Colin Ledward (1903 – 1963)
A general medical practitioner of Cloncurry and Canungra (Queensland); the orchid that bears his name was collected from a single colony discovered in 1934 and is now almost certainly extinct.
Orchid
Orchid Blogs
2015 February Winning Photograph
The number of photographs may have been few but the quality was present. The clear winner was Claire Chesson’s Thelymitra glaucophylla (Glaucous Leaf Sun Orchid). Flowering from October to December, this endemic grassy woodland species of the ranges was only published in 2013 by Jeff Jeanes in the Mulleria 31:3 – 30 (2013) but it had been recognized much earlier by Bob Bates and has appeared with this name in his electronic Orchids of South Australia since 2005. It belongs to the T. nuda complex, of which there are 15 species, six of them having only been published in 2013. This complex is characterised by having large scented blue multiple flowers that open freely.
Not seen in this picture is the leaf and though the leaf is highly variable – 10-50cm long, 8-20mm wide, erect and short, long and flaccid, Jeanes mentions that T. glaucophylla “can be identified with a high degree of confidence from the mature leaves alone” (Page 4 Vol 31, 2013 Mulleria). The main features of the leaf are grey-green glaucous ie white bloom and is often senescent (withered) at anthesis (full flowered). Of the T. nuda complex, T. megcalyptra is the most similar but its leaf is never glaucous and has a red base, as well as an earlier flowering time and habitat of plains and rock outcrops.
For more details on the other orchids in the T. nuda group see the post titled Those Blue Orchids Again … posted 30th January 2015 with the link to Jeanes article in the Muelleria
Advice from the past – Start Watering
In 1984, G.J.Nieuwenhoven was the editor of the NOSSA Journal. In February of that year he wrote the following:
Welcome back to NOSSA.
After the holiday break we are all looking forward to the next meeting to talk about our favourite plants and renew friendships.
Several members have reported an early start to the terrestrial season with Pterostylis species, a couple of Diuris species popping up already. For some of the eastern states Pterostylis of the cauline group this is normal, especially if you keep the pots cool during the summer (a cellar is ideal but underneath a shaded bench in the shadehouse will do nicely). Very light watering should take place when the first shoots appear but do not overdo the watering or place pots in the sun for we are sure to get some more hot weather yet and this could cook your plants before you know it.
The Diuris are really out of season but it was probably the rain in late December and early January that started them off, anyway, these too should be kept slightly damp if they are up.
If you have not finished repotting by now it would be best to leave it until next year as the new shoots which are already beginning to grow from the tubers are very easily broken off while sifting them from the soil.
Apart from that all you can do is wait for the rains to come in March and then start searching for plants to appear – and keep those fingers out of the pots or you may damage one of your best plants looking for the new growths.
This is also the time to start taking notes when plants first appear, etc.:
- when they flower and how many flowers from a given number of tubers;
- what kind of soil; what conditions (i.e. shaded or not, damp or dry).
- Anything that may assist in years to come to help you understand and grow our orchids better and, more importantly, multiply them.
- A card index system would be a good way to store information, otherwise an exercise book will do.
Editor
The timing of the article tallies with the advice that was recently given at the end of February – start watering the terrestrials now if you haven’t already begun. Hopefully by the flowering time you will have a lovely display of terrestrials such as the Thelymitra, Arachnorchis and Caladenia featured below.
Australian Orchids & the Doctors they Commemorate Part 19 of 20
Arthur George Harrold (1918 – 2012)
A navy surgeon who later worked as general medical practitioner, ecologist and conservationist in Noosa (Queensland), and graduate of the University of Cambridge; he formed the Noosa Parks Association in 1962 and helped establish the Cooloola National Park.
Orchid
Habenaria harroldii
Named in recent years, so there is only general information on the genus, Habenaria
Three Key Starting Points for Successfully Growing Australian Orchids
There is a lot of information on growing orchids so much so that it can become overwhelming. As a novice, I’ve put together my observations which can be summed up in three key points.
One – Find a Mentor
The best and first thing to do is to join a local orchid club, such as the Native Orchid Society of South Australia (NOSSA), and find a mentor within the group. There are many books but nothing substitutes for that personal interaction with an experienced grower who will know both the plant and the adaptions needed for the local conditions. At the monthly meetings, NOSSA has a Grower’s forum where various aspects of growing orchids are discussed and questions answered. It is well worth attending.
Two – Have an Equipment Kit
There are some things that are essential and it is good to have a basic kit to get started. Later, more equipment can be added as one’s skill develops in growing orchids. The necessary items would include:
- Secateurs
- Labels – these can be proper plant labels from a garden store or wooden lollipop sticks, so long as they are waterproof.
- Pen – indelible ink pen or pencil (there are pencils that can write on plastic) as it is pointless having a labelled plant with the details washed off.
- it may be necessary to use both current name and synonyms on the label eg Corybas/Corysanthes
- Wettable Sulphur – necessary for guarding against diseases and is available from garden centres but Tomato Dust can be a good substitute although it is half the strength.
- Sterilizing equipment
- Good nursery hygiene techniques are important
- Dilute bleach, tri-sodium phosphate (and possibly a small blow torch for metal tools)
- newspaper
- a different sheet for each orchid when dividing will help prevent transference of any disease, etc (don’t forget handwashing)
- For Epiphytes
- Ties and Stakes
- For Terrestrials
- Sieve for recovering tubers
- Sheoak or pine needles for putting on top of the pots to stop soil and fungi splashing up on the undersize of the leaves
- Pots – do not need to be fancy but the pot size will depend upon the species
- Diuris prefer deeper pots; Corysanthes prefer wider, shallower pots whilst Pterostylis doesn’t seem to mind either
Three – Work within the Plant’s Growing Condition
This will require time, research, experiment and going back to the experienced growers. Each one of us eventually needs to find what is the best setup for our individual location but some general guidelines would be:
- Start with plants that are suitable for your current climatic conditions. Obviously putting a tropical Dendrobium bigibbum under the patio in temperate Adelaide is not going to be successful. For the terrestrials it is better to start with Pterostylis curta or a Microtis than a fungi dependent Arachnorchis tentaculata.
- Research the plant you want to grow and then create the micro-climate necessary for the flourishing of the plant. This will entail separating the orchids, don’t put shade lovers such as Corysanthes with those requiring brighter light eg the Thelymitra genus.
2014 November Photograph Competition Part 2
Part Two of the November competition consisted of photographs of insects on orchids. There was quite a range of insects but the winner was a draw between Cyrtostylis robusta (Winter Gnat Orchid) with an ant and Pterostylis curta (Blunt Greenhood) with a midge fly; both taken by Doug Castle.
With today’s technology it is not only easier to take crisp images but fine details can be seen particularly when enlarging the image. Hence when the pictures are enlarged it is possible to see hairs on the ant and feathered antennae on the midge fly.
With identifying orchids, it is often the detail that is important. Both of these orchids are distinctive and can be readily identified but it is good to examine why this is the case.
With the greenhood, there is enough detail to see that the dorsal sepal and lateral petals have united to form a galea, ie hood, and that the lateral sepals are semi-fused and erect resulting in lateral orifices (side gap) between the two structures. These are some of the features that separate Pterostylis* from the other greenhoods such as Diplodium, Speculantha and Taurantha. This becomes apparent when browsing through the greenhood photographs, pages 286 to 339, in Jones “A Complete Guide to Native Orchids of Australia”. Having established that the plant is a Pterostylis, the twisted labellum is diagnostic of a P. curta as it is the only one that is described with a twisted labellum. Although not all the identifying features are present, enough information is available in this picture for identification.
In contrast the photograph of the Cyrtostylis robusta only has sufficient data to confidently identify it as a Cyrtostylis species, having a distinctive labellum that is larger than the lateral sepals and petals. In South Australia there are only two species and according to Bates (2011), the distinguishing features between the two
appear to be the leaf, the bud and the labellum. In this picture, the angle of the image does not give a clear view of the labellum (it could possibly be damaged) and of course there is no bud or leaf. It is possible that the pale edges of the dorsal sepal may give a clue to species identification as C. reniformis has mainly darker buds than C. robusta. Obviously Doug was able to identify it from his observations of the other features not present in this photograph.
In summary, one image is not always sufficient for identification. As was discussed on the night, to confirm identification, orchids should always be photographed from more than one angle, including pictures of other parts of the plant.
*In South Australia, Pterostylis foliata is a possible exception as it has no obvious lateral orifice.
References
Jones, D.L., T. Hopley, S.M. Duffy, K.J. Richards, M.A. Clements & X. Zhang (2006) Australian orchid genera. An information and identification system. CSIRO Publishing: Collingwood, Vic.
Bates, R.J. (2011) South Australia’s Native Orchids. DVD-ROM. Native Orchid Society of South Australia Inc.: Adelaide.
Jones, D.L. (2006) A complete guide to native orchids of Australia, including the island territories. New Holland Publishers: Sydney.
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
Australian Orchids & the Doctors They Commemorate Part 16 of 20
Hereward Leighton Kesteven (1881 – 1964)
A general medical practitioner, medical scientist, zoologist, pioneer of industrial medicine in Australia, and national medical director of the Allied Works Council during World War II.
Orchids
Dendrobium kestevenii is the name applied to the hybrid between D. speciosum subsp. speciosum and D. kingianum
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 ……
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
- 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
- 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.
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.
NOSSA 