September Terrestrial Orchid Culture Notes

Continuing Les Nesbitt’s notes from the NOSSA Journal, this month he reminds us that not only is it a busy month but it is the month of the NOSSA Spring Show.

September is the busiest month of the year in the terrestrial house. apart from orchid shows every weekend there are numerous tasks to perform. The days are getting longer at a rapid rate. Day length increases by 2 hours in the 6 weeks from the 1st Deptember. Equinox is about the 21st September.

Early Spring weather is changeable from cold, windy & wet to warm & sunny. Give plants as much sun as possible as new tubers are developing rapidly. Hand watering may be necessary if there is no rain so get the hose out of winter storage. Do not let the post dry out this month. There are lots of flowers everywehere. Take photos as some flowers are fleeting and may only last one day. Different pollinators are about for the more colourful terrestrials that start flowering in spring.

Prepare your flowering plants for the NOSSA Spring Show. It is fun to put in a display even if you only have one or two plants. You learn a lot from other growers. We certainly need new exhibitors each year. Seek new species to add to your collection at the NOSSA Spring Show. Be there at 10am Saturday morning for the hard to get species which are always in short supply.

Spring is an ideal deflasking period but get it done in the first 2 weeks to give sufficient growing time to harden the plants and for tiny seedling tubers to form before the summer dormancy.

Notes on Tuber Removal

Start tuber removal after the middle of the month. In a wet year you may have to move pots under cover a week earlier to dry out a bit before knocking them out. working with mud is a real pain and not recommended. Use this method to propagate the slow multiplying terrestrials that are amenable. those recommended for slow multiplying are Diuris (punctata & behrii), and rufa group Pterostylis (cycnocephala & biseta).

Knock out the pot and carefully remove most of the soil from the plant. Find the new tuber which is usually whiter smoother than the old tuber. Hold the junction of the old tuber and plant stem firmly with one hand and grasp the new tuber with thumb & finger of the other hand. Twist & pull the new tuber which will separate from the plant. If the old tuber and leaves break apart you have stuffed up. Repot the plant & old tuber and water the pot. The new tuber can be buried in the same pot or potted up separately in another pot. Keep the plant watered for at least six weeks or as long as the leaves stay green. The plant may form one or two small new tubers before going dormant. In January you can repot and see how well the method worked.

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Monthly Terrestrial Orchid Culture – August

With Spring on the way, things are starting to change in the Orchid House. Here are Les Nesbitt’ notes from the August Journal 2019 Vol 43 No 7

Terrestrial Culture – August

The days are getting longer now, noticeably so after the middle of the month. When the clouds clear, the sun is stronger & higher in the sky. Temperatures increase and growth speeds up. Lots of buds are developing so there is plenty to see in the orchid house. The greenhoods are a feature with Pterostylis curta, nutans, pedunculata and their hybrids are all flowering.

Pests become more active. Look out for aphids on flower stems. Depending on the season deflasking can start after the middle of the month if a sunny and dry Spring is forecast, otherwise wait until September.

The NOSSA Spring show is only a month away. Start preparing your specimen pots for the display. Any spare pots can be sold on the trading table. There are never enough terrestrials on the trading table at the show to meet the demand.

Photograph your orchids when the flowers are at peak condition. Then hand pollinate a flower or two to get seed for the NOSSA Propagation Workshop or for sowing around mother plants next autumn. Prepare two pots of each species, one for showing and one for seed.

 

How to hand pollinate.

Look closely at the flower column to see the positions of the pollen and the stigmatic surface. Flowers can be self-pollinated if there is only one. Fatter pods with more viable seeds result if two plants of the same species are cross pollinated. That is transfer the pollen from one flower to a flower on another plant. Cross pollination mixes the gene pool to prevent inbreeding. Use a toothpick or a she-oak needle to touch the pollen which will stick to the wood. Wipe the pollen across the stigmatic surface of the other flower and the job is done.

If pollination is successful, the flower will collapse in a few days and the ovary will start to swell. For greenhoods the stigmatic surface is halfway up the front of the column. Remove the front of the flower and the lip so you can see what you are doing. Greenhoods have yellow pollen. For Diuris and Thelymitra the white pollen is hidden behind the sticky stigma. Caladenia have yellow pollen under flaps at the top of the column. Stroke upwards to open the flaps as would an insect backing out of the flower. The stigma is a hollow sticky depression just below the pollen. You will have to tip the flower right back to see it.

Monthly Terrestrial Orchid Culture – July

Continuing Les Nesbitt’s articles from the NOSSA Journal, this month’s (Vol 43 No 6 July 2019) is a relaxing time.

Midwinter is cold and cloudy most days. July is often the wettest month as well. A good time to sit by the heater and read orchid books or search the internet as you plan future activities. Tidy up your records and draw up a wanted list of terrestrials to purchase or swap. Activity in the lab continues with seed sowing and replating. Deflasking should wait until spring as tiny seedlings rot away if planted out in winter. Pots showing any signs of rot should be moved out of the
rain to dry off.

Not a lot to do in the orchid house except observe your orchids and watch for pests that are always looking for a feed. Growth will be slow. Give plants as much sunlight as possible. The very first seedling leaves may appear this month around mother plants. Give yourself a pat on the back if you see any seedlings. More may show in August & September.

Corybas flower this month and do not mind being cold and wet. Corybas flowers will shrivel up if the surrounding air is dry. Mist them daily or place a clear cover over the pot & the flowers will last for weeks. A tall plastic sleeve around the pot or an upturned glass bowl can be used.

Orchid clubs hold their Winter shows this month. Check them out for additions to your collection.

Caladenia plicata – April Winning Photograph

Shane Grave’s winning photograph for April was the spring flowering Caladenia plicata which is endemic to the South West of Western Australia.

Caladenia is a very large genus with over 330 species, 39 of these currently unnamed. In addition, there are 58 named subspecies and varieties. Caladenia plicata would belong under the subgenus Calonema or the segregate genus Arachnorchis which, although not generally recognised by State herbaria is commonly accepted by many amateur enthusiasts. Yet even this subdivision is still large with 192 species. As a result, some authors have created further groups/complexes, for example C. dilatata complex, C. longicauda complex, etc. However, according to Andrew Brown, C. plicata doesn’t seem to fit neatly into any of these categories, although David Jones does include it within the clubbed spider orchids.

Various authors consistently refer to the labellum as being unusual. In Fitzgerald’s formal description (1882) he states that the labellum tip is “recurved so as to become plicate and touch the under surface of the disc”. Plicate means to fold. The labellum tip of many other Arachnorchis species are known to curl under but none fold under in the way that this species does. The sharp fold with the spreading horizontal fringed margins (edges) combined with a central band of tall dense calli (wart-like structures) gives a distinctive shape reminiscence of a crab, hence the common name Crab Lipped Spider Orchid. The effect of this is best seen from a front, rather than a side, view.

The very mobile labellum is sufficient to identify this species, but it is also possible to identify when in bud “due to the prominent short osmophores (clubs) on the sepals”. The sepals narrow halfway along to form thick brown clubs and when the flower is open both the lateral sepals and petals are downswept. This is clearly seen in Shane’s photograph.

Finally, for those interested in pollination, it is pollinated by an undescribed male thynnine wasp of the genus Zeleboria. This has been captured on video https://ars.els-cdn.com/content/image/1-s2.0-S0960982217306310-mmc6.mp4

 

Thank you to Andrew Brown for assisting me with this article.

References:

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

Brown A, personal communication

Caladenia accessed 24 May 2019

https://en.wikipedia.org/wiki/Caladenia

Caladenia plicata Wikipedia accessed 24 May 2019

https://en.wikipedia.org/wiki/Caladenia_plicata

Haiyang Xu et al Complex Sexual Deception in an Orchid Is Achieved by Co-opting Two Independent Biosynthetic Pathways for Pollinator Attraction 2017

https://www.sciencedirect.com/science/article/pii/S0960982217306310

Jones DL, A Complete Guide to Native Orchids of Australia including the Island Territories 2006

Jones DL, et al, Australian Orchid Genera CD-ROM 2008 CSIRO accessed 24 May 2019

https://www.anbg.gov.au/cpbr/cd-keys/orchidkey/html/genera/Arachnorchis.htm

Pelloe, EH, West Australian Orchids 1930

http://gutenberg.net.au/ebooks04/0400681h.html#page50

Orchids of South-West Australia website

http://chookman.id.au/wp_orchids/?page_id=2424

 

 

Monthly Terrestrial Orchid Culture – April

The following article by Les Nesbitt is taken from the Native Orchid Society of South Australia Journal, April 2019, Volume 43 No 3

Terrestrial Culture – April
Les Nesbitt

The days and nights are cooling down, evaporation rates are dropping and pots take longer to dry out so decrease the watering. If in doubt wait another day before watering. Regular rain usually begins around Anzac Day. There is nothing like a good rain to make terrestrial leaves pop up almost overnight. A few early flowers are out this month – Eriochilus species and possibly Pterostylis truncata. Keep up the pest control and pull out weeds while they are still small.

Sow seed on pots around mother plants of fungus dependent orchids this month. Mix seed & fine sand together to avoid wasting precious seed. A pepper shaker helps spread the seed evenly. Water gently to wash the seed into the mulch.

April is a good month to deflask terrestrials. Seedlings need to establish & harden up before winter so get deflasking completed by the end of April. Check out flask suppliers for that special species. The next deflasking opportunity is early spring.

Deflasking Terrestrial orchids

Prepare a suitable soil mix for the orchid to be deflasked along with labels & sheoak topping. Use the same mix as for adult plants.

Select a flask with strongly growing seedlings, preferably with small tubers but plants without tubers are OK. Remove the flask lid and tip the mass of plants and agar into a fine sieve. If you are nervous remove clumps of plants from the flask with tongs. Try to minimize breakages. The junction of leaf & tuber is very weak. Over a sink or lawn, use a jet of water to wash away the agar leaving clean seedlings behind.

Fill a pot with mix to within 2 cm of the rim and tamp down. Select small clumps of seedlings and stand them around the edge of the pot. Insert a label with the appropriate info as this pot will not be repotted for 2 years. Pour a handful of mix into the centre of the pot and gently squeeze mix out around the seedlings just covering the bases but not burying the leaves. Add more mix if necessary. Tamp down the mix in the centre of the pot. Add a layer of chopped sheoak needles. Water gently to settle the mix around the seedlings.

The pot can go into the shadehouse with other terrestrial pots although it helps to keep all the seedling pots together in a sunny place with good air movement. Ensure the pot does not dry out. If kept too wet the seedlings may rot. If the seedlings establish and grow strongly they can remain in the shadehouse over winter. At any sign of rot move the pots out of the rain under cover and water by standing the pot in a saucer of water.

Next dormant season as soon as the leaves have died down, add more mix to completely fill the pot. This helps to protect the tiny seedling tubers from drying up in the heat of summer. After the second growing season the tubers should all be large enough to find easily at repotting time.

Thelymitra malvina (Purple Tufted Sun-Orchid)

2019 Winning Photograph Competition

Welcome to our first competition for 2019. For February we had five entries which included Pauline Meyers’ Prasophyllum species from Western Australia, Lindy McCallum’s Glossodia major  and Leptoceras menziesii, Lisa Incoll’s Thelymitra antennifera.

1902 SM Pauley Thelymitra malvina

The winner was Rob Pauley’s photograph from the south east of Thelymitra malvina (Mauve Tufted Sun Orchid) which is found in only a few places in the South East but does occur in Victoria, New South Wales, Queensland, Tasmania and even ‘across the ditch’ in New Zealand where it is considered “an Australian species now established in the North Island”.

According to the Atlas of Living Australia, it is endangered in Victoria, South Australia,  Tasmania; of Least Concern in Queensland and there is no listing for New South Wales.

This species has been included in both the T. nuda and T. pauciflora complex for, as Jeanes has observed, it has characteristics of both complexes such as the smaller flowering forms are self-pollinating, and the larger flowering forms are insect pollinated

Though the common name, Mauve Tufted Sun Orchid, indicates that its most distinctive feature are the purple tufts on the post anther lobe, it is possible to find them with white tufts and there are other species that have purple tufts (eg in SA T. azure and T. occidentalis may have purple tufts but it is obvious from their other features that they are not at all similar to T. malvina).  There are no other closely similar species in South Australia, but on the other hand, in the eastern states, it can be confused with Thelymitra atronitida, so it is worthwhile considering some of the main differences between these two.

Although there are no other closely similar species in SA, in the eastern states it can be confused with Thelymitra atronitida, so it is worthwhile considering the differences

T. malvina T atronitida
Stem 3 sterile bracts 2 sterile bracts
Height 25 – 75 cms 30 – 50 cm
Flowers Slightly larger (but can have smaller flowers) Smaller flowers
Inflorescence 3 – 25 usually loose 2 – 8 ( – 16)
Column Reddish to dark brown with yellow apex Glossy black with yellow apex
Post anther lobe Moplike tuft of pink or mauve (rarely white) trichomes Moplike tuft of white trichomes (hairs)

Across the country, there is some variations of flowering times with New South Wales having the longest flowering time from August to November and South Australia along with Tasmania having the shortest of October and November.

REFERENCES

Bates RJ, 2011 South Australia’s Native Orchids, electronic

Backhouse G, Bush Gems, A Guide to the Wild Orchids of Victoria, Australia, 2016, electronic

VicFlora, https://vicflora.rbg.vic.gov.au/flora/taxon/0de4b1c5-3f1f-43ea-9464-c713a12d5758 Accessed 6 March 2019

VicFlora, https://vicflora.rbg.vic.gov.au/flora/taxon/748b23b6-4779-4a93-89fc-8ec2a8b05a06  Accessed 6 March 2019

Atlas of Living Australia, https://bie.ala.org.au/species/NZOR-4-76548  Accessed 6 March 2019

New Zealand Native Orchids, https://www.nativeorchids.co.nz/Descriptions/Thelymitra_malvina.html Accessed 6 March 2019

Jeanes J, 2013 An overview of the Thelymitra nuda (Orchidaceae) complex in Australia including the description of six new species https://www.rbg.vic.gov.au/documents/MuelleriaVol-31-p3-Jeanes-PDF-Accessibility.pdf Accessed 6 March 2019

Natural Value Atlas, https://www.naturalvaluesatlas.tas.gov.au/downloadattachment?id=14596  Accessed 6 March 2019

Monthly Terrestrial Orchid Culture—March

As stated last month, this is the second in the series of terrestrial culture notes for growing orchids in Adelaide.

Terrestrial Culture—March

Les Nesbitt

The growing season is underway although much of the activity is underground out of sight early in the month. Repotting should be completed by now. Repotting tubers with long shoots is a tricky business requiring very gentle handling. Broken shoots and the death of some plants can result. It is better to leave them until next summer.

The weather can be hot up until equinox on about March 21st.  Be aware that autumn is a time of rapid change. Day-length decreases by 2 hours in the 6 weeks from the 1st of March. Our orchids respond to the longer cooler nights faster than we do. All pots should be in their growing positions for the coming winter. Increase watering in March so that by equinox the mix is damp right through to the bottom of the pot. The first Eriochilus cucullatus flowers are usually open by the last day of March with the majority blooming in April. The buds resemble a grain of wheat when they first emerge.

Eriochilus collinus
Eriochilus collinus (syn Eriochilus sp Adelaide Hills, Eriochilus aff cucullatus)

Thrip can be a major problem this month. Thrips love to suck on the flowers and will cause the flowers to shrivel up in a day or two. If using a pressure pack fly spray to kill thrips, hold the can at least half a metre away or you can freeze the flowers with the propellant. Repeat the spray every few days.

Pull out any weeds that germinate while they are still small. The early Greenhoods will be showing leaves and some of the blue tag Diplodiums may be showing buds. The Greenhoods will like a weak soluble fertiliser sprayed on their new leaves as they develop.

Deflasking can be done after equinox. April is the best month to deflask terrestrials as it is cooler and more humid with enough sun to harden the leaves before the cold and damp of winter. Flasks are often the only way to get the slow multiplying terrestrial orchids. Seedlings in flask that have tiny tubers establish more successfully.

Diuris tricolour in flask

Remove the second layer of shadecloth at the end of the month or first week in April. Keep up the night time hunts for pests which get more active as the nights cool.

Autumn is a good time to build or extend a terrestrial growing area. A terrestrial house should be sealed to keep out birds and animals and have shadecloth or wire mesh sides to allow the breeze to move through. I prefer a roof of angled 50% shadecloth. Other growers use a solid roof of plastic sheeting. A solid roof means you have to water your pots by hand, which is more work. It is very important that winter sun reaches your plants so site the shadehouse away from the winter shadows of buildings, high fences and evergreen trees. Galvanised mesh benching about 750 mm high will deter slugs and snails and is a convenient height for observing the pots.

food healthy nature forest
Photo by PhotoMIX Ltd. on Pexels.com

Waiting for the rain …

Last year we waited for the rain. The rain heralds the start of the orchid season. Last year the season was dry, very dry. It was below average and it was hot.

So how did the orchids fare in the Adelaide Hills? The start of the season was slow with our first field trip not being until May 26 because of the lack of rain.

At the time, the smallness of the plants was noticeable with one specimen of flowering Leporella fimbriata standing no more than 2 cms. Normally  the flower stem can be up to 25 cms tall. This trend of smaller plants continued throughout the year.

The following two photographs show the difference in size.

Small Leporella fimbriata
A miniscule Leporella fimbriata near an ant nest

Leporella fimbriata sm

And on January 28, we came across the smallest flowering Dipodium pardalinum that we’d ever seen. Normally, this genus can grow up to about 100 cms in height but this one barely reached above the height of Robert’s shoe, ie, about 10 cms. True this was an exception but overall there not many plants, and even they were spindly and small in comparisons with previous years.

Below are two photographs illustrating the size difference

Small Dipodium pardalinum
A very tiny Dipodium pardalinum

Dipodium roseum
An average sized Dipodium

So what is the outlook for orchids for 2019? That will depend upon the rains.

When does the orchid season get going? Again that depends upon the rain but expect to see the autumn orchids about six to eight weeks after a good rain episode.

So we wait for the rains ….

Genus Plumatichilos

This week’s blog is from the Journal of the Native Orchid Society of South Australia, Volume 42 No 8. Leo Davis has been doing a series of articles aimed at helping members learn how to identify the orchids.

This article is about Plumatichilos, one of the segregate genera of Pterostylis. It has an unique labellum which sets it apart from the other Greenhoods. Leo wrote this article soon after David Jones named them in the Australian Orchid Review.  Will these names be accepted or not is a matter of waiting and seeing but it should be noted that they have been in manuscript form for many years. At the time of writing, they are not in the South Australian eflora.

Both the species discussed in Leo’s articles are from the Plumatiochilos plumosum complex or group.

Plumatichilos sp. Mallee Bearded Greenhood =Plumatichilos multisignatus

Plumatichilos sp. Woodland Bearded Greenhood = P. foliaceus

Unless otherwise noted, all images are Leo Davis.

Genus Plumatichilos.

Back in 1990 Bates & Weber placed all greenhood orchids in genus Pterostylis(1. pp118-143) where some of you and all Australian State Herbaria and certainly Janes & Duretto (3. pp260-269) would have them still be.  In 2001 Szlachetko erected the genus Plumatichilos.  In his Guide(4. pp286-339), Jones divided the greenhoods into 16 separate genera, these in two groups, each of eight genera.  One group all have the lateral sepals directed downwards (including Bunochilus and Urochilus) and the other eight all have them directed upwards (deflexed, as in Diplodium and Pterostylis).  Even those of you who reject the splitting and creation of the extra genera will concede that those placed in Plumatichilos, which have downward directed and partly fused lateral sepals (forming a synsepalum), are strikingly different in appearance to any other Pterostylis species.  The most obvious distinguishing features are the unique labellum and the two openings to the galea.

I had known just two species of Plumatichilos, both of which were undescribed.  I could recognise and distinguish them essentially because they grew in very different habitats and locations.  I used Bates’ tag names, Mallee Bearded Greenhood (Plumatichilos sp. Mallee Bearded Greenhood) (3. pp913-4) and Woodland Plumed or Bearded Greenhood (Plumatichilos sp. Woodland Bearded Greenhood)(1. pp915-916).   In recent weeks both (along with two other South Australian species) have been formally described.  They are now, respectively, Plumatichilos multisignatus(5. pp33-35) (Fig. 1) and P. foliaceus(5. pp30-32) (Fig. 2).  But, to a large extent, I still identify them more by the locations in which I find them than, to my eye, clearly discernable physical features.

Fig 1 P multisignatus Fig 2 P foliaceus
Fig. 1. Plumatichilos multisignatus. Monarto. Sept 10, 2012. Fig 2. Plumatichilos foliaceus. Para Wirra. Sept 11, 2013.

I had no idea what ‘barrier trichomes’ were but I saw that Jones listed them as the last of 13 dot pointed characters of genus Plumatichilos(5. p26).  Trichome simply means a hair growing from a plant epidermis.  They can be unicellar or multicellular and branched or unbranched.  The ‘barrier’ refers to its capacity to block and direct a pollinating insect to an exit path that puts it in the right posture to transfer a pollinium to the stigma (sticky receptive female part of flower).

Fig 3 Bunochilus prasinus June Niejalke Janes & Duretto, who reject the splitting of genus Pterostylis, divide it into two subgenera using the absence (subgenus Pterostylis) or the presence (subgenus Oligochaetochilus) of barrier trichomes on the column wings(3. pp262).  They place what I call Plumatichilos in the section V, Catochilus, of subgenus 2 Oligochaetochilus(3. pp266), and, yes, I see your eyes glaze over.  To them the Adelaide Hills ‘plum’ would be Pterostylis, subg. 2 Oligochaetochilus, Sec. V. Catochilus, species foliaceus.  Learning what ‘barrier trichomes’ are had me go back searching my photo library and I found images of the barrier trichomes in Bunochilus flowers that I had not previously spotted.  I have used and annotated a detail sent to me by June Niejalke. (see Fig. 3).

Fig. 3. Bunochilus prasinus. Sherlock (Type location for the species). Photo by June Niejalke.

As with all ‘true’ Pterostylis, the dorsal sepal and the two lateral petals, of the upside down flowers, are formed into a galea or cap (Fig. 1).  They are fused so closely that it can be hard to discern the join between the sepal and the comparatively small petals, especially in some less clearly striped flowers. (Figs. 1 & 2).

The typical Pterostylis galea has a single opening but in Plumatichilos there are two, a lower one, from which the uniquely formed labellum protrudes (and through which the pollinating male gnats enter) and an upper one (through which the pollinators exit) (4. p335), guided by the barrier trichomes (Fig. 4).  Through this upper opening you can observe the top of the column, including parts of it, the pollinia, the barrier trichomes, column arms and sometimes the stigma.  Two crossed filaments, in front to the pollinia, are column arms.

Fig. 4. Plumatichilos foliaceus. Scott Creek C.P. Sept 2015.

Fig 4 P foliaceus

 

Fig 5 P foliaceus.jpg The labellum (the modified third petal) (Figs 1, 2 & 5) is unlike that of any other Pterostylis sp.  It has a slightly flattened filament having a reddish-brown apical knob and two or three types of hairs along its length.  Jones describes the labellum of P. foliaceus as having three types of hairs(5. p30).  You may be able to see the short white ones (1 mm) at the base of the labellum in Fig. 5.  The longer (5-7 mm) yellow ones along the most of the length of the labellum are easy to see.  I am not sure that I can distinguish the shorter proximal (near point of attachment) yellow ones (1.5 mm).  In P. multisignatus Jones describes just two types of labellum hairs(5. p33) with the white basal ones absent, and two sorts yellow hairs, proximal ones to 1.2 mm and longer ones 5-8 mm.  To my eye, this character, two or three types of labellum hairs, is the only objective, rather than subjective , distinguishing feature between the two species that I regularly observe.

Fig. 5. Plumatichilos foliaceus. Scott Creek C.P. Sept 26, 2015.

In Fig. 5, I think that you can see that the hairs arise, in two parallel rows, not paired, from the sides of the flattened shaft of the labellum filament.

Fig 6 P foliaceus Fig. 6. Plumatichilos foliaceus in early bud. Scott Creek C.P. August 29, 2018.

Another generic character is ‘leaves sessile (no stems), ascending to erect, often with whitish or yellowish interveinal areas.’ (5. p26)  You may need to look very closely, in Fig. 6, to see these ‘windows’, mainly at the bases of the stemless leaves. 

 

References:

  1. Bates, R.J (2011). South Australian Native Orchids, DVD Issued by the Subediting Committee (NOSSA) on behalf of the
    Native Orchid Society of South Australia Incorporated.
    2. Bates, R.J. & Weber. J.Z (1990). Orchids of South Australia, A. B. Caudell, Government Printer, South Australia.
  2. Janes, J.K. & Duretto, M.F. (2010), A new classification for subtribe Pterostylidinae (Orchidaceae), reaffirming
    Pterostylis in the broad sense. Australian Systematic Botany, 23, 260–269.
  3. Jones, D.L. (2006), A Complete Guide to the Native Orchids of Australia, Reed New Holland, Australia.
    5. Jones, D.L. (2018), Six new species of Plumatichilos (Orchidaceae: Pterostylidinae) fromSouth-eastern Australia and a
    new species from New Zealand, Australian Orchid Review 83(4): 26-44.

Other articles about Plumatochilos can be found here and here.

Orchids in the Snow?

It’s Christmas and usually, despite Australia’s hot climate, we associate Christmas with snow and cold but we don’t tend to associate them with orchids. And yet, for Australia we do have not one but two Christmas flowering orchids in snow country, that is, on the isolated sub-Antarctic Macquarie Island, an island where “[r]ain and snow are frequent, with only a few days each year with no precipitation”. Admittedly at this time of the year, being summer it is warmer with an average temperature of 7.9degrees Celsius.

The first species was only discovered in 1978 and not recognised as an unique species until 1993 when it was named Corybas dienemus (syn. Nematoceras diemenum). Previously it had been linked with Corybas macranthus.

The second orchid species is  Corybas sulcatus (syn. Nematoceras sulcatum) and this species, possibly the world’s rarest orchid, has gone travelling. Staff from the Royal Tasmanian Botanical Gardens have manage to collect and amazingly propagate the seed.  Amazingly because orchids, particularly the terrestrial orchids, are difficult to grow. It is now flowering, this Christmas season, but under very carefully controlled conditions in Hobart.

Click here and here to see images and read about this amazing journey.

So Christmas, orchids and snow do go together in Australia, albeit in the far flung island of the south.

Corybas sulcatus (Grooved helmet-orchid) is one of two endemic orchids which occur on Macquarie Island (Photo: Royal Tasmanian Botanical Gardens) Image Source

Reference

https://en.wikipedia.org/wiki/Nematoceras_dienemum accessed 23 December 2017

http://www.antarctica.gov.au/living-and-working/stations/macquarie-island/location/climate-weather-tides accessed 23 December 2017

http://www.antarctica.gov.au/news/2017/sub-antarctic-orchid-shows-true-colours-far-from-home accessed  23 December 2017