Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Thursday, October 08, 2009

Tangle-root Orchid - edited

As I was not satisfied with the photos in yesterday's post, I have added new images which I took today, back out in the bush, when it was less windy.

This is my first post about the Tangle-root Orchid (Plectorrhiza tridentata) I may have mentioned it incidentally before, but I have never had close-up photos before. My fellow Aussie Nature Blogger, Gaye, has written about this Orchid when she found it in the Barrington Tops.

This is an uncommon Orchid up here on top of the Illawarra Escarpment. I had seen one plant here, before, just on the edge of the Robertson basalt caps, but on the lower edges there-of.
Tangle-root Orchid is well named.
This plant is hanging by a single thread of root
suspended from the ferns on the tree branch above it.
Its ball of roots is about the size of a football - but very light.
This plant has only about 7 leaves,
but it is carrying about 12 flowers.
These flowers are clearly honey coloured.
Here is a cropped image,
showing the same plant - just its leaves and flowers
This plant was about 5 metres high.
The flowers are small and hard to see.
Some time ago I was told by Graeme Bradburn of ANOS about another place in my local area (a place with which I was familiar) where he said these Orchids were to be found. Sure enough, after seeing that the one plant I knew about was in flower, I tried the place Graeme had suggested - and there they were.
This was the best image I could obtain, with a zoom lens.
It clearly shows the long spur behind the labellum.
(in this angle it is "above", but structurally, it is behind the labellum)
A closer view of spray of flowers.
Some insect eggs on the leaf at lower end.
Same species, but these ones are green not honey-coloured.
See new image below - which is clearer.
Click to enlarge)

This is one flower very close-up, from the side.
Note how there is a long tube ("spur") behind the labellum.
The dorsal sepal and lateral petals closely shield the column.
(Photo replaced 10.10.09)

Here is a flower, as seen from above.
The white and yellow parts are the labellum, spread widely.
The green "hood" is the dorsal sepal.
The protective "arms' are the petals.
Here is the flower seen from directly in front,
but seen from low down to look into the "column"
The "spur" is just visible, below the flower.
Here is a similar view taken today.
You can see the column which is so well protected by the dorsal sepal.

Finally, here is another shot, taken with natural light.
The flower is merely 5mm wide and deep.
The spur behind is probably about 1 cm long.
The Tangle-root Orchid has a delicious sweet perfume, but on a cold, windy day like today, it was barely noticeable. On a warm day, no doubt it would drive the insects crazy with desire.

My favourite image.

It shows the left hand flower as seen from the front.
The "Gravy-ladle shaped" labellum (wider than deep) is clearly visible.
On the right it shows the side view perfectly.
Note the closely hooded green dorsal sepal and side petals
and the long white and purple "spur" behind the labellum.


Junior Lepid said...

What an interesting plant! Well done, Denis.

I enjoyed learning about this species.

Thank you.

Denis Wilson said...

In your area, you don't have to worry about missing the Epiphytes, while looking for terrestrials.
Its odd how there are some consistencies in Orchid flowers, but their life-styles are so completely varied.
This one is an extreme. It is almost a class of its own, not a rock-lover, nor a tree-lover (nearly). It is almost always always "pendant" - like my example at top, where it is simply hanging from a thread.
It makes them similar in life-style to those "air plants" (Tillandsias) in the Bromeliad family. Totally unrelated, of course. But similar way of surviving.

Denis Wilson said...

As it was less windy today, I went back out and took a series of new photos.
Much clearer - the tiny little flowers wave round in the slightest breeze, let alone any wind.
I think they are much better.

Gaye from the Hunter said...

hello Denis,

you've got some excellent close-up pictures of the tiny flowers there, well done.

There is a big difference in the time span from my sighting of the Tangle Orchid in Barrington Tops National Park late January - interesting indeed.

I would love to get a trip in to Barrington soon for some orchid hunting, but I doubt it will happen. I may however, be able to manage to get the Hunter Region Botanic Gardens to search out ground orchids.


Denis Wilson said...

Hi Gaye
I noticed the time difference.
PlantNET says flowering time "Sept to Jan".
I would have expected more northerly areas to be earlier than this.
Its the first time I have seen it flower here, so I don't know if this is early here, or not.
Yesterday's photos were "ordinary" but I managed some better shots today.
From memory it is the first time I have gone back and actually removed images I was not happy with.
I feel happier. now.
My pride was tormenting me.

Gaye from the Hunter said...

Hello Denis,

when I saw Tangle Orchids flowering in the Barringtons late January, it was also the first time I had seen them flowering, so I also have nothing to compare then with.

But, as you know, the Williams River Day Use Area in the Barringtons is low altitude, and I expect you are at a much higher altitude. I too, would have thought the flowering times re north and south, and lower vs higher altitude to be opposite to what you have found.

It is most interesting to compare our findings in this way.


Denis Wilson said...

Hi Gaye
Now that I know where to find these plants easily (10 minutes down the road), I will check them closely in future.

Jenny K. Phillips said...

In 1996,I did a botainical painting of this little orchid I found in the atrium collection of the Esso Building, Southbank, Melbourne.
Is it endangered as I was led to believe?

Denis Wilson said...

Hi Jenny
It is not listed on the Federal EPBC Act as endangered, or vulnerable or threatened.
It is not noted as "threatened" on the NSW PlantNET site.
It may be listed in Victoria - I do not have that list linked on my computer.
It is highly localised (like many Orchids), and it ceertainly is not common around my area. I only know of a few localities where it occurs around here.
Were you happy with your botanical drawing?
In hte wild it is hard to [photograph, as it hangs down by hte roots, from small branches of shrubs. So any breeze makes the entire plant swing around. Doubtless you were able to control for that.
Thanks for dropping by.