Australian orchids – Page 16

2015 July Winning Photograph

Anzybas unguiculatas (common name Little Pelican or Cherry Helmet Orchid) was the main focus for this month’s competition with three photographs of this diminutive flower.

The other photographs were Ed Lowrey’s close-up of a triggered Urochilus sanguineus labellum, John Badger’s first Diuris palustris sighting for this year and Pauline Meyer’s mass flowering of Leptoceras menziesii post fire. Of the Anzybas, Jenny Pauley entered two and Lorraine Badger one. Jenny Pauley’s photograph of two flowers was the outstanding winner.

Originally named Corysanthes unguiculata (1810), then Corybas unguiculatus (1871), the genus name was changed in 2002 to Anzybas in recognition of its distribution both in Australia in New Zealand. Since 1945 it had been recognised that the New Zealand species Corybas cheesemanii was a synonym for Corybas unguiculatas although the juvenile plant can have two leaves unlike the Australian species which is single leafed.

An interesting feature of this flower is the prominent white ears at the rear of the helmet (not clearly seen in this photograph) which are part of the labellum.

These plants are small. The gum leaves and twigs give an idea of size but the engagement ring shows it very clearly. Note also the prominent ‘white ears’ of the labellum.

An unusual aspect of this photograph is that the colour of the underside of one of the leaves. It lacks the characteristic distinguishing feature of the purple underside of the leaves. According to orchid growers, the light affects the leaf colour. Heavy shade produces green leaves. It is possible that the heavy leaf litter where this plant was growing provided enough deep shade to cause the colour loss.

Bates (1990) states that it (has) not proved amenable to cultivation, but it has, on rare occasions, been benched at NOSSA meetings with the most recent occurrence was in July 2010 but it remains a very difficult plant to cultivate. The electronic version Vol 34 No 7 has a photograph of the plant just visible within the moss.

It is not always easy to photograph this species as not only is it rare with limited numbers but there are very few sites where it can be found. Added to that is that the window of opportunity is short in South Australia with a flowering time from June to August compared with those interstate which can range from May to October.

There has always been an interest in Australian orchids. Over the years there have been many photographs of orchids. This stereographic postcard from 1928 is a study in beauty –

This postcard is held by the State Library of Victoria.

Although the distribution covers the Southern Lofty, Kangaroo Island and the South East regions of South Australia, it has become increasingly rare due to loss of habitat which consists of leaf litter on damp soils. As a result, there are very limited localities where they can now be found.

It is one of our earliest helmets to flower which is from June to July.

References

http://www.flora.sa.gov.au/cgi-bin/speciesfacts_display.cgi?form=speciesfacts&family=&genus=corybas&species=unguiculatus&iname=&submit=Display accessed August 5 2015

Les Nesbitt personal communication

Jones, David L (2006) Native Orchids of Australasia, Frenchs Forest, NSW: Reed New Holland.

Bates, R.J. & and Weber, J.Z. (1990). Orchids of South Australia, Adelaide: Flora and Fauna of S.A. Handbooks Committee

https://biodiversity.org.au/nsl/services/instance/apni/499184 accessed August 5 2015

https://www.anbg.gov.au/cpbr/cd-keys/orchidkey/html/genera/Anzybas.htm accessed August 5 2015

Bates R, (Editor) 2011 South Australia’s Native Orchids (CD-ROM), Adelaide: NOSSA

Journal of the Native Orchid Society of South Australia Vol 34 No 7 August 2010

http://rsnz.natlib.govt.nz/volume/rsnz_76/rsnz_76_04_007280.html accessed August 5 2015

Rupp, HMR and Hatch, ED (1945) Relation of the Orchid Flora of Australia to that of New Zealand in Proceeding of the Linnean Society of New South Wales Vol 70 1945, pages 53 – 61

https://archive.org/stream/proceedingsoflin70linn#page/60/mode/2up accessed August 5 2015

Orchid Pollination Strategy for Corunastylis littoralis (Part Two of Two Parts)

Part Two – Different Ways of Orchid Reproduction

Part One – Attracting Pollinators looked at pollination strategy, but the fourth aim of the paper was to establish that Corunastylis littoralis reproduced by xenogamy or geitonogamy and that the species was not autogamous or apomictic, that is, pollinated, self pollinating or non pollinating plants.

Xenogamy or geitonogamy that is vector mediated pollination or out-crossing is when fertilization occurs by the transfer of pollen from one flower to another flower usually by the means of insect.

Autogamy or self-pollinating is when the flower is pollinated by its own pollen.

Apoximis is when reproduction occurs without pollination, that is, vegetative reproduction.

As explained in the paper, there are visual clues for determining which process is used by the plant.

Xenogmay	Autogamy	Apoximis
Pollinia removal and pollen deposition	Pollinia not removed	Lacks pollen or it is tightly bound
	Pollinia weakly attached to the viscidium	If pollinia present, then unable to be removed
Not all the ovaries are fertilized	All the ovaries are fertilized and have viable seeds
		Swelling of the ovaries can occur whilst in bud
Perfumed	Likely to have no perfume
Attracts insects
	Flowers short lived

More detailed information was gained by dissecting the flower.

To read the full paper, click here.

To read the report, click here.

Thank you to Colin Bower for checking this post and for allowing the use of his photographs.

Orchid Identification Quiz #1

In 2006 the electronic version of the Journal of the Native Orchid Society of South Australia Volume 30 No 2 March contained a quiz – Do you Know Your Leaves? It featured photographs of the leaves of 15 different orchid. In 2011 Robert Lawrence produced a book titled Start With the Leaves which was based upon the premise that the flower is not always present but identification is still possible.

Many but not all can be identified to species level by the leaf alone.

So here is the web version of the original quiz – how well do you know your leaves?

Hint – 20 of them are South Australian, more specifically, the Mount Lofty Ranges region. One is a weed.

Did you get them? Click on the image to go to the name and pictures of the flower. As a couple of the links are not working and until I have time to rectify them, click here to find the all answers in the Journal.
It will be on the last page.

More to come another time ………

Growing Dendrobium falcorostrum 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. 5, June, 1983

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

Dendrobium falcorostrum (Beech Orchid)

This is one of the most attractive of the New South Wales epiphytic orchids, the common name being derived from the fact that it is only found in the forests of the Antarctic Beech, which occur in the highlands, extending from the Barrington Tops in New South Wales northwards to the McPherson Ranges in southern Queensland. However, within those forests it does occasionally grow on other than beech trees.

Due to the clearing of those forests it is fast becoming an “endangered species”.

It is a plant of the highlands and is rarely found below 900 metres, consequently it will tolerate cold conditions, however, it requires protection from frosts and needs to be grown where there is plenty of air movement.

There are from two to six light green lanceolate leaves at the top of the stem which is from 12 to 50 cm high and the mature stems are ribbed. The flowers number from four to 20 in the raceme and are intensely fragrant during the warmer part of the day. They are from 3 to 5 cm in diameter.

Flower spikes are terminal and some stems will flower for two or three years.

They are a glistening pure white to cream with the exception of the labellum which is streaked with purple. The common name is derived from the labellum, which is short and broad, bearing a fanciful resemblance to a falcon’s beak. The flowering season is from August to October.

It can be grown using either slab or pot culture using a mixture of aged pine bark, scoria* and charcoal* in a plastic pot and grown under 50% shadecloth.

Fertilise lightly during the growing season using foliar fertilisers at half the recommended strength.

Propagation is usually by division.

*NB Charcoal is no longer used and scoria can get cold and wet in winter.

Orchid Pollination Strategy for Corunastylis littoralis (Part One of Two Parts)

Part One – Attracting Pollinators

In 2015 a paper was published in the Journal of Plant Systematics Telopea (Vol 18:43-55) titled “Reproductive success and pollination of the Tuncurry MidgeOrchid (Genoplesium littorale)(Orchidaceae) by Chloropid Flies “. Much of the same material had been published earlier in a consultancy report for UrbanGrowth NSW, under the title “Pollination of The Tuncurry Midge Orchid (Corunastylis littoralis) Amended June 2014″ Prepared by Colin C Bower PhD.

Because of their details, research papers can contain some very interesting facts of interest to a wide range of readers. This paper was no different. The aim of the paper was to identify the pollinator(s), how the attractant worked, confirm that C. littoralis was not autogamous (self-fertilizing) or apomictic (reproduction without pollination) and to assess the requirements & long-term viability of the pollinator.

The following summary notes have been drawn from both the research paper and the consultancy report. Note that Corunastylis littoralis is a synonym of Genoplesium littorale.

One of the interesting issues discussed was the different types of pollination strategies employed by orchids. It is commonly accepted that about one third of orchids use deceptive practices to attract a pollinator whereby they promise but don’t deliver. Some of these strategies are quite unusual. It would appear that there are at least four strategies now known. In order of frequency they are

Food mimicry
Sexual mimicry
Brood-site mimicry
Prey/carrion mimicry

The first two are well known to many orchid lovers. The orchid promises food such as nectar but does not produce any nectar or it has the appearance and even odour of the female insect pollinator so that it fools the male. The lesser known deception is brood-site mimicry where the female insect pollinator is tricked into laying the eggs on the flower but there is no chance for survival of the off-spring. Finally the most uncommon and unusual deception of prey or carrion mimicry, known as kleptomyiophily.

This method was discussed in detail in the report and made for fascinating reading although it was helpful to have a dictionary on hand.

Some insects are kleptoparasitic that is they feed on the haemolymph (roughly similar to blood) but from freshly killed insects. The researchers established that the pollinator for C. littoralis was not Drosophilidae (vinegar fly) but were instead from the families Chloropidae and Milichiidae known kleptoparasitic flies.

It has been observed that the pollinators swarm around the Corunastylis. This is a known behavioural pattern of kleptoparasitic flies that are attracted to the prey of other predators such as spiders, robber flies and other predatory insects.

It was noted that the pollinators were dominated by females. This precludes sexual deception and suggests that the females may require the haemolymph, which is protein rich, for egg maturation. It was also noted that C littoralis is a nectar producing orchid. It was considered that the nectar contained properties that mimic haemolymph.

Based upon these observations it was hypothesized that prey mimicry pollination syndrome was the best fit for the Corunastylis. Though this syndrome has been observed in orchids in the northern hemisphere, this would be the first time that this has been demonstrated as a possibility for Australian orchids.

Part two will consider the fourth aim of the paper which was to determine the method of reproduction.

Thank you to Colin Bower for checking this post and for allowing the use of his photographs.

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

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)

References

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Part Two – Different Ways of Orchid Reproduction

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Part One – Attracting Pollinators

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