Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Sunday, April 08, 2012

Bungonia and Long Point, and Badgery's Lookout

These three areas are closely located - but contain noticeably different habitats.

They all are overlooking the Upper Shoalhaven River.
Bungonia is (famously) located on a Limestone reef, which has eroded severely (such is the nature of Limestone). The surrounding geology is mostly sandstone (which has not eroded as much). But even my untrained eye can detect variations in the soil and stone colour and consistency as one moves from area to area within the Bungonia State Conservation Area. The famous gorge is between the "Lookdown" and the Bungonia Mine pit.
Long Point is next, and I must stress that I am not a geologist, so I will simply state that to my untutored eyes, the rocks there appear to be more shale-like. But it has higher moisture retention characteristics, seemingly, judging by the plant growth in the area.
Badgery's Lookout is the next accessible point along the Upper Shoalhaven River. It has a different geology too. I recognise that, mostly because of the different trees and specifically, by the different Orchids which grow there.
But here, at least I can quote from the experts who contributed to the Mulwaree Shire Community Heritage Study, 2002 - 2004
  • "The sandstone cliff of the marine Snapper Point Formation [a body of rock] is adjacent to the lookout, while further east, a cliff with three distinct levels can be seen, a lower sandstone cliff [Snapper Point Formation], a plateau in the middle [Wandrawandrian Siltstone] and an upper sandstone cliff [Nowra Sandstone]. A peneplained surface [a nearly featureless, gently undulating land surface of considerable area] is broken by large rock formations [phyllites and graptolitic shales] which form the base of the sedimentary sequence described above. The headland itself is capped with basalt [a volcanic rock] and petrified ancient soil."
In the most simplistic terms, although these three lookout points are all similarly high over the Shoalhaven River, and give superficially similar views of the River Gorge, and are little more than 6 kilometres apart (directly) in fact they reveal the immensely complicated geology of the entire region.

At Long Point Lookout there is an old stone toilet block hidden away, nearly out of sight in a patch of dense trees and shrubbery. Around that area one finds masses of leaves of Acianthus and Chiloglottis.
As often happens with both those species, there are relatively few flowers to be seen.

Acianthus exsertus
Chiloglottis seminuda
 On the Lookout edge of Long Point, we found this nearly finished flower of a Diplodium. From the extremely fine tip of the "galea" (hood) and the position of the points, I believe this is likely to be Diplodium revolutum which we had found an hour before on the dry rocky track at Bungonia.
Possibly Diplodium revolutum
Sinus and Labellum of that possible Diplodium revolutum
This plant of Diplodium obtusum was the only flower of this species which we found at Long Point. We had seen many of these plants on a previous visit there, on February 24 It is interesting to see the same species still flowering in the same group of plants, some six weeks later.
Diplodium obtusum

 At Badgery's Lookout, we found Diplodium reflexum
Rear view of Diplodium reflexum

Front-on view of Diplodium reflexum
its hows a much blunter tip than the
related Diplodium revolutum.
And what is this?
This plant is obviously a Pterostylis Greenhood,
It has no stem leaves, nor did it have basal rosettes.
Also the plant appeared to have been nibbled by something.
But what? The area is so dry and stony 
it is hardly likely to be snail damage.
And Wallabies and Wombats normally chew off the entire flower.
The points, the tip of the hood and even the labellum
had all been "shaved back".
Thus nearly all the diagnostic characteristics had disappeared.
We end with a puzzle.
Is it Pterostylis curta?
That seems unlikely given the dry location
and the lack of basal rosette of leaves.


Flabmeister said...


I note that you exclude the Easter Bunny from your list of potential Greenhood munchers. Have they been eradicated from the area?


Denis Wilson said...

Silly me!
Of course it must have been the Easter Bunny.
Certainly scats indicate large numbers in Bungonia. Not sure about the other locations, but they are likely to be there, because there are farms not far from both the other lookouts.