Australian orchids – Page 16

2015 June Winning Photograph

Of the five entries this month, four featured winter orchids. Lorraine Badger entered a Diplodium robustum, whilst Claire Chesson, Robert and Rosalie Lawrence all entered Urochilus sangineus. Though not the winning photographs it was interesting to see the differences between the U. sangineus with one being no taller than the small Acianthus pusillus next to it and another being taller than the rapier sedge.

But the winning photograph was the spring flowering Arachnorchis argocalla (White Beauty Spider Orchid) by Pauline Meyers. This is amongst our most threatened orchids and is dealt with in depth in the Recovery Plan For Twelve Threatened Orchids in the Lofty Block Region of South Australia 2010. This fungi dependent endemic orchid is rated Endangered both at State and National level.

Found in the Southern and Northern Lofty regions, it range has been severely reduced by possibly 80%. Since 1918 no plant has been found south of Adelaide.

Flowering from September to October, it is often found in grassy woodlands often growing on gentle southerly-facing hill slopes. The soil is a clay loam with a high humus content.

This beautiful orchid has one to two non-perfumed white flowers with thickened but not clubbed drooping lateral sepals and petals. The strongly recurved broad labellum is usually white, sometimes crimson, fringed with short teeth.

This is one of our larger spider orchids reaching a height of 60cms. The size of the plant flower and leaf help to distinguish it from other similar appearing orchids such as A. brumalis and albino flowers of A. behrii.

Like many of the spider orchids it takes 2 – 5 years to reach maturity and then has a potential reproductive life of 10 years. With an average pollination rate of less than 10%, the potential to increase the population is low and any threat to survival of the individual plants needs to taken seriously.

Some threats are obvious such as weed invasion including the garden escapees such as Topped lavender (Lavandula stoechas spp. stoechas) and action is being taken to curb the spread of weeds through targeted weeding programs.

Another threat is habitat loss. This has been the result of land clearing but sites are being protected either through conservation legislation or Heritage Agreements. Habitat loss can also occur indirectly and that is through Phytophthora being introduced into the sites. Although the direct effect of Phytophtora on the orchid is unknown, it is known that it can affect the plants that grow in association with this orchid. This threat can be reduced by all of us implementing good hygiene practices.

These were some of the threats noted in the Recovery Plan. This plan was not just defensive, ie attempt to halt and minimalize the damage; but it was also proactive with measures outlined to increase the population. These included seed and fungi collection eventually resulting in germination and cultivation with a view to re-introduction.

It is good to see that there is a plan and active steps are being taken to bring this orchid back from threat of extinction.

June 2015 other entrants — Photographers from L to R: Claire Chesson, Rosalie Lawrence, Lorraine Badger, Robert Lawrence

References

Websites accessed 1 July 2015

White Beauty Spider Orchid (Caladenia argocalla) Recovery Plan
http://www.environment.gov.au/archive/biodiversity/threatened/publications/recovery/c-argocalla/index.html
Caladenia argocalla – White-beauty spider-orchid, biodiversity species Profile and Threats Database
http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=54991
Recovery Plan For twelve threatened Orchids in the Lofty Block Region of South Australia
http://www.environment.gov.au/system/files/resources/e362cfd2-a37b-443a-b007-db3a2b7b64dd/files/lofty-block-orchids-recovery-plan.pdf

Bates R J, South Australia’s Native Orchids 2011 DVD

Growing Dendrobium linguiforme in Adelaide 1983 and Now

In 1983, Ron Robjohns, NOSSA’s first treasurer, wrote a comprehensive series of articles about growing epiphytes in South Australia. Thirty years on Ron’s information for growing is still helpful and applicable for today. Any updates or extra information are in black text.

NATIVE ORCHID SOCIETY OF SOUTH AUSTRALIA JOURNAL

Volume 7, No. 4, May, 1983

GROWING EPIPHYTES IN SOUTH AUSTRALIA – R.T. Robjohns

Dendrobium linguiforme (Tongue Orchid)

The plant is epiphytic or lithophytic, forming large masses on trees or rocks. Its range is from the extreme south-east of New South Wales to at least the Burdekin River in Queensland. It grows from sea-level to altitudes of around 1000 metres, but is confined mainly to the coastal areas, although it has been found up to 250 kilometres inland. The inland plants have smaller, tougher leaves than those of the coastal areas, due no doubt to the harsher conditions under which they exist. It is not confined to a specific host but is found on quite a large variety of trees.

The rhizomes are prostrate and branching with thick, tough ovate leaves, 3 to 4 cm long having distinctive longitudinal furrows on top.

The racemes, up to 15 cm long, grow from just below the base of the leaf and bears from six to 20 flowers. The flowers are usually white or cream with a number of faint purple markings on the labellum.

The flowering time is usually August-September here but earlier in the tropical areas.

It does not lend itself to pot culture but is very hardy and with a little care will grow freely on cork or hardwood slabs. I have had good success using pieces of Melaleuca on which it readily establishes itself. It receives approximately 75% shade. It should be protected from our frosts and can be fertilised using foliar fertilisers at half the recommended strength.

This is the variety of the species on which the genus Dendrobium was founded. It was first described by O. Swartz.

There are three varieties of this species, the best known of which is var. nugentii, which is a tropical form from about the Burdekin River north to Bloomfield River in the south-east of Cape York Peninsula.

This form has broader, thicker leaves which are more rounded at the apex and in addition to the longitudinal furrows it often has transverse furrows. The flowers of this form are slightly smaller and age quicker.

Moving Labellums

The following article titled Moving Lablellums written by Helen Lawrence is reproduced from the NOSSA Journal Volume 36 (1) February 2012

Labellums are fascinating. Well I think they are fascinating, especially the ones that move.

Bunochilus viriosus labellum down — Bunochilus viriosus with the labellum down

Why do these labellum move? You may have observed that the orchids which have labellums often have “hoods” and inside these “hoods” are the pollen. It is quite simple, the pollinator lands on the labellum, triggers it and is held captive by the labellum. As it struggles to free itself it pollinates the orchid. Clever, isn’t it?

Bunochilus viriosus labellum up — Bunochilus viriosus with the labellum up

So that these labellums can capture the insect they need to be sensitive. Consequently they can easily be “set off.” This can happen with of a gust of wind, or if the plant is in a pot, the labellum may trigger if the plant is moved/knocked.

It is easy to see these labellums as they move up into their “triggered position.” They move reasonably quickly, so the insect does not have time to respond.

However, how does the labellum return to its “normal” position? Does it slowly return to the position, or does it happen in a sudden movement in the same manner as when it is triggered?

One day when I was travelling in the car with a Pterostylis curta (Blunt Greenhood), I observed something very interesting. When I looked at the flower, the labellum was up, but then when I looked at it a minute or two later, the labellum was down. The labellum had to move quickly. However was it the bumps in the road which caused it to move? I had to find out.

I devised an experiment to satisfy my curiosity, and find out what these fascinating labellums actually do.

First I had to find an orchid with a labellum that could be triggered. I ended up using an Oligochaetochhilus bisetus (Two-bristle Greenhood).

Second I had found a good camera that could take high definition video. I placed it on a “tripod” (a pile of books).

So I had set up my apparatus, set the camera rolling, triggered the labellum, and left the room.

So what happened?

For the first six minutes after I had triggered the flowers nothing happened. There was no movement that I could see.

In the next five minutes, the labellums of the two flowers slowly moved downwards until they were half way down.

After twelve minutes of the flower being triggered, the labellum returned rapidly to its original position. This final stage of the labellum moving lasted for less than five seconds, and appeared to move at the same speed as when it was triggered.

So it looks like the labellum returns to it normal position first moving slowly and then in a rapid final movement which returns the labellum to its original position.

If I thought it would be that simple, I was mistaken.

As I briefly looked through the fifty minute video I took, I came upon something that made no sense to me.

A minute after the labellum had returned to its resting position, one of the labellums suddenly returned to its “triggered” position. What’s more, there was nothing in the room to trigger the labellum: no wind, no insects, and no people. So what triggered the flower?

I do not know. Six minutes after the labellum was triggered it returned to its original position, and then two minutes later the other flower’s labellum moved into the triggered position. The first flower was triggered again for no apparent reason at all, four minutes after the second flower was triggered and still remained up.

Once the labellums returned to their original position, there was no more movement.

Maybe triggering the labellum causes a chain reaction. Maybe the labellums periodically “trigger themselves.” Well, I can’t give you any answers, all I can tell you is that it looks like this is an example of how we barely know anything about these wild gems. They are beautiful but bizarre and of course fascinating!

After 7 minutes, just before the labellum moved

After 12 minutes, labellum about to fall

After 13 minutes, labellum in original position

As a 50 minute video is a bit long to watch, Helen has produced a four minute video, so watch and enjoy the music!

Why use a mulch on your potted terrestrial orchids?

Here in South Australia, it is very common to see a covering of She Oak needles (Allocasuarina sp.) on pots of terrestrial orchids. According to Les Nesbitt, NOSSA founding member and experienced terrestrial orchid grower, there are four reasons for this

It keeps the leaves up off the soil.
- Provides good air circulation
- Helps prevent leaf rot.
It provides nutrients to the fungi
- This is very important for the fungi dependent orchids.
It stops pitting into the soil when it rains.
- This is most likely to occur when pots are under the drip line of a shade-cloth.
- Pitting exposes the root system.
It allows the leaves to readily come through because of its small diameters.
- Other mulches, such as gum leaves, smother seedlings.

She Oak needles are the choice of mulch because it is

Long lasting and takes more than year to break down
- which means that it lasts the whole growing season.
Does not become mushy or spongy
- unlike pine needles and grass cuttings which breakdown more quickly into a wet soggy mass and contribute to leaf rot.

It should be noted that it is necessary to replace this mulch yearly.

These two pots were in the same area under the shadecloth. Notice the damage to the pot without the mulch. — These two pots were in the same area under the shadecloth. Notice the rain damage to the pot without the mulch.

2015 May Winning Photograph

Western Australia produces a lovely array of orchids and so it is not surprising to find in NOSSA photograph competitions that when a Western Australian species is entered it can often be the winner. This month was no different with Pauline Myers beautiful picture of a mass of Diuris hazeliae which was kindly identified by Andrew Brown.

This species has only recently been named in 2013 and as a result finding information was a challenge. Obviously there was no information in Jones Native Orchids of Australia (2006); and surprisingly the definitive Field guide to the Orchids of Western Australia (2013) A Brown et al did not appear to have any information.

But

the Western Australian Herbarium’s FloraBase (Western Australian Flora), has a map of distribution which is roughly a diagonal line from east of Geraldton to the north of Esperance. It is not listed as threatened.
Distribution of Diuris hazeliae. Map taken from the Western Australian Flora Base
the Western Australian Herbarium lists the species as one of 59 new taxa added to their plant census in 2014.
from the Atlas of Living Australia it can be deduced that the flowering time is mainly August and September and is likely to be found in various types of shrublands margins including Eucalypt and mallee woodlands and appears to be mainly associated with rocky or granite outcrops.
and the National Species List APNI/APC yields the information that it was named after Hazel King, plant collector and conservationist with a special interest in orchids and was previously known by the phrase name Diuris ‘northern granite’ with a common name of Rosy-cheeked Donkey Orchid. It was found in a granite outcrop on her property Tampu (north of Beacon).

Fortunately Andrew Brown was able to help with extra information. It is listed in his book (page 212) but under the phrase name Diuris sp. Eastern Wheatbelt (Yellow Granite Donkey Orchid). Diuris sp. Northern Granite was found to be the same species and so the use of that name was discontinued but it does remain a synonym for Diuris hazeliae.

The following description is information updated from his book “Field Guide to the Orchids of Western Australia”

Diuris hazeliae D.L. Jones & C.J. French (yellow granite donkey orchid)

Flowering: August to September.

Description:

A common, inland donkey orchid 100 to 300 mm high with two to three basal leaves 50 to 150 mm long by 5 to 10 mm wide and up to seven predominantly yellow, brown marked flowers 20 to 40 mm across. Flowers are characterised by their broad petals, very broad dorsal sepal, narrow, reflexed, usually crossed lateral sepals and tri-lobed labellum with broad, spreading lateral lobes and a broad, flattened to convex mid lobe.

Distribution and habitat:

Found between Mullewa, Salmon Gums and Balladonia, growing in shallow soil pockets on granite outcrops and along drainage lines below rocky breakaways.

Notes:

Named in 2013 from specimens collected at Tampu, north of Beacon in September 1997. The species often forms very large colonies on granite outcrops.

Distinctive features:

Inland granite and breakaway habitat.

Very broad dorsal sepal.

Diuris hazeliae is part of the Diuris corymbosa complex of which, in 2013, there were only 10 of the 26 Western Australian species formally named. This situation has now changed with 14 now formally named. As a final word, Diuris orientis is South Australia’s only member of this complex.

More images of this species can be seen on Retired Aussies website http://www.retiredaussies.com/ColinsHome%20Page/OrchidsWA/Diuris/Diuris%20sp%20northen%20granite/Diuris%20sp%20northern%20granite.htm

References – All websites accessed on 29th May 2015-06-04

https://florabase.dpaw.wa.gov.au/science/nuytsia/755.pdf

https://florabase.dpaw.wa.gov.au/browse/profile/44161

https://biodiversity.org.au/nsl/services/api/instance/apni/772000

Jones, Native Orchids of Australia and its Territories (2006)

Brown, Field Guide to the Orchids of Western Australia (2013)

An Examination of Two Rufoushoods

This week’s post is taking a brief look at a paper by Noushka Reiter, Mark Clements and Kate Vlcek which appeared in Muelleria, Volume 31: 69 – 76, 2013.

Titled “An examination of Pterostylis xerophila (Orchidaceae) and the confirmation of P. lingua as a new species in Victoria” this paper seeks to ascertain whether the records collected are correctly identified, that there are differences between them both in morphology and associated vegetation.

Both P. xerophila and P. lingua are found in South Australia where they are known, respectively, by the synonyms Oligochaetochilus xerophilus and O. linguus. In fact the type specimen for O. xerophilus is from South Australia.

In the introduction, the authors give a detailed description of Oligochaetochilus otherwise known as the ‘rufa group’ which differs from Pterostylis, in the strict sense, in several features. Some of the main features of this group are:

Basal rosette of overlapping stemless leaves
Leaves senesced, withered and died, by flowering
Erect multi-flowered
Flowers
- Lateral sepals
  - hang down
  - basal half joined
  - tips become long and threadlike
- Labellum
  - is very mobile
  - has obvious long white hairs and often short hairs as well

Typical of the rufus hood this Oligochaetochilus arenicola shows the sencesing leaves, pendent petals and hairs on the labellum. Photographer: H Lawrence — Typical of the rufus hood, this Oligochaetochilus arenicola shows the sencesing leaves, pendent petals and hairs on the labellum.
Photographer: H Lawrence

Later in the articles, the differences between the two species are discussed. There is much of interest concerning the two species but one outcome of the research was to establish that P. lingua (O. linguus) had been incorrectly identified in the records and by correcting the names of the specimens the authors were able to confirm that it did occur in Victoria.

To find the answer to the authors other questions, read the paper

And for those that need a glossary of the terminology used, click here

For images of P. xerophila (O. xerophilus) click here

For images of P. lingua (O. linguus) click here

Growing Dendrobium kingianum in Adelaide 1983 and Now

NATIVE ORCHID SOCIETY OF SOUTH AUSTRALIA JOURNAL Volume 7, No. 3, April, 1983

GROWING EPIPHYTIC ORCHIDS IN SOUTH AUSTRALIA – R.T. Robjohns

Dendrobium kingianum (Pink Rock Lily)

This is possibly the best known and most variable of our native epiphytic orchids. Its range is along the coastal strip from the Hunter River in New South Wales to Rockhampton in Queensland. While it is principally a lithophyte and found growing in large mats on exposed rock faces, it is also found in shady gullies and on trees.

It has three to six lanceolate leaves up to 13 cm long on stems varying from slender stems, pseudo bulbous only at the base, to short stout pseudo-bulbous stems. The pseudobulbs are usually 8 to 10 cm long with some up to 30 cm in length; the colour varying from pale green to dark reddish green. One to three racemes of up to twelve flowers, often fragrant, are borne from the top of the pseudobulbs, the colour, while commonly pink, varies from white to purple. They are up to 25 mm in diameter having the labellum usually spotted and blotched with mauve. The flowering season is August to November.

It can be grown on slabs or trees (e.g. Jacaranda or Melaleuca) but locally, best results are obtained from pot culture – rafts or hanging baskets, using an open mix. Some growers use a commercial cymbidium mixture.

I have had good results by lining wire baskets with a thick layer of live spagnum moss and filling them with small pieces of seasoned pine bark and charcoal. I find that the plant not only grows up but also out of the sides of the basket.

Some shade is required in our summer I have had success using 50% shadecloth. Protection from our winter frosts is also necessary. Fertilise lightly in the growing season using commercial fertilisers at half strength.

Being hardy it is well suited to cultivation and hybridisation. D. x delicatum is a natural hybrid of D. speciosum and D. kingianum, also D. x suffusum is a natural hybrid of D. gracilicaule and D. kingianum.

A number of man-made hybrids are available. Some of the best known are D. Bardo Rose (D. kingianum x D. falcorostrum). D. Ella Victoria Leaney (D. kingianum x D. tetragonum), all of which respond well to pot culture and flower freely.*

Propagation is either by division or cultivation of “keikies”.

*The number of hybrids has increased since 1983.

Australia’s Most Popular Orchid?

Australia has some of the most varied, if not the most varied, terrestrial orchids. This variety is reflected in the words used in their commons names – spiders, hoods, moose, cowslip, mosquito, comb, fingers, fairies, bearded, ant, bird, frog, helmet, midge, shell, donkey, bulldogs, parsons, bunnies, daddy long-legs, hare, rabbit, onion, leek, gremlin, duck. This list is from words used for describing just the South Australian orchids. The other states particularly Western Australia have even more common descriptive names!

With such a variety is there a favourite one? From the searches and questions that come to this site, it would have to be the Flying Duck Orchid. This orchid never fails to amaze people with its resemblance to a duck in full flight.

It was no surprise than to discover that the winner for the Australian Orchid Foundation 2014 Essay titled Our Favourite Orchid featured the Flying Duck Orchid.

The essay began “It all started with the arrival of an email ……. click here to continue reading

And just a reminder, it is only ever found in the wild. No-one has ever been able to grow one and it cannot be bought or sold! But so that we can all enjoy them, here is a short video clip …..

11sm C major actual size — To get an idea of the size of this superb orchid, bring this image up to A4 paper size

2015 April Winning Photograph: Calochilus cupreus

Despite having five very different but high quality photographs, Helen Lawrence’s photograph of Calochilus cupreus (Aldinga Bearded Orchid) was the clear winner with the vast majority of votes.

In South Australia it is considered endemic and endangered. Researching it was interesting. For instance, there is no mention of it in Jones extensive book (2006) yet it was named by R S Rogers in 1918 with a description appearing in Black’s Flora of South Australia (1922 edition), including a drawing by Rosa Fiveash. Between then and now there was a shift. In the Third edition of Black’s (1978) C. cupreus is absent but C. campestris present. In Bates and Weber 1990 the authors describe C. campetris (C. cupreus). Currently, the eflora of South Australia (the electronic version of 1986 Flora of South Australia) considers it a synonym of C. campestris. This is reflected in the Census.

It would appear that as C. campestris was studied and its variations documented (e.g. article by Jones 1976 Orchadian 5:83) the distinction with C. cupreus was lost. Clements and Jones (2006) state “Calochilus cupreus R.S.Rogers = Calochilus campestris” which means that they are not using C. cupreus. But in Jones’ book an anomaly occurs – he does not include South Australia in the distribution of C. campestris and as result Bates, from 2008, states that it is not recognized as occurring in South Australia.

Though C. cupreus disappeared from the literature the name still continued to be discussed amongst orchid enthusiasts. So when in 1995 NOSSA members found a distinctively different colony at Aldinga they identified it as Rogers’ C. cupreus.

Below is a chart, based upon Dr Rogers’ description, of some of the differences that made him consider C. cupreus a separate species:

*C. cupreus*	*C. campestris*	*C. robertsonii*
Shorter leaf Rather rigid or fleshy erect triangular section	Longer leaf Crescentic section	Longer leaf Crescentic section
Base of labellum oblong glabrous (without hairs) with several raised longitudinal line	Base of labellum round thickened, smooth no raised longitudinal lines	Whole of labellum hirsute (hairy)
8 – 15 flowers	About 8 flowers maximum	About 8 flowers maximum

It will be interesting to watch what happens.

References

Bates personal communications

Bates & Weber (1990) Orchids of South Australia

Bates (2011) NOSSA South Australia’s Native Orchids

Bates (2005 to present) Orchids of South Australia CDs various editions

Clements and Jones An Australian Orchid Name Index (27/4/2006)

https://www.anbg.gov.au/cpbr/cd-keys/orchidkey/html/AustralianOrchidNameIndex.pdf

Jones (2006) A Complete Guide to Native Orchids of Australia

NOSSA Journal Vol 25 No 10 November 2001

Rogers R S Transactions of the Royal Society of South Australia V42 (1918) Pages 24, 25

http://www.biodiversitylibrary.org/item/113409#page/40/mode/1up

Growing Epiphytic Orchids in Adelaide 1983 and Now

NATIVE ORCHID SOCIETY OF SOUTH AUSTRALIA JOURNAL

Volume 7, No. 3, April, 1983

GROWING EPIPHYTIC ORCHIDS IN SOUTH AUSTRALIA – R.T. Robjohns

Epiphytes usually grow where there is plenty of air movement, ample light but also shade and to achieve this they are frequently found well above the ground storey in the forest from where, should they be dislodged from their host and fall to the forest floor they wither and die. With most plants the roots grow downwards, however, with epiphytes in their natural habitat, the roots may grow up, down or around their host, that is, in any direction in search of suitable conditions.

As a novice grower I urge you to learn all you can about the natural habitat of the plant and its principal host, bearing in mind that in accounts of plants that grow on rock faces, often they are growing with their roots in crevices into which any moisture drains and maybe in an accumulation of leaf litter. Frequently the rocks on which the lithophytic orchids grow are sandstone – a rock which can absorb moisture and consequently keeps cool longer than most other rocks. “In an exposed situation” should not be construed as being in full sun all of the time: usually they receive some shade.

With the possible exception of Cymbidium canaliculatum few epiphytes grow at their best in full sun in nature. Full sun in the hot dry South Australian summer will usually burn off the plants or at the best cause severe yellowing and loss of leaves. It is to be noted that this State has no native epiphytic orchids.

Most Australian epiphytic orchids grow in the coastal belt of northern New South Wales and Queensland where the average rainfall in their DRY season is much the same as the Adelaide winter or WET season with which it coincides, consequently advice that plants require to dry out during the winter should not be taken to the extreme and the plants left without water.

The three principal requirements of epiphytes are a free air circulation, a semi-shaded position and free drainage.

In South Australia epiphytes are grown in two ways, the most popular being pot culture and the other slab culture.

For pot culture the medium must be a free draining one and a mixture of “aged” pinebark, scoria and charcoal is quite effective.

Note 2015 – Today the potting media used is composted pine bark. Charcoal is not used and scoria can get cold and wet in winter.

In choosing material for slab culture consider the conditions under which you intend to grow the plants. For humid conditions cork is ideal while tree fern, which holds moisture longer, is good for dry conditions, although any of our native trees with papery or corky bark is suitable. Perhaps you would wish to attach the plants directly to trees in your garden, for this purpose try Jacaranda, Melaleuca or trees with a similar bark.

Watering is important, slab culture requires more watering than pot culture and in summer water orchids on slabs at least every second day and every-day during a hot spell. Water according to the weather and watch for signs of stress – in wintertime the rain is usually sufficient.

Fertilising is best done using half of the recommended strength of commercial proprietary fertilisers.

As a last general recommendation – beware of frosts. Last year (1982) the frosts in some areas of Adelaide caused severe losses amongst plants of epiphytic native orchids. Large tubs of D*. speciosum, whose thick leathery leaves I mistakenly thought frost resistant, were reduced to a mass of leafless canes; even baskets of D. kingianum hanging three feet below the 50% shadecloth had all of the leaves burnt off. These were but two of the varieties which suffered, so be warned and ensure that your plants are protected from frosts.

*D. = Dendrobium

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