Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Wednesday, February 20, 2008

Greenhoods - late summer brings "promise".

The local Greenhood Orchids are starting to flower. Well, I should say that the late summer and autumn-flowering varieties are starting to flower.
The first Greenhood which I found in flower this new season is Diplodium pulchellum, the so-called "Escarpment Greenhood". This particular plant was budding in late January, and was open on 31/1/2008. Others are still developing in another location, not far away. This specimen is not growing in the typical habitat for this species, adjacent to or underneath a waterfall (i.e., within range of the spray drift from a waterfall). This one was growing in a muddy creekbed, alongside some of the Chiloglottis sylvestris plants about which I wrote recently. In this photo above, you can just make out the "labellum" of the flower - held inside the hood. The labellum of Greenhoods is a sensitive organ, and it moves forward or backward in response to movement, or typically, the presence of an insect. This is part of the pollination process of these flowers. When they sense an insect is inside the flower, the labellum snaps back against the column (within the hood) to try and trap an insect where it will brush against the "pollinia". In the case of this particular flower, although I saw it on 3 separate days, I never saw it with its labellum "set" in the forward position.

Close-up of the labellum,
showing its "notched" appearance.

This plant was difficult to photograph because of its location in a Melaleuca thicket (you will have noticed that I was using a flash on all shots, because it is so dark in this area). When you consider that there is a little creek flowing through where these plants are growing, the reality is that one has to get "down and dirty" to take these photos. Oh, and did I mention the Leeches? DJW 1: Leeches 0 on this occasion. I saw the little blood-sucker coming!

In fact this flower was knocked over when the creek level rose, after heavy rain. You could describe it as a mini-victim of a mini-flood.Still, this plant is slightly better off than the Chiloglottis plants nearby which were actually underwater for about 3 days. But then again, all these occurrences are natural, and so presumably these plants (both species) have adapted to these conditions, for they flower in February, in Robertson, which is our normal summer rainy season. So they must expect the occasional inundation.

I shall write more over the next few days about other Greenhood species which are just coming into flower now.

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