The following article written by Robert and Rosalie Lawrence is from the Volume 37 No 9 October 2013 Journal of the Native Orchid Society of South Australia
Orchids and the concrete jungle that makes up a city don’t seem together, particularly the terrestrial orchids. Yet in the heart of one of the world’s most well known capital cities such an orchid was found. On the 19th July 2013, the Telegraph reported that botanists from the Natural History Museum had found in the middle of London a white helleborine orchid (Cephalanthera damasonium) which had not been seen in that region since 1900. It was found in the Queen’s backyard, Buckingham Palace. Despite the building, demolishing, rebuilding, bombing and rebuilding that has been going on for the last 400 years, here is an orchid which has survived to surprise the botanist. (For details see Long Lost orchid found in Buckingham Palace Garden)
It is always heartening to hear good news about orchids but here in Adelaide we have our own encouraging story. Settlement in Adelaide is not as long as in London by a long shot but in our own short time we have managed to clear and cover some very good land with concrete and bitumen. The result has been that much of our native flora has been lost with many of our orchid species being the first to disappear.
In recent years effort has been made to bring back the bush with revegetation projects. This work has not tended to involve the orchids, the work of Heather Whiting and her team of volunteers at Vale Park being an exception. Consequently, any orchids found on such sites tend to be the more robust species principally Pterostylis pedunculata, Microtis sp. and in some cases Linguella sp.
Finding anything else will always be special; but that is what has happened at site where a Shell petrol station stood for decades on the corner of Portrush and Greenhill Roads. After the demolition of the service station the site was an area of bare clay for about a decade. Then in 2003, work began on restoring native vegetation incorporating a mini wetland in an area of 2,000 square metres that was given the name Linden “Bush Garden”. Indigenous flora was sourced from the local region and the site has been kept meticulously weed-free by dedicated workers.
Originally 60 local species were planted with several other species arriving by themselves. Among the latter group are five species of orchids. These include a Microtis species and Pterostylis pedunculata, but the other three are more surprizing – Arachnorchis tentaculata, a small blue-flowered Thelymitra species and a Caladenia (syn Petalochilus) species. How they came to be there is a mystery. The long term viability of them will depend upon the continued maintenance of this unique site.
The City of Burnside should be congratulated both for its foresight and initiative as well as its ongoing support of this project.
Natural regeneration at Linden Gardens includes three plants of Arachnorchis tentaculata (King spider Orchid) that are understood to have flowered for the first time this year (2013). The buildings of the council chambers can be seen in the background.
Again this month was a varied selection of species with Pauline Myers’ Caladenia chapmanii (WA), Claire Chesson’s Thelymitra rubra, Jenny Pauley’s hybrid of Arachnorchis brumalis x conferta, David Hirst’s Caladenia discoidea and the winning entry, Rosalie Lawrence’s Diuris brevifolia.
This strikingly yellow flowered donkey orchid endemic to South Australia is listed as Endangered. Its range was once quite widespread in the southern Adelaide Mt Lofty Range region but now it is now restricted to pockets on the Fleurieu Peninsula and western Kangaroo Island in Heathy Woodland, Wetland and Riparian habitats.
There is interest today in cultivating orchids for conservation or ex situ conservation. With the reduced range of this species, can it be cultivated and thus continue to ensure its survival as a species? Some sources seem to suggest that it is an easy plant to cultivate, and some Diuris are easier than others, but Les Nesbitt points out that he has some plants from a rescue dig several years ago and that they have not multiplied very much in that time. This suggests that they may be dependent on a specific fungi. Though it has not been hugely successful in cultivation, it is worth noting that it has been used to produce hybrids with several other Diuris.
Reference
Bates, R. J. (2011) South Australia’s Native Orchids NOSSA DVD, Adelaide
Nesbitt, L personal communications
Adelaide and Mount Lofty Ranges South Australia Threatened Species Profile Fact Sheet – Diuris brevifolia
Sometimes a particular species of orchid is said to be rare or endangered, for instance Thelymitra circumsepta* is listed as endangered in South Australia but has no listing federally whilst the endemic Prasophyllym murfetii* is listed as Critically Endangered federally but only Endangered in South Australia.
Prasophyllum murfettii (Denzel’s Leek Orchid)
What do these listings mean and why are they different for the same species?
What are the Conservation Categories?
Conservation listing by governments gives species a legal status, which can then be used to determine the type of consideration to be given to individual species in decision-making processes for species conservation.
In South Australia, the two main legislations affecting native orchids are the state National Parks and Wildlife Act 1972 (NPW) and the national Environmental Protection and Biodiversity Conservation Act 1999 (EPB). There is also the International Union for Conservation of Nature (IUCN) Red List which is used for international treaties. Each has their own set of categories resulting in terms with slightly different meanings.
The IUCN classification is quite detailed but in summary the conservation status used are
Extinct – not seen for fifty years or despite intensive searching not seen at a previously known site
Extinct in the Wild – no natural populations exist; only surviving in cultivation
Critically Endangered – known only from a single non-viable population
Endangered – in danger of extinction unless the factors causing decline are arrested
Vulnerable – likely to become endangered if the only large populations is wiped out for whatever reason
Near Threatened – close to qualifying or likely to qualify for a threatened category in the near future
Least Concern
Data Deficient
Not Evaluated
The Australian Federal government, under Section 179 of the EPBC Act, has six categories
Extinct – no reasonable doubt that the species has died out
Extinct in the Wild – no natural population existing, surviving in cultivation
Critically Endangered – faces an extremely high risk of extinction in the wild in the immediate future
Endangered – faces a very high risk of extinction in the wild in the near future
Vulnerable – faces a high risk of extinction in the wild in the medium term future
Conservation Dependent – if the cessation of a specific conservation program ceased the species could become vulnerable, endangered or critically endangered
South Australia uses three categories based on the categories from the IUCN Red List Categories and Criteria.
Endangered (Schedule 7) – includes Critically Endangered Extinct in the Wild and Extinct
Vulnerable (Schedule 8)
Rare (Schedule 9) – this is a South Australian term not recognised elsewhere but the criteria are consistent with the IUCN Near Threatened category and refers to uncommon species that are naturally limited in location or are in decline. Hence it is possible for a species to be common interstate but threatened in South Australia, for example Anzybas unguiculatus* is rated rare.
Anzybas unguiculatus (Little Pelican or Cherry Helmet Orchids)
Another term that is frequently used is Threatened. For the IUCN Threatened encompasses the three categories of Critically Endangered, Endangered and Vulnerable. It means that a species rated as threatened with extinction under these three categories may have different degrees of threat – note the adjectives in the IUCN definitions above. This serves as a guideline for its usage in South Australia. It should also be noted that Threatened and Rare are not interchangeable but a species rated Rare may be threatened by outside influences.
There is another level of conservation which is the regional status. This level does not have any legal standing but it is helpful in managing the species. The IUCN Red List Categories and Criteria are used to assign a regional conservation status. This is helpful in managing species at this level.
Why does a species have different Conservation Categories?
Looking through Part Two of South Australia’s Native Orchids 2011, it is not uncommon to find a species with two different conservation statuses. It is not surprising when they have the same status eg Arachnorchis behrii* is rated Endangered both state and nationally but why are the others different? Some of this is due to the different number of categories – six federally but only three at the state level so Diplodium bryophilum* is nationally Critically Endangered but only Endangered in South Australia as there is no critically Endangered category. Others have a state status but no national status, for example the endemic Diuris brevifolia* is rated Endangered. Curiously there are no endemic species with the combination of a national status but no state status, although there are five non-endemic species found in South Australia that do have this combination.
Diuris brevifolia (Late Donkey Orchid)
This comes about because there are two different bodies determining the statuses through two very different processes.
Nationally under the EPBC Act any individual can nominate a species which is assessed by the Threatened Species Scientific Committee, put out for public comment, changes adjusted as necessary and then the recommendations are passed onto the Minister who approves or rejects the nomination.
In South Australia, DEWNR (Department Environment Water and Natural Resources) initiates the process by asking the experts, compiling data, holding workshops with the experts. A report is written for the National Parks and Wildlife Council outlining the changes under the NPW Threatened Species Schedules. Once the changes are approved, it is sent to the Minister for approval before being released for public comment. After any necessary adjustments the report is then sent to the South Australian Parliamentary Cabinet for final approval.
Both processes check the species under consideration against the IUCN criteria.
How many South Australian orchids are under threat?
On 22nd July 2014, Doug Bickerton presented a talk at the Native Orchid Society on the conservation status of South Australian orchids. The comparison between the State and Federal listings was as follows:
Number of Orchids with a Conservation Status under the NPW Act (State)
77 species Endangered
33 species Vulnerable
32 species Rare
A total of 142 species or 49% of all South Australian orchids are recognised to be under threat.
Number of Orchids with a Conservation Status under the EPBC Act (Federal)
4 Critically Endangered
22 Endangered
19 Vulnerable
A total of 45 species for the State have a Federal government legal conservation status.
The fact that one authority recognises a species and the other authority does not doesn’t mitigate against the seriousness of the threat to that species. The fact that a species does not have a conservation status from either authority does not mean that it is not under threat. It could still be in danger of extinction.
Cryptostylis subulata (Moose Orchid) State Conservation Status: Vulnerable National Conservation Status: not listed
Currently in South Australian there is a State-wide assessment underway and the results will be published in 2016.
This article was inspired and is based upon notes taken from a talk given by Doug Bickerton in 2014 at the Native Orchid Society of South Australia. I would like to thank Thelma Bridle, Conservation Officer, Native Orchid Society of South Australia, for her help.
*Based on information found in South Australia’s Native Orchids 2011
IUCN RED LIST CATEGORIES AND CRITERIA Version 3.1 Second edition Prepared by the IUCN Species Survival Commission As approved by the 51st meeting of the IUCN Council Gland, Switzerland 9 February 2000
The short answer is very little to none at all. As long as there is some organic matter in the soil mix terrestrial orchids will grow and flower without added fertiliser.
For fungus dependent orchids, such as Caladenia, a fresh layer of leaf litter added in summer to the top of the pot is all that is required. These orchids are seldom repotted.
Growers who show their non fungus dependent orchid plants for judging want strong superior plants. They add a pinch of blood & bone fertilizer to each pot during the annual summer repotting. Vigorous orchids like the colony forming greenhoods will respond to weak foliar feeding in the early growth stages, (April to July). If fertilizing is overdone the plants can burn or produce multiple flowers that grow into one another and ruin the spectacle of flowers.
Other factors are more important than fertilizer. Strong light in winter, constantly moist potting mix, excellent drainage, good air movement and a pest free environment are more important.
Thelymitra (Sun Orchids) in cultivationCaladenia latifolia in cultivationDiplodium robustum – one of the cauline greenhoods
With the development of cities here in Australia, many of our orchids were lost as habitat was cleared and the newly arrived settlers built houses and reconstructed the gardens they knew from the Old World; but the odd pocket of native bushland has survived. Cemeteries and golf courses have often been the only refuge for remnant bushland. One such refuge has been The Pinery, Grange Golf Club, the only known location of Oligochaetochilus arenicola (syn. Pterostylis arenicola) on the Adelaide Plains. In the National Parks and Wildlife Act, this orchid is scheduled as vulnerable. The Golf Club left this site intact and has been supportive of the conservation efforts of the Threatened Plant Action Group who in turn have received assistance from the Native Orchid Society of SA and the Natural Resources Adelaide and Mt Lofty Ranges.
Typical of the rufushoods, this Oligochaetochilus arenicola shows the sencesing leaves, pendent petals and hairs on the labellum. Photographer: H Lawrence
Below is a media release from the Natural Resources, Adelaide and Mt Lofty Ranges
Orchids come in ‘under par’ at Grange Golf course
News release
30 September 2015
A tiny remnant population of rare orchids which survives in a patch of bush on Grange Golf Course has increased 50% since last year, according to a new survey.
The survey conducted this month found 1200 individuals of the Sandhill Greenhood Orchid (Pterostyllis arenicola), a nationally threatened species which is considered critically endangered in the Adelaide and Mt Lofty Ranges region.
When surveys began 20 years ago, only about 100 plants survived at this site. But the latest survey has revealed the population is steadily increasing
The orchid comeback is thanks to decades of care by four groups involved with the annual survey: the Threatened Plant Action Group, the Native Orchid Society of SA, Natural Resources Adelaide and Mt Lofty Ranges, and with support from the Grange Golf Club.
The tiny fragment of native pine bushland in the middle of Grange Golf Course is one of the only known locations of this species within the entire Adelaide and Mt Lofty Ranges region, with other small populations known from near Wellington and Tailem Bend.
The orchid grows 10cm-25 cm high and produces hood-shaped flowers that are green and brown or red-brown with white markings. Most species of orchid flower for only a short period and for the Sandhill Greenhood, it will flower only for the next few weeks.
Grange Golf Course just happens to provide ideal conditions for the plant: red sandy soils and an over-story of native cypress pine trees.
Dedicated project partners have tackled the main threat to orchids – suffocation by Perennial Veldt Grass and Soursob weeds – through years of patient hand weeding.
The orchid comeback is a great success story of collaboration across the community to save one of our state’s tiny floral gems.
As a demonstration of nature’s interdependence, conserving the Sandhill Greenhood also means conserving a particular mycorrhizal fungus that must be in the soil for Sandhill Greenhood seeds to germinate. In addition, the flowers must be pollinated by a particular type of insect, the fungus gnat. The gnat is attracted by the orchid’s pheromones and tries to mate with the flower, only to find itself loaded up with a packet of pollen which it then transfers to the next flower as it continues its romantic adventures.
While the survey results are good news, the Sandhill Greenhood population is still precariously small, and it is hoped that as the population grows, so do the options to secure the species into the future.
South Australia has over 260 species of orchids, including 50 species of greenhood.
Five photos were entered for the September competition and there was a draw, Pauline Meyers’ flower of a plant from the Caladenia hueguelii complex from Western Australia and Jill McPherson’s Plumatichilos sp. Woodland Bearded Greenhood from Scott Creek Conservation Park. The other three by Chris Davey were photographed on Yorke Peninsula (see Letter to the Editor in this September Journal).
As winners they showcase the great diversity that are found in our Australian terrestrial orchids.
Plumatichilos belongs to the greenhoods but the features that set it apart from the other greenhoods are the long thin bristled labellum, the galea pinched in the middle resulting in two openings and the rosette of leaves growing a short way up the stem. Nationally there are thought to be several species but only a small handful have been named. In South Australia, there may be a few distinct species but currently they are usually identified with a phrase name such as Plumatichilos sp Woodland Bearded Greenhood.
Mainly flowering in spring the flowers of the Caladenia huegelii complex are characterised by the thickened clubs on the three sepals, petals shorter than the long sepals, fringed (either short or long) labellum with four or more rows of calli. All of these features can be seen in Pauline’s photograph but the leaf is not so easily seen which should be long, hairy and curve inward. In all there are said to be twenty two species within this complex of which twenty are named.
References:
Brown et al (2013) Field Guide to the Orchids of Western Australia, Floreat, WA Simon Nevill Publications.
Jones, David L (2006) A complete Guide to Native Orchids of Australia, Frenchs Forest, NSW: Reed New Holland
Jeans, Jeffrey & Gary Backhouse (2006) Wild Orchids of Victoria, Seaford Vic: Aquatic Photographics.
Bates, R. J. (2011) South Australia’s Native Orchids NOSSA DVD, Adelaide
This was the question posed to Les Nesbitt at the September monthly meeting. Later there was some further discussion, of which see below:
When do I stop watering my Greenhoods?
The short answer is when the leaves go yellow and start to die off, usually in October- November. Allow the pot to dry out completely to dry up the roots and old tubers so that they do not go mouldy and rot the new tubers.
Australian terrestrial orchids form tubers underground. The mature plant dies back at the end of the growing season and enters a period of dormancy which for South Australian terrestrials is over summer.
A general principle of watering is to match the watering to the rainfall pattern. Whilst there is minimal rain over summer, when dormant tubers are in pots it is important to not let them stay dry for months and become desiccated. A light sprinkling every week or two is sufficient.
Pterostylis ‘Nodding Grace’ This is an hybrid between P. nutans and P. curta. Obviously it is not time to stop watering.
When do I start watering again?
For the cauline group (Diplodiums) from South-eastern Australia start watering at the end of January as the tubers are starting to shoot by then. For other greenhoods start light watering in late February and gradually increase the water until shoots appear usually in March-April. Do not let the pots dry out once leaves are visible.
Diplodium robustum – one of the cauline greenhoods. Note difference the between the leaves of the non-flowering rosettes and the flowering plants.
Other cultivated Australian terrestrial orchids require a similar watering regime although leaves of some appear later in May or June.
100 years ago on 15 July 1915, the state government declared Morialta a National Pleasure Resort. The Friends of Black Hill and Morialta have been holding a series of public events to celebrate the Centenary of Morialta. As part of the celebrations, the Native Orchid Society of South Australia has conducted some orchid walks in the park.
In 2004, an interim Flora Species List was produced by the then Department for Environment and Heritage and 39 orchid species were listed. It is an interim list and considering that the park is 5.33 square kilometres with a range of different habitats, it is possible that there are more species than originally listed.
One native species not included on the list is Caladenia latifolia but its presence is well known to members of the Native Orchid Society. Unfortunately the South African weed orchid Disa bracteata (Monadenia bracteata) hasalso been found in the park.
In this video most of the shots have not been taken at Morialta but it does showcase some of the orchids that can be found in the park.
Of the five entries this month, three were spider orchids and the winner was from this group. It was Rob Pauley’s Arachnorchis cardiochila (syn Caladenia cardiochila), Heart Lip Spider Orchid which can be found across South Australia and into western Victoria. At one time a specimen was found on Flinders Island, Tasmania but as it was collected in 1947 it is considered extinct in that region.
This lovely flower is quite variable in colour and form.
The heart shape labellum is a distinctive feature of this spider orchid, so it is not surprising that this is reflected in the name. Cardio means heart and chila lip.
What probably is surprising is that the traditional heart shape symbol has come full circle. It had a botanical origin. According to cardiologist Professor Armin Dietz the symbol was originally a stylized vine/ivy leaf as evidenced from paintings on goblets from the 3rd millennium. In the Middle Ages, doctors and anatomists used the shape to represent the heart. As at that time Latin and Greek were both the international languages of scholars, including doctors, the word associated with the symbol was the Greek word kardia (ie cardio) meaning heart. Consequently, by the time Ralph Tate names this species in 1887, the shape has become intrinsically linked with the heart and so it must have appeared to him as an obvious descriptive name.
There are several field guides which give a detailed description of the species including South Australia’s Native Orchids DVD-ROM which is available for sale from NOSSA.
The texts published on this website are taken from his book “Ewige Herzen – Kleine Kulturgeschichte der Herzbestattungen” (“Eternal Hearts – a short cultural history of heart burials”), published 1998 in MMV Medien und Medizin Verlag, Munich. (English translation by Pauline Liesenfeld.)
Orchids can be incredibly easy to identify or frustratingly difficult. For instance, the Flying Duck orchid is easily recognizable. The name says it all. But for many other orchids, particularly the ubiquitous blue sun orchids, it is necessary to make careful observations.
In this collage there are several species, but which is which?
For sun orchids the most important distinguishing feature will often be the column, details of which are described or illustrated in orchid keys. For example Bates and Weber, Orchids of South Australia (1990) has an illustrated dichotomous keys showing the different types of columns.
Images from Bates & Weber, Orchids of South Australia, pages 147 to 150; courtesy of the Board of the Botanic Gardens and State Herbarium.
With today’s cameras, it is possible to photograph the column, preferably from front, side and above. This helps greatly with identification.
The following photographs illustrate the variety of columns.
Thelymitra megcalyptraThelymitra X truncata – a natural hybrid
And it is not only the blue orchids that can be a problem, in South Australia; there are three pink orchids which are different in size and flowering time, features that are not obvious in a photograph, so the column is a helpful identification tool.
Thelymitra luteocilium – has tufted hairy column armsThelymitra rubra – has finger-like column arms and no tuftThelymitra carnea – has smooth column arms
And just what is the column? It is the reproductive organ of the orchid flower and is unique amongst plants because it is the fusion of the male (stamens) and female (pistil) parts. It is usually found in the centre of the flower and both releases and receives the pollen sac.
NOSSA 