Australian orchids – Page 18

Australian Orchids & the Doctors they Commemorate Part 17 of 20

Hugo Flecker (1884 – 1957)

A pioneer Australian radiotherapist, radiologist, general medical practitioner and toxicologist of Cairns (Queensland) who dug his own radioactive ore at Radium Hill (South Australia), a medical graduate from the University of Sydney, and a natural historian; his life and works are commemorated by the Flecker Botanic Gardens in Cairns.

Orchids

Cestichis fleckeri (= Liparis fleckeri) Slender Sphinx Orchid

Thelychiton fleckeri (= Dendrobium fleckeri) Apricot Cane Orchid

Those Blue Orchids Again …

Volume 31, 2013 of the Muelleria contains an orchid article by Jeffery A Jeanes. The title may be long – An overview of the Thelymitra nuda (Orchidaceae) complex in Australia including the description of six new species – but the subject is of interest to all of us who want to know our sun orchids, many of which are not always easy to identify.

By way of introduction, Muelleria is the Royal Botanic Gardens of Melbourne official research journal and has been published since 1955.

Though a technical article there is much to be gleaned for the ordinary reader, for instance the article contains a good description of the commonly used terms for describing the column for example stigma, trichomes, anther, post anther lobe, etc. This is helpful to know as the column structure is often the main feature of the plant used to identify the individual species. Naturally the key features of the T. nuda complex are covered comprehensively, as well as a brief discussion of the taxonomic history.

Another helpful section is the dichotomous key for all fifteen species described in the article. Of the fifteen species four are found in South Australia and are pictured below. But to discover more read the article ……

T megcalyptra130927 — Thelymitra megcalyptra

Thelymitra glaucophylla photographed by Robert Bates

Breaking up is …. easy to do

Attempting to divide a large Dendrobium taberi (Dendrobium speciosum var. hillii or Thelychiton tarberi) for the first time can be daunting but with a little instruction and guidance it is not quite as hard as it seems. If left, these plants just get bigger and bigger ……

… and if you would like to see a magnificent one that’s in flower, click here.

Here is my first time attempt at dividing a Dendrobium tarberi.

First the pot was allowed to dry out a bit – no watering in the days before.
- A drier plant is easier to divide.
All the necessary equipment was assembled before starting
Assembled equipment including Snail repellent, Bleach for cleaning pots & equipment, wettable sulphur for putting on the fresh cuts
- All equipment to be used was disinfected.
- For though tough, the plants will be placed under stress making them vulnerable to the risk of infection.
The pots were washed in bleach as per instructions on the container, including the wearing of gloves.
The plant was removed from the pot by
- by giving the pot some good knocks with a mallet. This loosened the plant and made it easier to remove without damaging the pot
- and then it was given a good shake to remove the loose potting mix
Next the plant was examined for areas of natural cleavage which were then pulled apart.
- This is the place to start dividing the plant.
The plant was still quite big so then tried using a mallet to try and loosen the plant and find more natural cleavages but wasn’t successful
The whole plant was picked up and dropped from chest height several times
- This finally caused the plant to split
As the plant started separating two techniques were employed
These plants are tough – no need to use kid gloves
- An axe and mallet were used to lever the larger divisions
- Smaller divisions were twisted by hand
Throughout the process old roots were pulled off or cut away
- Old roots are soft, spongy and dirty looking
- New roots were white and firm to touch – see photograph above
Once the initial canes were divided they were examined for further division This decision can be a case of personal preference.
- In the picture below this section could have been split in half but it was decided to leave as one piece
Next the split canes were well dusted with wettable sulphur
- To make this easier the sulphur was put into a stocking and used like a powder puff
Before commencing the potting on, many of the dried white sheathes on the canes were removed
- This can be a source of stagnant water collection resulting in rotting or infection
Finally it came to potting on. A mixture of two types of orchid potting mix was used – Orchid Mix with fertilizer and Orchid mix with 8 – 18 mm bark
- The reason was that the mixture needs to be open to allow air movement. Normal potting mix would be too compact. Dendrobium are epiphytes not terrestrials but they can be grown in pots.
The canes were placed upright in the pot and the mix placed around.
- As these are heavy plants, stakes were used to secure the canes upright
Each plant was then labelled
- An important process so as to not get them confused with other plants – many can look similar
- The name and date were written on lollypop stick
Finally the pots were given a light fertilizer, less than a teaspoon, and watering, then sprayed with Escar-go, a copper spray a snail and slug repellent.

Other grower may do things a little different from what is describe here but this is the method that was shown to us.

Lesson – breaking up is easy to do even if it is hard work, but worthwhile hard work.

The finished product - lots of lovely new plants! — The finished product – lots of lovely new plants!

PS – It did take three of us to do the one pot and so I would like to thank Jan and Sandra for their help.

PPS – Encouraged by how easy it was to do, the following week two of us divided two other Dendrobium – D. speciosum and D. kingianum (white) but we only took pictures of the D. kingianum and to see what it will look like when it flowers, click here.

Australian Orchids & the Doctors they Commemorate Part 15 of 20

Charles Stanford Sutton (1895 – 1950)

A Melbourne general medical practitioner and expert on subalpine flora.

Orchids

Pterostylis suttonii Name not found in the Australian Plant Name Index or International Plant Index
Prasophyllum suttonii or Mauve Leek Orchid

Another Summer Orchid

Just on Christmas, NOSSA received an enquiry from Tim in the South East about an orchid he had photographed. He knew about Dipodium roseum but in 20 years he had not seen one like this one.

From the photograph that he’d sent, it was obvious that it was a Gastrodia. In South Australia there are three species ranging in size from the smaller G. vescula (Limp Potato Orchid) through to G. sesamoides (Cinnamon Bells or Common Potato Orchid) to the larger G. procera (Tall Potato Orchid). Whilst G. vescula and G. procera are limited in South Australia to the South East, G. sesamoides is also found in the Southern Lofty and Kangaroo Island regions.

Tim’s orchid was G. procera. The features that set it apart from the other two were the time of year – late December whereas both G. sesamoides and G. procera would have finished flowering (and for 2014 most orchids finished flowering earlier than usual); the spike was crowded and the plant was upright but G. sesamoides has a bent or droopy spike when in bud and G. vescula is small with very few flowers.

Though Tim considered the photographs to not be very good, he’d photographed the necessary features to help with identification. Another feature seen in his picture is the warty appearance of the plant compared with the photograph of the G. sesamoides.

Gastrodia procera or Tall Potato Orchid — Gastrodia procera (Tall Potato Orchid) Note the upright spike and the ‘wartiness’

Gastrodia sesamoides (Cinnamon Bells or Common Potato Orchid)

Although it is has no conservation rating federally and may even be considered secure in the Eastern States, in South Australia it is rated endangered, so well done to Tim for spotting it!

It was possible to identify this orchid from the information found in South Australia’s Native Orchids, an electronic book produced and sold by the Native Orchid Society of South Australia. Identification was confirmed by one of our most knowledgeable members.

‘Tis the Season … for Dipodium

For many with Christmas and New Year holidays it is a busy time but not so with the orchids here in the Adelaide region. The vast majority of orchids have finished flowering for the year except for a few including one of our most showy orchids, the Hyacinth Orchids (Dipodium species). Of the four species found in South Australia, two are found in Adelaide Hills – D. roseum or Common Hyacinth Orchid and D. pardalinum or Small-spotted Hyacinth Orchid and these will be flowering across the whole of the summer period.

Both of these Dipodium species are leafless plants that are dependent upon mycorrhizal fungi associated with stringy bark trees, either Eucalyptus obliqua or E. baxteri. This growth requirement makes it impossible to grow in cultivation. (Stringy bark trees can’t be grown in pots!) The emerging stem and buds resemble an asparagus shoot. The stems can range from a light green through to a deep dark red. At this stage it is difficult to tell the two species apart although if there are yellowing tips on white buds it may be a clue that the plant could be D. pardalinum.

Once in flower D. roseum has a surprising range of variation from carmine (a lightly purplish deep red) through to pink to white, with suffused rather than clearly defined spots. On paler or white flowers these blotches may appear pale mauve-pink rather than candy-pink. It always has a distinctive striped labellum.

This feature sets it apart from D. pardalinum which has a clearly spotted labellum and in contrast to D. roseum, the flowers lack variation of colour but are consistently white with small well-defined candy spots. (There are other Dipodium species with larger spots.)

Note the yellow staining on the bud and no stripes on the labellum

And the final word, D. roseum is common but D. pardalinum is rated vulnerable in South Australia.

Reference: South Australia’s Native Orchids Bates 2011

2014 November Photograph Competition Part 1

With a theme of Orchids and Insects for the November meeting it was hoped that there would be some entries with pollinators and therefore there would be two categories Insect Visitors and Pollinators. This month’s article will feature the Pollinator section and Insect Visitors in the next month.

In all there were four potential pollinator photographs. The insects were either scrounging around at the base of the column or else they had the pollinia attached to them. Unfortunately only one was a true pollinator so the category became Insects with Pollinia. The winning photograph of Arachnorchis brumalis with an unidentified hoverfly was taken by Chris Davey. Interestingly the other two pictures also featured Arachnorchis species with the hover fly Simosyrphus grandicornis. Resembling a wasp but minus the sting, this species is one of the common hover flies native to Australia.

Called Hover Flies owing to their ability to hover motionless in one spot, they are also known as Flower Flies because they are often found hovering around as well as pollinating flowers. It is not surprising, therefore, to find them around orchids. Yet instead of being called pollinators they are non-pollinators (Bates & Weber 1990). They visit the orchids, forage inside the flower and may even manage to collect some pollinia^₁ but that is all. They may not necessarily visit another flower of the same species but if they do, they will fail to deliver the pollinia to the stigma².

Rudie Kuiter agrees with Bates that hover flies are not orchid pollinators but just when we think we have worked it out he adds “but we have at least one orchid in Victoria that is pollinated by hoverflies and witnessed now several times and this is Caladenia catenata” (synonym Petalochilus catenatus). Notwithstanding the case for this species, it would appear that in most cases hoverflies remove pollinia so that it is not available to a more specific pollinator.

Why then are the hover flies attracted to the orchids? Is it for food? An internet image search revealed that hover flies visit the flowers of many different genera including Thelymitra and Diuris. This is interesting because flowers are the food source for hover flies but though many orchids promise food, many species do not produce the nectar and pollen (as a food source) that they desire. Diuris and Thelymitra belong to this group of non-nectar producing flower. Other orchids that don’t produce nectar include Gastrodia, Dipodium and the Duck orchids. Again, there are orchids such as Crytostylis which produce minimal nectar and with Prasophyllum the nectar is hidden in cells that require puncturing – not a good food source!

Having discussed hover flies as non-pollinators, in this month’s competition, which photograph had a pollinator? – It came last and was Robert Lawrence’s photograph of a native bee on a Dipodium pardalinum, another non-nectar producing orchid. The story of this photograph was featured in Photographing Orchid Pollinators, April 2014 Journal as well as in a previous blog on Photographing Pollinators.

References:

Smith James, Information Centre, South Australian Museum, personal communications

Kuiter Rudie personal communications

Bates and Weber, Orchids of South Australia, 1990

Australian Museum, http://australianmuseum.net.au/Hover-flies Accessed 4th December 2014

Brown, et al, Field Guide to the Orchids of Western Australia, 2013

Jones, Native Orchids of Australia Including the Island Territories, 2006

Bates, South Australia’s Native Orchids 2011 DVD-ROM

Martin, The Vocabulary of Orchids: An Amateur’s Perspective, 2005

¹Pollinia is basically a coherent compact mass of pollen that allows the pollen to be transported as a single unit

²The stigma is a sticky depression (or swelling) at the front of the column, the receiving surface for the pollinia that is necessary for germination.

Australian Orchids & the Doctors they Commemorate Part 13 of 20

Thomas Lane Bancroft (1860 – 1933) son and Joseph Bancroft (1836 -1894) father

Thomas Lane Bancroft is one of Australia’s greatest doctor-naturalists; he elucidated the life cycle of the lungfish, Neoceratodus forsteri

Orchid Species

Sarcochilus dilatatus (= Sacrcochilus bancroftii) Brown Butterfly Orchid

Australian Orchids & the Doctors they Commenorate Part 12 of 20

Herman Beckler (1828 – 1914)

A general medical practitioner in Ipswich and Warwick (Queensland) and, after 1862, in Germany; in 1860, he travelled with the Burke and Wills expedition as a doctor–botanist and expeditioner in Victoria and New South Wales.

Orchid Species:

Dockrillia schoenina (= Dendrobium beckleri) or common name Pencil Orchid

Papillilabium beckleri or common name Imp Orchid

October 2014 Winning Photograph

This month’s entries of Oligochaetochilus arenicola, Caladenia flava, Calochilus robertsonii , Diuris palustris and Caladenia procera illustrated the variety of shapes to be found in orchids.

All but one are reasonably common; all but one were photographed in situ and that one was the winning picture by Kris Kopicki – Caladenia procera. Its common name, Carbunup King Spider Orchid, reflects its location near Busselton Western Australia. This species has a severely limited distribution with a small population and is threatened by land clearing for development. Consequently it is rated as critically endangered.

The other aspect of this plant is that it is a photograph of a plant in a pot not the bush. Kris benched the original plant at the September Tuesday meeting when it was still in bud. By Saturday it was in glorious flower.

This picture exemplifies the two objects of NOSSA which “are to promote and engage in activities for the promotion and furtherance of:

the culture, propagation, conservation, knowledge and scientific study of the native orchids of Southern Australia and the Australasian region;
the preservation of orchids as a species and their preservation within their native habitat.”

Some terrestrial orchids are relatively easy to grow but not this one. It takes time patience and skill to grow them. C procera is one of the fungi dependent species and though capable of living many years, it can take up to six years before flowering, although under ideal condition it could mature in as little as two years.

Being able to grow the different terrestrial orchids is one of the ways NOSSA can help in their conservation. NOSSA has a Growers’ Forum each meeting night where members can attend and learn from experienced growers how to grow both epiphytes and, importantly, the terrestrials.

Reference:

Native Orchid Society of South Australia Inc. (NOSSA) Rules of Association 2007

Caladenia procera – Carbunup King Spider, Orchid Species Profile and Threats Database (SPRAT) – http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=68679 – access 6^th November 2014

Remember November’s theme is Orchids and Insects (Spiders and other critters accepted as Honorary Insects)

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