Blue willow pea (Psoralea fleta)

Kingdom	Plantae
Phylum	Tracheophyta
Class	Magnoliopsida
Order	Fabales
Family	Fabaceae
Genus	Psoralea (1)
Size	Height: up to 6 m (2)

Classified as Vulnerable (VU) on the 1997 IUCN Red List of Threatened Plants (3).

The blue willow pea is a slender, willowy tree with drooping branches. Its scientific name fleta means ‘weeping’ in Latin (4), referring to the downhearted air bestowed by its sagging branches. Each greyish leaf of the blue willow pea is divided into one to three, thread-like leaflets (2) (4), and members of the genus Psoralea all have resinous, dark or transparent dots covering the leaves (5). At certain times of the year, blue to pale mauve flowers are borne on slender stems that, like the branches, hang towards the ground (4).

Endemic to the Cape Floristic Region, a ‘hot-spot’ of plant diversity in south-western South Africa. The blue willow pea is distributed from the Elandskloof Mountains to Bainskloof (2)

The blue willow pea grows on mountain fynbos, between 660 and 1,000 metres above sea level (2)

The delicate flowers of the blue willow pea appear from October until March (2). Little information is available regarding the biology of this species, but members of this genus are characterised by their strong scent (5), presumably to attract pollinating insects. The pods of Psoralea species, which develop following pollination and fertilisation, contain just one seed (5).

There is no information available indicating what specific threats the blue willow pea faces, but there are a number of threats impacting the habitat of the Cape Floristic Region. Around 30 percent of the natural habitat of the region is currently, (as of 2003), transformed by agriculture, urbanisation and invasive alien plants, and this amount is predicted to increase significantly within the next twenty years (6), particularly as Cape Town’s vast population is expected to double by the year 2025 (7).

The Cape Floristic Region contains nearly 9,000 plant species, most of which are found no where else in the world. This unique area is valued for its incredible diversity in plants, and thus there are a number of protected areas (8), and a number of conservation organisations are working to conserve this botanically rich habitat. Conservation actions include purchasing land to protect it from the threats of encroaching agriculture and urban development (9), the removal of alien plants, and the establishment of new protected areas (7); measures which should benefit populations of the vulnerable blue willow pea.

For further information on the Cape Floristic Region and its conservation see:

• Conservation International: Biodiversity Hotspots:
  www.biodiversityhotspots.org/xp/hotspots/cape_floristic

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact: arkive@wildscreen.org.uk

• Cape Floristic Region: an area occupying about 90,000 square kilometres in South Africa that contains an incredibly high diversity of plant species (around 8,700 species), of which 68 percent are found no where else.
• Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
• Fynbos: the natural shrubland vegetation occurring in the southwestern and southern Cape of South Africa, holding the greatest diversity of plant species in the world. Fynbos is characterised by tall shrubs with large leaves, heath-like shrubs, wiry reed-like plants, and bulbous herbs.
• Pollination: the transfer of pollen grains from the stamen (male part of a flower) to the stigma (female part of a flower) of a flowering plant. This usually leads to fertilisation, the development of seeds and, eventually, a new plant.

1. Catalogue of Life: 2007 Annual Checklist (February, 2008)
   http://www.catalogueoflife.org/
2. Goldblatt, P. and Manning, J. (2000) Cape Plants: A Conspectus of the Cape Flora of South Africa. National Botanical Institute of South Africa, Pretoria .
3. Walter, K.S. and Gillett, H.J. (1998) 1997 IUCN Red List of Threatened Plants. IUCN, Gland, Switzerland and Cambridge, UK.
4. Paterson-Jones, C. and Manning, J. (2007) Ecoguide Fynbos. Briza Publications, Pretoria, South Africa.
5. PlantZAfrica (February, 2008)
   http://www.plantzafrica.com/plantnop/psoraleapin.htm
6. Rouget, M., Richardson, D.M., Cowling, R.M., Lloyd, J.W. and Lombard, A.T. (2003) Current patterns of habitat transformation and future threats to biodiversity in terrestrial ecosystems of the Cape Floristic Region, South Africa. Biological Conservation, 112: 63 - 85.
7. Conservation International: Biodiversity Hotspots (February, 2008)
   http://www.biodiversityhotspots.org/xp/hotspots/cape_floristic/Pages/default.aspx
8. UNEP-WCMC: Cape Floral Protected Areas of South Africa (February, 2008)
   http://www.unep-wcmc.org/sites/wh/pdf/CAPE%20FLORAL%20REGION.pdf
9. Fauna and Flora International (February, 2008)
   http://www.fauna-flora.org/fynbos.php