Species Profile and Threats Database

For information to assist proponents in referral, environmental assessments and compliance issues, refer to the Policy Statements and Guidelines (where available), the Conservation Advice (where available) or the Listing Advice (where available).
In addition, proponents and land managers should refer to the Recovery Plan (where available) or the Conservation Advice (where available) for recovery, mitigation and conservation information.

EPBC Act Listing Status Listed as Critically Endangered
Listing and Conservation Advices Commonwealth Listing Advice on Prasophyllum olidum (Pungent Leek-orchid) (Threatened Species Scientific Committee, 2001bg) [Listing Advice].
Recovery Plan Decision Recovery Plan required, this species had a recovery plan in force at the time the legislation provided for the Minister to decide whether or not to have a recovery plan (19/2/2007).
Adopted/Made Recovery Plans Flora Recovery Plan: Tasmanian Threatened Orchids 2006-2010 (Threatened Species Section (TSS), 2006a) [Recovery Plan].
Policy Statements and Guidelines Draft survey guidelines for Australia's threatened orchids (Department of the Environment, 2013b) [Admin Guideline].
Federal Register of
    Legislative Instruments
Declaration under s178, s181, and s183 of the Environment Protection and Biodiversity Conservation Act 1999 - List of threatened species, List of threatened ecological communities and List of threatening processes (Commonwealth of Australia, 2000) [Legislative Instrument].
Inclusion of species in the list of threatened species under section 178 of the Environment Protection and Biodiversity Conservation Act 1999 (05/10/2001) (Commonwealth of Australia, 2001c) [Legislative Instrument].
State Government
    Documents and Websites
TAS:Prasophyllum olidum (Pungent Leek-orchid): Species Management Profile for Tasmania's Threatened Species Link (Threatened Species Section (TSS), 2014ax) [State Action Plan].
TAS:Listing Statement Prasophyllum olidum (Threatened Species Unit (TSU), 2001d) [Information Sheet].
TAS:Flowering Times of Tasmanian Orchids: A Practical Guide for Field Botanists (Wapstra, M., N. Roberts, H. Wapstra & A. Wapstra, 2008) [Information Sheet].
State Listing Status
TAS: Listed as Endangered (Threatened Species Protection Act 1995 (Tasmania): September 2012 list)
Scientific name Prasophyllum olidum [64951]
Family Orchidaceae:Orchidales:Liliopsida:Magnoliophyta:Plantae
Species author D.L. Jones
Infraspecies author  
Reference Austral. Orchid Res. 3: 108 (1998)
Distribution map Species Distribution Map

This is an indicative distribution map of the present distribution of the species based on best available knowledge. See map caveat for more information.

Illustrations Google Images

Scientific name: Prasophyllum olidum

Common name: Pungent Leek-orchid

The Pungent Leek-orchid derives its name from the erect, hollow appearance of its leaves, which bear resemblance to a leek. Its scientific name, Prasophyllum olidum, comes from the latin word olidus, which means strongly fragrant. In fact the green to greenish-brown flowers emit a fragrance that it described as almost overpowering. The leaf of the Pungent Leek-orchid is green to yellowish-green with a pinkish red base. The free part is 12–22 cm long. The species flowers in November and December. During this period the plants are 35–60 cm tall. They have 10–30 flowers in a dense spike 6–12 cm long. The ovary is green. The flowers are 14–16 mm long and 7–9 mm wide. The lateral sepals are free throughout, parallel or slightly divergent. The petals are 7–9 mm long and 1 mm wide (Jones 1998d). The labellum is elliptical and abruptly contracted near the middle. It is abruptly recurved at right angles near the middle, then erect or shallowly recurved. The labellum has irregular margins and the shiny, fleshy green callus on the labellum is broadly channelled at the base and extends nearly to the labellum apex (TSU 2001d).

The Pungent Leek-orchid can be differentiated from the similiar species, Prasophyllum rostratum, by its stronger fragrance and thinner texture of the petals and sepals. The callus on the labellum of the Prasophyllum rostratum is thicker, almost bulbous (TSU 2001d).

The Pungent Leek-orchid is known from a single population spanning an area of 0.5 ha on the Campbell Town Golf Couse (Jones 1998, Jones et al. 1999, TSU 2001d).

There is only one known population of the Pungent Leek-orchid, with an estimated 200 plants. Extensive surveys in 1999 failed to locate any more populations. The population has been declining in numbers, however it is not known whether this is due to management practices or drought (TSU 2001d).

Campbell Town Golf Course monitoring report
The 2009 monitoring report found that the Pungent Leek-orchid numbers at Campbell Town Golf Course were significantly higher in 2009 than 2008, with 126 plants in 2009 compared to just 8 in 2008, again a presumed consequence of the higher winter rainfall experienced in 2009. The report also recomended monitoring be continued for the next five years (Schahinger 2009).

The Pungent Leek-orchid is found in relatively damp native grassland on sandy loam. It is found at an altitude of 200 m. It occurs in the driest regions of Tasmania, having only 500 mm of rain annually (Jones 1998, TSU 2001d).

The Pungent Leek-orchid reproduces via insect pollination. The labellum produces a vast quantity of nectar which is desirable to a variety of native insects including bees, wasps and beetles (TSU 2001d).

The main threat to the Pungent Leek-orchid is potential habitat destruction through agricultural practices. The restricted distribution and failure to locate more populations makes the chance of locating the species elsewhere unlikely. However, suitable potential habitat has been located but is under constant threat of destruction for agricultural purposes. Fertiliser application threatens all species of orchids which are naturally sensitive to fertilizer application. Ploughing is another habitat clearing process (TSU 2001d).

The Campbell Town Golf Club is privately owned, however a voluntary covenant and an associated management plan aims to protect threatened flora species occuring on the golf course. The site in which the Pungent Leek-orchid occurs has recently experienced dense growth of Kangaroo Grass (Themeda spp.), due to lack of use by golfers. Fire management of Kangaroo Grass may be appropriate (TSU 2001d).

Future threats include a change in water supply to the golf club. Cheaper water supplied from a local tertiary sewage plant is rich in phosphates which are deadly to Orchid tubers. Planting shrubs and trees for aesthetic reasons will alter the grassland environment near the Pungent Leek-orchid. The extremenly localised distribution of the species suggests extreme sensitivity to environmental conditions, hence any alterations, even minor ones, may adversly impact on the species (TSU 2001d).

The Flora Recovery Plan: Tasmanian Threatened Orchids 2006-2010 (TSS 2006a) was developed to address the threats facing 68 threatened orchid species in Tasmania. The overall objective of recovery is to minimise the probability of extinction in the wild of threatened orchid species listed on the Tasmanian TSP Act and the Commonwealth EPBC Act and to increase the probability of each taxon becoming self-sustaining in the long-term.

Within the life span of the plan (five years), the specific objectives for recovery for Tasmania's threatened orchids are:

  • Acquire accurate information for sound management decisions and conservation status assessments.
  • Ensure priority populations are managed appropriately and are securely protected.
  • Increase the number of known populations of threatened orchid taxa.
  • Raise public awareness of orchid conservation issues and develop mechanisms to encourage and coordinate community participation in orchid recovery programs.
  • Establish a network of government and non-government organisations and individuals that can provide input into recovery programs and undertake recovery actions.
  • Develop a better understanding of the life history and ecological requirements of threatened orchids in Tasmania.
  • Increase the size of priority populations in the wild.
  • Identify critical and potential habitat.
  • Establish a genetically representative ex situ collection of orchid taxa facing imminent extinction in the wild.

The following table lists known and perceived threats to this species. Threats are based on the International Union for Conservation of Nature and Natural Resources (IUCN) threat classification version 1.1.

Threat Class Threatening Species References
Agriculture and Aquaculture:Agriculture and Aquaculture:Land clearing, habitat fragmentation and/or habitat degradation Contributions to Tasmanian Orchidology 1-9. Australian Orchid Research. 3. (Jones, D.L., 1998d) [Journal].
Commonwealth Listing Advice on Prasophyllum olidum (Pungent Leek-orchid) (Threatened Species Scientific Committee, 2001bg) [Listing Advice].
Agriculture and Aquaculture:Livestock Farming and Grazing:Habitat loss and modification due to clearance of native vegetation and pasture improvements Contributions to Tasmanian Orchidology 1-9. Australian Orchid Research. 3. (Jones, D.L., 1998d) [Journal].
Ecosystem/Community Stresses:Indirect Ecosystem Effects:Restricted geographical distribution (area of occupancy and extent of occurrence) Commonwealth Listing Advice on Prasophyllum olidum (Pungent Leek-orchid) (Threatened Species Scientific Committee, 2001bg) [Listing Advice].
Species Stresses:Indirect Species Effects:Low numbers of individuals Contributions to Tasmanian Orchidology 1-9. Australian Orchid Research. 3. (Jones, D.L., 1998d) [Journal].
Commonwealth Listing Advice on Prasophyllum olidum (Pungent Leek-orchid) (Threatened Species Scientific Committee, 2001bg) [Listing Advice].

Jones, D.L. (1998d). Contributions to Tasmanian Orchidology 1-9. Australian Orchid Research. 3. Essendon, Victoria: Australian Orchid Foundation.

Jones, D.L., H. Wapstra, P. Tonelli & S. Harris (1999). The Orchids of Tasmania. Carlton South, Victoria: Melbourne University Press.

Schahinger, R. (2009). Prasophyllum incorrectum & Prasophyllum olidum at Campbell Town Golf Course: November 2009 monitoring report. Threatened Species Section. Tasmania: Department of Primary Industries, Parks, Water and Environment.

Threatened Species Section (TSS) (2006a). Flora Recovery Plan: Tasmanian Threatened Orchids 2006-2010. [Online]. Hobart, Tasmania: DPIWE. Available from:

Threatened Species Unit (TSU) (2001d). Listing Statement Prasophyllum olidum. [Online]. Tasmania: Department of Primary Industries, Water & Environment. Available from:$FILE/Prasophyllum%20olidum%20listing%20statement.pdf.

EPBC Act email updates can be received via the Communities for Communities newsletter and the EPBC Act newsletter.

This database is designed to provide statutory, biological and ecological information on species and ecological communities, migratory species, marine species, and species and species products subject to international trade and commercial use protected under the Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). It has been compiled from a range of sources including listing advice, recovery plans, published literature and individual experts. While reasonable efforts have been made to ensure the accuracy of the information, no guarantee is given, nor responsibility taken, by the Commonwealth for its accuracy, currency or completeness. The Commonwealth does not accept any responsibility for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the information contained in this database. The information contained in this database does not necessarily represent the views of the Commonwealth. This database is not intended to be a complete source of information on the matters it deals with. Individuals and organisations should consider all the available information, including that available from other sources, in deciding whether there is a need to make a referral or apply for a permit or exemption under the EPBC Act.

Citation: Department of the Environment (2014). Prasophyllum olidum in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: Accessed Tue, 29 Jul 2014 06:12:48 +1000.