Sunday, 30 March 2008

A sleeping elephant

When you grow up in an area you tend to ignore the features in the landscape. That's certainly true for me. I grew up on the Victorian Volcanic Plains, an area of lava flows covering 23 000 sq. kms. Many of the 400+ volcanoes that erupted over millions of years stand above the plain, looking spectacular, but we get so used to seeing them that we don't 'see' them.

The plains are flat - well, perhaps if you were riding a bicycle you'd disagree - so the low volcanoes can be seen from a great distance and were navigational points for the early settlers.

Mount Elephant is a stand-out scoria cone, 240 metres high with a crater 90 metres deep, and well known because it's on a highway. It used to be privately owned but the local community purchased it in 2000 and are replanting with indigenous grasses and herbs. Several years ago they organised a successful 'Music on the Mount' event, using the crater as a natural amphitheatre.

The second picture below was taken into the sun so looks very washed out, but it does show why it's called Mount Elephant. The lake in the foreground is Lake Gnarpurt, dry of course because most of our lakes are dry.

Mt Elephant

Mt Elephant

Saturday, 29 March 2008

Running the gauntlet

The laneway becomes a race track when the extended family visit the farm. There are rules imposed on the juveniles. They are not allowed to ride the motor bikes, go carts, bicycles or old 4-wheel drive on the farm itself, so they have a circuit around the house and sheds and down the lane to the front gate. One-way traffic only. It is very noisy and dusty, except in the mornings (when the young sleep in) and at meal times of course.

But still we see the Superb Fairy-wrens, White-browed Scrubwrens, Yellow-rumped Thornbills, Common Bronzewings, Galahs, Gang-gangs and Willie Wagtails. And last week a Restless Flycatcher stayed with us all week.

So it was something of a surprise to find a very large Gum Moth caterpillar crossing the laneway and surviving the trek. (Why did the moth cross the road? To get to the other side.) It's an impressively large caterpillar, bright green with coloured spots. There is a faintly-dark line along its back that is the heart - unfortunately I didn't have my microscope with me to check out the pulsations. The breathing-holes on the sides can be clearly seen. We thought this caterpillar was the common Emperor Gum Moth Ododiphthera eucalypti but actually it's the less common close relative, the Helena Gum Moth (although it's also called an Emporer) Ododiphthera helena. It has a pale pink lateral stripe, red spiracular openings (the breathing holes), short white bristles and small paired spikes on the thorax and the eighth abdominal segment. This particular caterpillar is in its final instar (growth stage) - earlier instars have different coloration and patterns.

It feeds in broad daylight on gum trees and will spin its silk cocoon (they are in the same family as the silkworm) in late autumn. The large moth will appear in spring.

The caterpillar was left next to the track. I wonder if it survived the Laneway Grand Prix.

Reference: http://linus.socs.uts.edu.au/~don/larvae/faqs/

Friday, 28 March 2008

Surprise, surprise

In 1836 the explorer Major Thomas Mitchell climbed Mt Napier and saw a little hill to the south that he named Mt Eeles. Major Eeles and Mitchell were veterans of the Peninsula War. The name stood until 1855 and then a Surveyor General's map showed it as Mt Eccles, a typographical error that has stayed with us ever since.

Mt Eccles is only a little bump on the horizon. In the photo below it is the hill on the right.

In fact, it is a volcano, and there is a lake in the crater called Lake Surprise. It is a suprise too, because you can't see the lake until you are standing on the rim of the crater. It's normally about a kilometre long and 30 metres deep and you can walk down into the crater and 'do a loop' on a well-maintained track. The mountain is now a National Park, a very popular picnic and camping spot. The information centre is pretty good too. The photo below, taken from the summit, is from a booklet called Volcanoes in Victoria. It must have been taken a while ago because the lake doesn't look like that now. I was there last week and the water level has dropped considerably, as you can see in the third photo. Presumably the drought/climate change is having an effect there as well.

Lake Surprise, Mt Eccles

Lake Surprise, Mt Eccles

Wall to wall fencing

There are lots of stones on the Victorian Volcanic Plain. Lots and lots of stones. The plain is dotted with inactive volcanoes, and the evidence in the form of ash, tuff, scoria and stone is everywhere. It has dictated the type of farming, the type of vegetation and the type of fencing.

The area was first settled in the 1830s and by the end of the 1800s miles of dry stone fences had been constructed using the basalt rocks immediately to hand. Of course there were stonewallers and there were skilled stonewallers, illustrated by the two photos below.

The first is at a tourist stop at Derrinallum, with an explanatory board. It's a beautiful wall, with a double row of copestones on the top and larger throughstones placed at regular intervals. A real craftsman built this wall. The second is at Lake Condah, now part of Mt Eccles National Park. It's a very haphazard affair but I'm guessing a lot of hard work was involved nevertheless.

There has been a book written about the walls on the plains. It's called If These Walls Could Talk and I'm going to have to track down a copy in my library.

I'd also be very interested in knowing if anyone has researched the use of the walls by lizards and snakes, because their natural habitat is fast disappearing into stone crushers.

Symmetry in nature (2)

What do you think this is?


It's another perfect example of symmetry in nature. A friend has a passion for cactus plants and this is one of them. His cactus flower photographs are beautiful, but I found the patterns of the spiky bits fascinating.

Thursday, 27 March 2008

A secret message?

There are two Silver Banksias Banksia marginata growing in my garden, and they've been coming up to full flower the last couple of weeks. (Banksias take a while to come to the point.)

And last week I was holidaying 300 km away, and in my favourite bit of heath the Silver Banksias are coming up to full flower. How do they do it? What triggers the mass flowering? And why do they flower now, when very little else in the bush is flowering?

I'm not complaining. The sight of numerous shrubs covered in yellow spikes is a joy that I look forward to every year.

Wednesday, 26 March 2008

Approaching storm


This one's for Adam. He knows why.

I'm pretending I'm not here

When I first saw the Echidna it was out in the open, snuffling along, eating ants. As soon as it heard me approaching it headed for the long grass nearby and squatted. If I hadn't seen it move into the grass I would never had picked it out because the light tips to the spines on its dark back are perfectly coloured to blend in, especially in summer.

I moved up close and decided to wait it out, thinking I'd get a better photo when it moved out into the open again. The short beak occasionally came up to sniff the air. If I made the slightest noise the shoulders hunched, causing the spines to sit more upright.

In the end I gave up. It had more patience than I have. When I came back past the spot half an hour later it had gone. They have a very large territory (possibly 60 hectares) so I wasn't about to go looking.

Tuesday, 18 March 2008

Clouds









A lot lot cooler today but I can smell and see smoke. We Aussies are on edge whenever we smell smoke! I've been photographing clouds. Here are some I've seen over the last few weeks.

Sunday, 16 March 2008

I can see you

Katydid

I found a creature, with long thin antennae and straight wings that look remarkably leaf-like, hiding amongst the leaves of a shrub in my garden. It's a katydid.

I believe the male produces sounds by rubbing the wings together, and other katydids can hear the sounds with an ear (tympanum) on each front leg just below the knee. Human ears are funny looking things really, but can you imagine if they'd ended up on our knees instead of our heads?

Saturday, 15 March 2008

Ruby

This isn't the Old Man Saltbush I wrote about earlier this week. It's a Ruby Saltbush, a common plant in the drier parts of Victoria.

Ruby Saltbush


Ruby Saltbush

When we called in to have a look at the dry lakebed of Lake Meran it was about midday, the temperature was about 39, even though it's autumn, and the heat reflected off the sandy soil around the lake so we didn't hang around. The coolness of the air con in the car was very attractive.

But the Ruby Saltbush Enchylaena tomentosa var. tomentosa looked quite comfortable in the heat and arid environment. The brightly coloured 'berries' and succulent leaves are edible, and were an important antiscorbutic vegetable for some early explorers of Australia. (I had to look up 'antiscorbutic' - it means they ate it to guard against scurvy.)

I wonder why the birds haven't eaten the berries.

Thursday, 13 March 2008

The lakes have disappeared

The lakes in north-central Victoria attract a lot of families in the summer, including ours - water-skiing, windsurfing, swimming, jetboating and fishing. The levels are held artificially high because of the interconnected irrigation storage.

But not this year. There isn't enough water to go around.

Lake Boga, south of Swan Hill, is dry for the first time ever it seems. It's hard to imagine that it was used as a Catalina Base in WW2. The local residents, who have built their homes around the edge for the view, got a bit annoyed when the fish started dying. Thousands of fish, especially the introduced European Carp. It got a bit smelly at Lake Boga.

Lake Boga

And Lake Meran, west of Kerang, has been dry for several seasons. The River Red Gum seedlings are encroaching inwards from the bank and the diving platform is left high and dry. No church picnics at Meran for a while!

Lake Meran

Lake Meran

Before European settlement the lakes in this area used to flood and dry out regularly - most of them have stumps of trees in the middle. It's hard to believe that with climate change we'll ever see the lakes full again.

Wednesday, 12 March 2008

Symmetry in nature



Passionfruit tendrils.

Old Man Saltbush

Several years ago we drove through outback New South Wales. How anyone could think the outback dreary beats me. The variety of geography and plant life is amazing. In one area south of Hay it's very flat and saltbush is about the only thing that grows there. I couldn't go past the black cows against the grey-blue saltbush without photographing them.

Last weekend we visited a cousin at Drummartin north of Bendigo. He has planted saltbush in the house paddock as a trial alternative stock food. Saltbush is quite edible and nutritious, just a little salty. He lops the top of the shrubs occasionally so that the available leaves are at sheep level. He's also planted a couple to shade the dog kennels. I have also planted one in my garden - we're on water restrictions so a plant that can survive the toughest of droughts might be all that survives here. Mine is the Old Man Saltbush Atriplex mummularia. I'm not sure which saltbush is growing on the farm.





Tuesday, 11 March 2008

Sheep heading for the dam

Sheep in a paddock at Kamarooka, stirring up the dust as they head to a dam for a drink on a hot day.

Kamarooka


...roads ribbed with tree shadows run away from me towards a horizon of gums.

I wish I'd written that, but no, the credit goes to Graeme Kinross-Smith in Long Afternoon of the World. It's a novel, beautifully written, and set in my part of the world. This photo was taken last weekend at Kamarooka, wheat country north of Bendigo, on a stinking hot day.

Wednesday, 5 March 2008

Dog Rocks

Several of us met the Green Corps team at Batesford this morning, and went for a walk with them through a wonderful, privately owned, bush block on the Moorabool River. The Green Corps has been weeding prior to a walking track being put in place by the City of Greater Geelong–one day we'll be able to walk from Batesford to Fyansford where the Moorabool joins the Barwon River, and then follow the river on to ocean at Barwon Heads. We can dream, but there are plans in place and the path already exists in places.

We were at Batesford to encourage the young Green Team members to observe and record the birds they see as they work. We saw Dusky Woodswallows, Wedge-tailed Eagles, Spiny-cheeked Honeyeaters, Red-browed Firetails, Rufous Whistlers and lots of lorikeets. There were a lots of birds flying between the big old Yellow Gums and Red Gums and the understorey of small shrubs.

This particular bush is in an area called Dog Rocks, a very interesting area geologically speaking. The Dog Rocks are Late Devonian granite (about 350 million years old), formed below the surface in the molten state and then uplifted and exposed. Greenstone (epidiorite) is also a component of these outcrops. It's a very hard, dense, dark-greenish rock and was an important source of axe-head stone for the Aborigines in this area and to trade beyond. And it's because of these rocks that Geelong has a huge portland cement industry. But that's another story.

The first two photos were taken in winter on a neighbouring property which is grazed by sheep, the other two I took this morning from the road. As you can see, it's very very dry here.



Most of the rocks are on private property so it was good to have a chance to get up close and personal.

Monday, 3 March 2008

Order! Order!

More on the naming and arranging of all things natural- taxonomy.

Isaac Asimov wrote 'The card-player begins by arranging his hand for maximum sense. Scientists do the same with the facts they gather.' And Stephen Jay Gould said 'Classifications both reflect and direct our thinking. The way we order represents the way we think. Historical changes in classification are fossilized indicators of conceptual revolutions.' (I googled but can't find the source for either statement but both are quoted in Botany by Moore, Clark and Vodopich.)

PS. Message to Snail. Yours was the featured blog when I opened up the Nature Blog Network page this morning.

Sunday, 2 March 2008

John Ray? Who's he?

You will have all heard of Linneaus. But have you heard of John Ray?

I've just finished reading The Naming of Names: the search for order in the world of plants by Anna Pavord. (I mentioned it in a blog several weeks ago. Oops, maybe that means the book is overdue at the library!)

I expected that Linneaus would get a lot of Anna's attention, but no. He gets a mention or two in the last chapter, but John Ray is given a huge pat on the back. I knew that he is called 'the father of botany' but didn't realise that he himself coined the term in 1696, that he worked out six rules of classification that are still used today. He divided plants into dicotyledons and monocotyledons, grouped plants on the basis of multiple similarities, rather than just on a few key features (such as number of petals, medicinal purpose, size, leaf shape) that his contemporaries and earlier men had been trying to do. Ray suggested that plant names should be changed as little as possible, that related plants should not be separated. And he was the son of a blacksmith!

Naturally there is a spanner in the works. Ray didn't know about DNA. Scientists can now work out the evolutionary tree, so there has been, and will be, some major shifts happening. Some very unexpected relationships are turning up, and not only in the plant world. But that's OK. We amateurs can live with that. Eventually field guides will be published that incorporate the changes and we just accept it (with a whinge or two) and move on.

But I notice in my latest Growing Australian magazine that it is proposed that the dryandras be moved into the banksia genus, and callistemon be included within the melaleucas. So Dryandra pulchella becomes Banksia bella. And so on. Oh dear.

Saturday, 1 March 2008

A prickly customer

It can be a bit of a pain to walk through the bush when the undergrowth is thick. Even more so when there is Bursaria Bursaria spinosa present.
This shrub has thorns, hence the species name, spinosa. But the genus name Bursaria comes from the shape of the seed capsules - they're shaped like little purses and quite beautiful at each stage of their development.
Bursaria is also called Sweet Bursaria, because of the fragrent flowers that appear in spring and summer. It's a very common plant, but as is often the case, its beauty can often be overlooked because it is common. But it is interesting that scientists have found that the Bursaria has a relationship butterflies and ants - certain species of butterflies feed on the plant, the larvae graze on the plant and a certain ant species protects the caterpillar from predation and hosts the pupae within their nest. The Eltham Copper Butterfly is one of those. This is what the Department of Sustainability and Environmant (DSE) has to say on their webpage:
The Eltham Copper Butterfly prefers woodland habitat with an understorey containing the shrub Sweet Bursaria and a ground layer of native grasses, mosses and leaf litter. Female adults lay eggs during summer on the shoots and stems of Sweet Bursaria (Bursaria spinosa), and sometimes in the leaf litter close to the base of the plants. The larvae hatch after about 10 to 14 days and shelter and develop in the ant's nest located around the plant roots. Larvae are nocturnal, sheltering in the nest during the day and emerging at night to feed on the Bursaria leaves, where they are constantly attended by the ants. In return for this protection and care, the ants feed on secretions of sugar and amino acids from the larvae. This may keep the larvae free from fungal and bacterial disease. Adult butterflies emerge between late November and January. They feed on the nectar produced by the flowers of small and larger Sweet Bursaria plants, and sometimes on nectar of other plants such as Hakea and Cassinia species.

Bursaria spinosa

Bursaria spinosa flowers

Bursaria spinosa seed capsules

Bursaria spinosa seed capsules

Red and yellow and...

The view from my back door, enhanced by a rainbow. I'm in the middle of suburbia, but the trees make it livable.

A shelly beach

My family met at Point Cook today for lunch because it was my step-mother's 19th birthday yesterday. No, my dad hasn't lost his marbles or succumbed to the charms of a teenager. She is actually 76 but was born on February 29. And hopes to celebrate her 21st in eight years time.

Now, I have to admit that, although Point Cook is not very far from home, I have driven past many times and never been there. I was pleasantly surprised. That's Melbourne on the horizon, just across Port Phillip Bay.

And on the sandy shore there were piles and piles of sea shells. My ignorance of all things marine is total, but I am curious to know why there are so many shells in this spot. Have a look at a map - Port Phillip Bay is huge, but it has a very narrow opening to the ocean. Does the shell debris come from the bay itself or does it get washed in all of the 50 kms from the ocean?

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