Orchids in Medicine?

Question: Are orchids used in medicine?

Answer: Worldwide, some orchids are used medicinally but compared with other families, despite their numerical dominance in the plant world, orchids only contribute a small number of species to medicine.

Orchidaceae is the second** largest Family in the world after Asteraceae which has about 32,280* species whilst the orchids consists of about 27,753 species. In the big picture, their numbers are similar but only 2.32% (619) of all orchids species can be considered medicinal as opposed to 7.17% (2,314) of Asteraceae.

It is worth noting, that only 28,187 (6.48%) of the possible 434,910 species worldwide are recorded as being used medicinally. But of all of the world’s families it is the small Family of Moraceae (Mulberry, Figs & Mallow) that contributes the most. Of its 1,229 species 22.54% are medicinally useful.

 

 Total number species

 

 Percent of species used medicinally

 

 Number of Species used medicinally

 
World wide

434,910

 

6.48%

 

28,187

 
             
Asteraceae

32,280

 

7.17%

 

2,314

 
Orchidaceae

27,753

 

2.23%

 

619

 
Moraceae

1,229

 

22.54%

 

277

Concerning Australian orchids only a handful are known to have been used medicinally such as Cymbidium for dysentery, Dendrobium teretifolium bruised leaves for pain relief and different parts of  Dendrobium discolor as a poultice and for ringworm.

Cym caniculatum drawing

Notes:

**Many sources will state that the Orchid Family is the largest Family worldwide but for the purpose of this article, the information used is from 2017 State of the World’s Plants. Species numbers tend to be a in state of flux as botanists are discovering new and reassessing data.

*All figures in this article are based upon figures found in the 2017 State of the World’s Plants report.

Reference:

https://stateoftheworldsplants.com/ accessed 9 June 2017

https://academic.oup.com/qjmed/article/98/9/625/1547881/The-uses-and-misuses-of-orchids-in-medicine accessed 9 June 2017

 

Q&A: How do I deal with mould in my orchid flasks?

Question:

I have recently been learning about propagating orchid via flasks but I have mould in some of the flasks.

Orchid Seeds in flask with mould
Flask with orchid seeds and mould

There is mould in the flask with orchid seeds and also in the flask with Diuris tricolour in bulbs.  The bulbs are almost ready for deflasking.

Diuris tricolour in flask
Flask of Diuris tricolour (no mould) – these will be deflasked later this year.

 

What can I do?

Answer:

With a home laboratory, no matter how careful one is, mould can still contaminate the jars of agar. If mould occurs when the orchids are still in seed, then the whole jar needs to be discarded.  The seeds will not survive.

With the Diuris flask, as they are almost ready for deflasking, pot them out straight away. This needs to be done within 10 days of the mould appearing. The weather (March, 2017, South Australia) is still a little too warm but if left in the flask, the plants will die.  Potting them out may give them a chance of survival.

When deflasking, it is important to rinse all the agar off the bulbs before potting on as normal. Once potted, it could help to cover the pot with a cut down clear drink bottle with the lid removed. This will allow some air to circulate. Keep the pot in a shady spot.

Diuris tricolour in pot with bottle top cover
Potted Diuris tricolour with protecting bottle cover

Will it survive in the pot? Hopefully it might but at least the plants have a better chance of survival then if left in the flask where it would surely die.

 

Growing Leek Orchids – Is it Possible?

The Native Orchid Society of SA has been involved with the Threatened Orchid Project which is attempting to propagate some of our most threatened orchids.  There has been some success such as Thelymitra epicaptoides (Metallic Sun Orchids) but others are proving elusive.  Marc Freestone, from the Orchid Conservation Project, Royal Botanic Gardens Victoria, is a PhD student who is researching one such difficult to grow orchid genus, the Prasophyllum.

Prasophyllum murfettii sm
Prasophyllum murfettii (Denzel’s Leek Orchid)

To assist with his research Marc has the sent the following request.

CAN ANYONE GROW LEEK ORCHIDS?

South Australia has about 40 species and Victoria about 74 species of the native Leek Orchids, Prasophyllum.  Some are on the brink of extinction.

A major problem hampering efforts to prevent our Leek Orchids from going extinct is that they have proven next to impossible to grow in cultivation.  They have proved extremely difficult, usually not germinating at all, or germinating but then dying soon after.  Occasionally some success has been had (particularly with symbiotic germination) but successful germination trials to our knowledge have so far proved un-repeatable.  Working out how to grow Prasophyllum is critical for the survival of many species at risk of extinction across southern Australia.

To try and change this, I will be studying Prasophyllum and their relationships with symbiotic mycorrhizal fungi.

But I need your help!

I am wanting to hear from as many people as possible who

  • have tried (either successfully or unsuccessfully) to grow Leek Orchids or the closely related Midge Orchids (Corunastylis).
  • have observed Leek Orchids (or Midge Orchids) recruiting from seed in the wild.

If you can help, or know of anyone who might be worth talking to, please contact me at: marc.freestone@rbg.vic.gov.au or 0428 304 299.

(Funding and support for this project: Australian National University, Federal Government National Environmental Science Programme, Royal Botanic Gardens Victoria, University of Tasmania).

I would encourage people to contact Marc with whatever information that you have, no matter how insignificant you may think it is.  Every little bit helps including unsuccessful attempts.

His eventual aim is to be able to work out how to grow them reliably from seed in cultivation.

When do orchids flower?

This is one of the most commonly asked question.

The short answer is that in South Australia there will be potentially an orchid flowering somewhere in any month of the year but the caveat is that in certain months specifically December, January, February, and March it is very difficult to find any as there are only a few flowering species and most of them are restricted to localised/sensitive sites.  The flowering times for the highest number of species occur in winter and spring with October being the most prolific month for flowering.

 

chart-south-australian-flowering-times

To see how this varies across the state for the individual regions see the charts below.

Another is question “Will I find orchids when I visit a particular park on a particular day?” is not such an easy question to answer because it DEPENDS on so many different factors.

The timing of the rains affects the flowering time, for instance, Autumn orchids appear about 6 – 8 weeks after the first autumn rains.  Normally the South East is the best place but this year the lower South East did not have a good flowering due to the storms and associated cold with the wet conditions.

Pollination affects the likelihood of finding flowers.  Flowers remain open until pollination occurs.  If the pollination is delayed the flower will be on display for a longer time until it runs out of energy and naturally shrivels up.  To illustrate this NOSSA visited Scott Creek Conservation Park one day and there was a beautiful display of sun orchids along with several spider orchids but on a visit to the same site one week later, there were hardly any flowers left.  Many had been pollinated as was evidenced by the swollen capsules.

So as a rough guide click here for the species flowering times of South Australian Orchids and here for month by month information.  This data is based upon information found in the 2011 South Australia’s Native Orchids disk.

For detailed information, it is necessary to consult with someone who knows the orchids in the area but it may not always be easy to find such a person.  In which case, contact NOSSA and we may be able to, through our network, find someone to help.

sa-regions-flowering-times-copy

 

Leptoceras and Leporella – Why are they in different genera?

QUESTION: Are there more than one species called Hare Orchid? This one [Leporella fimbriata] looks different from Leptoceras…?  Why are they in different genera?

 

ANSWER:

Originally they were described the genus Caladenia but as the knowledge information increased other genera were created.  Thus Leporella fimbriata was put into Eriochilus, as Eriochilus fimbriatus (1882), then Leptoceras fimbriata and finally into its own genus Leporella (A S George 1971).  Caladenia menziesii became Leptoceras menziesii.

This does not answer the why of the question which is about classification but Jones (2006) is helpful when he says:

“Plant classification systems rely on interpreting and measuring the features in one group of plants and comparing these with another group, either seeking difference or similarities.  Studies in orchids are usually biased heavily towards features of floral morphology but recent studies have revealed the importance of vegetative features in the roots, stems and leaves.  The most successful classification system is one that is balanced and based on a wide range of vegetative and floral features.”  To add to this list is the molecular studies being done on orchids.

This means the authors advocating change need to clearly show why a name change and/or a new species is warranted.

For instance, Fitzgerald gives the following reason for not including Leporella fimbriata in the Caladenia genus

“Leaves much more frequently observed than flowers.  It is with great reluctance I depart from the naming in ‘Flora Australiensis’ [author Bentham, 1863 – 1878], but I cannot concur with the inclusion of this with Caladenia, and have place it in Lindleys’ Leptoceras for the following reasons: Leaf or leaves not those of Caladenia.  In Caladenia I have never seen more than one leaf, always thin and usually hairy; in this plant leaf thick, hard and shining, occasionally two.  In Caladenia tubers are generally numerous, in L. fimbriata I have only observed one.  The labellum, is without the characteristic glans and is not of the form obtaining in Caladenia, the stigma is very different in form being triangular and deep sunk, the upper parts overhanging, not oval and shallow; and the flowers have the peculiarity of drying and continuing in a state hardly to be distinguished from the fresh flowers long after the seed has been shed.  It approaches C. menziesii only (so far as I can see) in having erect linear-clavate petals, in which C. menziesii is itself peculiar, L. firmbriata seems to come near to Eriochilus than to Caladenia but differs from it again” Quoted from Emily Pelloe Western Australian Orchids 1930

Concerning Leptoceras menziesii, Bates & Weber have made the following statement:

“True Caladenias have hairy scapes and hairy leaves.  (C. menziesii now believed to belong to a separate genus is glabrous)”.

Even though they are not Caladenia, why not have them in the same genus for both have glabous (without hairs) leaves, more leaves than flowers, erect spathulate (spoon shaped) glandular petals, colony forming, similar distribution.

Leporella fimbriata  in patch
Leporella fimbriata – note the absence of leaves and the dry sandy conditions [Photo: R Lawrence]
Leptoceras menziesii in patch
Leptoceras menziesii – note the abundance of leaves [Photo: R Lawrence]
There are similarities.  In fact, Bates (2011) calls them sister genera but despite the similarities there are enough differences to recognise them at genus level at present including “different flowering times, different mycorrhizal fungi associations and different pollination” some of which are detailed in the chart below.

 

Feature Leptoceras Leporella
Pollination Strategy Strategy unknown

Native Bee

Strategy pseudocopulation

Winged male ants (Myrmecia urens)

Myrmecophyte – lives in mutualistic association with colony of ants
Labellum Curved white with red stripes

Has calli

Wider than longer, purple and green

Has no calli

Flowering Time Spring (September to November) Autumn (March to May)
Habitat Shaded sites – moist gullies; scrub, heath, woodland and foret Open sites – acid sands, light scrub, stringybark
Leaf Emergence Leaves emerge before flowering Leaves emerge after flowering

 

Leptoceras menziesii (Rabbit Ears Orchid)
Leptoceras menziesii (Hare Orchid or Rabbit Ears Orchid) after a fire, [Photo: R Lawrence]

REFERENCES:

https://en.wikipedia.org/wiki/Myrmecophyte accessed May 13 2016

http://www.flora.sa.gov.au/cgi-bin/speciesfacts_display.cgi?form=speciesfacts&name=Leporella_fimbriata accessed May 13 2016

http://www.flora.sa.gov.au/cgi-bin/speciesfacts_display.cgi?form=speciesfacts&name=Caladenia_menziesii accessed May 13 2016

Pelloe E, Western Australian Orchids 1930

Bates R & Weber J, Orchids of South Australia, 1990

Bates R Editor, South Australia’s Native Orchids 2011

Martin A, The Vocabulary of Orchids: an Amateur Perspective 2005

Rogers R, South Australian Orchids 2nd Ed 1911

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

Are there any orchids growing in the desert?

Think of deserts and the image is that of a bleak barren landscape with little to see but this is not so.  The conditions are harsh but there is a myriad, though not an abundance, of hardy fauna and flora if one but looks closely.

But concerning orchids – No orchids have been found in true deserts…..  They also appear to be absent from the arid mountains of the far north-west, or at least no-one has ever found orchids there.

Orchids need moisture and so they do not grow on unstable soils such as dry sand-hills, gibber plains or the many saline areas of the far north but on the desert fringes there are micro-climates where the moisture, humidity and soil structure is  just right (to quote Goldilocks) for orchids.  This micro-climate is created by [s]hrubland  [which] is … [an] … important dryland orchid habitat. Besides providing shade and shelter for the orchids, shrubs like the many species of wattles, Acacia and hop-bush Dodonea drop fine leaves which help to hold the soil together and slowly break down into humus rich with nutrient and water storing capability. These shrublands usually form in soils too dry or shallow for trees. Orchids of course have no need for deep soils as they are shallow rooted. 

Robert Bates Semi-arid Shrubland.jpg
Semi-arid Shrublands, Flinders Ranges

Of the five desert botanical regions, the Eastern region contains the most number of species with over a dozen species.

Botanical Regions Map
Colour added to indicate the desert regions (in red)

Orchids of the Eastern Region – this region is from the east of the Flinders Ranges to the New South Wales border and includes the Olary Spur and Lake Frome.

Arachnorchis toxochila – Dry Land Spider Orchid or Bow Lip Spider Orchid.
Corunastylis tepperi – Mallee Midge Orchid
Diplodium robustum – Common green shell-orchid.
Hymenochilus pagophilus – Mountain Shell-orchid
Microtis eremaea – Desert onion orchid
Microtis frutetorum – Common woodland onion orchid.
Oligochaetochilus bisetus species complex, Rusty rufous-hoods

Oligochaetochilus sp. Blue-bush Plain – Blue Bush rufous-hood (O. bisetus complex)

Oligochaetochilus sp. Outback – Outback rufous-hood (O. bisetus complex)

Oligochaetochilus cobarensis – Little desert rufous-hood
Oligochaetochilus sp. Crossed Sepals Bibliando rufous-hood. (O. hamatus complex)
Oligochaetochilus sp. Bimbowrie Bimbowrie Rufoushood (O boormanii complex)
Oligochaetochilus linguus – Swept-back Rufoushood

Oligochaetochilus sp. Old Boolcoomatta Large-lip rufous-hood (O. linguus complex)

Oligochaetochilus sp. Quartz – Quartz hill rufous-hood (O. linguus complex)

Oligochaetochilus sp. Slender desert – Slender Desert rufous-hood (O excelusus complex)
Undescribed not within any other Oligochaetochilus complex

Oligochaetochilus sp. Canegrass – Desert Sand-hill Orchid.

Oligochaetochilus sp. Oratan Rock – Diminutive rufous-hood

Oligochaetochilus sp. ‘Mt Victoria Uranium Mine’ – Uranium rufous-hood

Prasophyllum odoratum – Scented Leek-orchid

Prasophyllum sp. Desert Desert Leek-orchid (P. odoratum complex)

The Gairdner-Torrens region includes, besides the salt lakes it is named after, the Gawler Ranges and the southern part of the Great Victoria Desert.  Though not as many species as the Eastern region, it contains some different species including a Sun Orchid.

Thelymitra megcalyptra
Thelymitra megcalyptra
Arachnorchis interanea – Inland Green-comb Spider Orchid
Arachnorchis toxochila – Dry Land Spider Orchid or Bow Lip Spider Orchid.
Hymenochilus pagophilus – Mountain Shell-orchid
Hymenochilus pisinnus – Tiny Shell-orchid
Jonesiopsis capillata – Pale Wispy Spider Orchid
Linguella sp. Hills nana – White haired little-greenhood.
Microtis eremaea – Desert onion orchid
Oligochaetochilus ovatus – Ovate Lip Rufoushood
Oligochaetochilus xerophilus – Desert rufous-hood
Prasophyllum sp. Desert Desert Leek-orchid (P. odoratum complex)
Thelymitra megcalyptra – Scented or Dryland Sun Orchid

Third of this group is the Nullabor region.  Consisting of flat treeless limestone plains, this area, surprisingly, has two species both of which have been found close to the coast.

Urochilus sanguineus – Maroon banded greenhood
Corunastylis sp. Intermediate – Halbury Midge Orchid (C. rufa complex)
Urochilus sanguineus
Urochilus sanguineus

The final two regions Lake Eyre and North-Western contain the vast expanses of desert of the far north of South Australia.  Definitely not a place to find orchids yet one specimen has been collected from each of these two regions.

Oligochaetochilus sp. Everard Range (L. Scott 173), Mimili Orchid (possibly O. woollsii complex) from North-Western Region.

Oligochaetochilus sp. Gammon Range (O excelusus complex) from the Lake Eyre region.

It is unusual to find orchids in the desert because they only grow when there have been good winter rains which isn’t very often.  But nevertheless, here in South Australia we have over 20 possible species – an astonishingly high number for such a harsh area!

Reference:

Bates R J ed, South Australia’s Native Orchids, 2011 Native Orchid Society of South Australia

Map adapted from Flora of South Australia, Fourth Edition, 1986

 

 

Do Any Orchids Grow Near The Sea?

Orchids are found in a wide range of habitats.  One such habitat is the littoral zone or more simply the seaside.  The following information is taken from the NOSSA’s CD/DVD South Australia’s Native Orchids 2011.

The Littoral Zone

Many orchid species have a linear distribution following the coastline. Here on the leeward side of sandhills the air is usually moist and mild, few frosts occur so close to the sea and sea-fogs in winter will cause water to drip into the sand which easily soaks up both the moisture and the extra nutrients provided by sea-spray. Some of the best known coastal orchids include the gnats Cyrtostylis robusta, pink fairies Caladenia latifolia, coast onion-orchids, Microtis arenaria and coastal helmet orchids Corysanthes expansa as well as C. despectans. All of these are colony forming species, mostly because the windblown sand would soon cover ‘single plant’ species which start to appear after the second line of dunes.

Coastal species can be a few kilometres from the sea but there are several that grow either at the high tide mark, within sight or sound of the sea or in coastal dunes. Apart from the ones already mentioned above, the following are some others that can potentially be found within sight and sound of the sea.

  • Acianthus pusillus (Mosquito Orchid)
  • Arachnorchis cardiochila (Thick Lipped Spider Orchid)
  • Arachnorchis fragrantissima (Scented Spider Orchid)
  • Arachnorchis fuliginosa (Coastal Spider Orchid)
  • Arachnorchis sp Brown Bayonets (Port Lincoln Spider Orchid)
  • Bunochilus flavovirens (Coastal Banded Greenhood)
  • Bunochilus littoralis (Lake Saint Clair Banded Greenhood)
  • Caladenia sp Selfing Coastal Dunes (Little Dune Fingers)
  • Corunastylis nigricans (Port Lincoln Midge Orchid)
  • Diuris orientis (Wallflower Orchid or Bulldogs)

    Diuris orientis
    Diuris orientis (Wallflower Orchid)
  • Diplodium erythroconchum (Red shell Orchid)
  • Glossodia major (Waxlip or Purple Cockatoo Orchid)
  • Leptoceras menziesii (Hare Orchid, Rabbit Ears)

    Leptoceras menziesii (Rabbit Ears Orchid)
    Leptoceras menziesii (Rabbit Ears Orchid) after a fire
  • Prasophyllum elatum (Tall Leek Orchid)
  • Prasophyllum litorale (Vivid Leek Orchid)
  • Prasophyllum sp Late Coastal Dunes
  • Pterostylis cucullata (Leafy Greenhood)
  • Pterostylis curta (Blunt Greenhood)Pterostylis curta Labellum and column 92RL
  • Thelymitra antennifera (Rabbit Ears; Lemon Sun Orchid)07 JB T antennifera sm

Unfortunately, where there has been settlement, it is now unusual to find these species so close to the sea.

How Much Fertilizer Do I Need For My Australian Terrestrial Orchids?

The short answer is very little to none at all. As long as there is some organic matter in the soil mix terrestrial orchids will grow and flower without added fertiliser.

For fungus dependent orchids, such as Caladenia, a fresh layer of leaf litter added in summer to the top of the pot is all that is required. These orchids are seldom repotted.

Growers who show their non fungus dependent orchid plants for judging want strong superior plants.  They add a pinch of blood & bone fertilizer to each pot during the annual summer repotting. Vigorous orchids like the colony forming greenhoods will respond to weak foliar feeding in the early growth stages, (April to July).  If fertilizing is overdone the plants can burn or produce multiple flowers that grow into one another and ruin the spectacle of flowers.

Other factors are more important than fertilizer.  Strong light in winter, constantly moist potting mix, excellent drainage,  good air movement and a pest free environment are more important.

Thelymitra plants in pots
Thelymitra (Sun Orchids) in cultivation
Pot of Caladenia latifolia cultivated by Les Nesbitt
Caladenia latifolia in cultivation
Diplodium robustum - one of the cauline greenhoods
Diplodium robustum – one of the cauline greenhoods

When do I stop watering my Greenhoods?

This was the question posed to Les Nesbitt at the September monthly meeting.  Later there was some further discussion, of which see below:

When do I stop watering my Greenhoods?

The short answer is when the leaves go yellow and start to die off, usually in October- November. Allow the pot to dry out completely to dry up the roots and old tubers so that they do not go mouldy and rot the new tubers.

Australian terrestrial orchids form tubers underground. The mature plant dies back at the end of the growing season and enters a period of dormancy which for South Australian terrestrials is over summer.

A general principle of watering is to match the watering to the rainfall pattern. Whilst there is minimal rain over summer, when dormant tubers are in pots it is important to not let them stay dry for months and become desiccated. A light sprinkling every week or two is sufficient.

Unicode
Pterostylis ‘Nodding Grace’ This is an hybrid between P. nutans and P. curta. Obviously it is not time to stop watering.

When do I start watering again? 

For the cauline group (Diplodiums) from South-eastern Australia start watering at the end of January as the tubers are starting to shoot by then. For other greenhoods start light watering in late February and gradually increase the water until shoots appear usually in March-April. Do not let the pots dry out once leaves are visible.

Diplodium robustum - one of the cauline greenhoods
Diplodium robustum – one of the cauline greenhoods. Note difference the between the leaves of the non-flowering rosettes and the flowering plants.

Other cultivated Australian terrestrial orchids require a similar watering regime although leaves of some appear later in May or June.

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.