-recording, a lack of visits to old sites or a misinterpretation of older records.

Conservation of this species

Current action
There is a Northern Ireland Species Action Plan which was published in 2005.

  • One of the three post-1986 populations of wood crane’s-bill is in Glenarm Wood ASSI
  • It occurs in Feystown Nature Reserve, managed by the Ulster Wildlife Trust
  • Survey and monitoring work is carried out by the Ulster Wildlife Trust on Feystown Nature Reserve and by EHS at Glenarm Woods ASSI
  • Implementation of the Northern Ireland Habitat Action Plans for Mixed Ashwoods and Lowland Meadow.

Proposed objectives/actions

  • Maintain the current population of wood crane’s-bill at three sites
  • Maintain the current range of wood crane’s-bill at two 10x10 km squares
  • By 2015, increase the number of wood crane’s-bill populations to five sites
  • By 2015, increase the range of wood crane’s-bill to four 10x10 km squares.

What you can do
There is a number of sites where this species has not been seen since the 1970s or earlier. Examination of these sites to refind the plant would be valuable. Send records to The Botanical Society of the British Isles, c/o Department of Botany, National Museums Northern Ireland, 153 Bangor Road, Cultra, Co. Down, BT18 0EU or CEDaR, National Museums Northern Ireland, 153 Bangor Road, Cultra, Co. Down, BT18 0EU. Tel: 028 9039 5256, cedar.info [at] nmni.com.

Further information

Links
The Wildlife (Northern Ireland) Order 1985

The Ulster Wildlife Trust Reserve at Feystown

Flora of Northern Ireland

Northern Ireland Species Action Plan for Woodcranesbill

Northern Ireland Habitat Action Plans

Glenarm Woods ASSI

Feystown ASSI

Literature
Beesley, S. (2006). County Antrim Scarce, Rare & Extinct Vascular Plant Register. Ulster Museum. Belfast.

Curtis, T.G.F. and McGough, H.N (1988). The Irish Red Data Book – 1 Vascular Plants. Stationery Office, Dublin.

Hackney, P. (1992). Stewart & Corry’s Flora of the North-east of Ireland, 3rd edn. Institute of Irish Studies, Belfast.

Text written by:
Paul Hackney

iNaturalist: Species account : iNaturalist World Species Observations database