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Slaty Leek Orchid - profile Scientific name: Prasophyllum fuscum   Conservation status in NSW: Critically Endangered National conservation status: Vulnerable Description An orchid to 45 cm tall with a single leaf to 40 cm long. Inflorescences have 10-30 moderately crowded flowers, which are greenish brown to reddish brown, and lightly scented. Dorsal sepals are up to 9.5 mm long and pointed. Lateral sepals are free and up to 10 mm long and are recurved, parallel, pointed. Petals are 7-7.5 mm long, projecting forward to spreading, pointed. The labellum (median petal) is 8-9 mm long and sharply curved backwards near the middle, constricted and ending in a relatively short midlobe, often slightly crinkled. The callus is shiny, prominently raised, with irregular margins, extending beyond the labellum bend onto the midlobe. Column wings are bright or pale pink. There has been previous confusion regarding the taxonomic status of this species, as it is very similar to P. uroglossum and P. pallens. Location and habitat Distribution  The type specimen is from "moist meadows towards the Georges River" in the Sydney area. The species is likely to be extinct from this area. Harden (1993) states that it is confined to the Blue Mountains area. However, some authorities believePrasophyllum species from this area are not P. fuscum, but an undescribed species. In addition, some authorities believe it is identical to P. uroglossum which occurs in the Wingecarribee area.   Habitat and ecology The total population, based on a single observation in 2007, is estimated to be approximately 25 mature individuals. Grows in moist heath, often along seepage lines. The known population grows in moist sandy soil over sandstone amongst sedges and grasses in an area that appears to be regularly slashed by the local council. Flowering does not necessarily occur every year, often skipping years. Although successful flowering and reproduction is likely to be dependent on favourable weather and habitat conditions, the factors which influence flowering behaviour are poorly understood. The seed is dust-like and is wind dispersed. Dies back after the flowering and fruiting phases and exist only as a dormant tuber for much of the year. Like most terrestrial orchids, the species is believed to be semi or fully dependent on a mycorrhizal symbiont. Dormant over summer and leaves emerge around April and flowering occurs from September to December. The response of this species to fire is unknown, however fire stimulation of flowering is common within the genus. Reproduction is by means of seed and probably to a lesser extent by vegetative reproduction. Flowers are not self-pollinating , as not all set seed and the perfume suggests an insect pollinator. The pollinator is unknown, but related species seem to be pollinated by a variety of thynnid wasps and perhaps hoverflies. It can be assumed that there is more than one pollinator species. The mature seeds senesce after seed dispersal in late December and January. The species is very similar to P. uroglossum but has a much shorter midlobe on the labellum and by having the callus extending well onto the midlobe. It has also been confused with P. pallens which can be distinguished by its paler-coloured flowers with a musty smell. Regional information This species is found in the following catchment management authority regions. Click on a region name to see more details about the distribution, vegetation types and habitat preference of the species in that region. Hawkesbury/Nepean Hunter/Central Rivers Sydney Metro   Threats Illegal collection by orchid enthusiasts. Habitat loss and degradation due to agriculture, mining, urban development, changed hydrological conditions and decreasing water quality of swamps through poulltion or siltation, and weed invasion. The very highly restricted distribution and extremely low number of mature individuals exposes the species to stochastic events. May be threatened by roadside maintenance activities, where these involve habitat disturbance and slashing during the season of active growth, flowering and fruiting. Recovery strategies Priority actions are the specific, practical things that must be done to recover a threatened species, population or ecological community. The Department of Environment and Conservation has identified 9 priority actions to help recover the Slaty Leek Orchid in New South Wales. What needs to be done to recover this species? Incorporate a suitable fire regime for the species into land management practices. Seek formal protection of all remaining areas of known habitat under conservation/management agreements. Clearly identify roadside sites and ensure that processes are in place to prevent these sites from being impacted by roadside maintenance works. Undertake surveys in known and potential habitat. References Copeland L.M. (2008) Clarification of the taxonomy, and a reassessment of the conservation status , of , P. uroglossumand P. pallens in NSW. Report to the NSW Scientific Committee, Sydney. Harden, G.J. (ed.) (1993) Flora of New South Wales Vol. 4. UNSW Press, Kensington, NSW. Jones D.L. (2006) A complete guide to native orchids of Australia including the Island Territories. Reed New Holland, Sydney.