Friends of the Box-Ironbark Forests

The curious circular earth formation pictured below isn’t a mysterious religious site. It’s a puddling wheel, and if you want to know how it used to work, check out historian Marjorie Theobald’s article ‘Commissioner Bull and the Puddling Machines: Castlemaine’s first Environmental Cause’:

Puddling machine, Cobblers Gully: Circular ditches like this, with islands in the middle, are fairly common in our district. The fallen trees are recent intrusions--natural heritage at work.

‘In the years 1851-1855 the area known as the Mount Alexander gold fields, about ten square miles including the towns of Castlemaine, Chewton and Fryerstown, was ransacked by the alluvial miners; no creek was left unchanged, no gully was left unscarred, no ridge was left unpierced. Concern for the environment as we understand it today did not exist. It comes as a surprise then to find that in January 1855 Resident Gold Commissioner for Castlemaine, J.E.N. Bull, took a stand on precisely these grounds: he sent to each proprietor of a puddling machine an edict that from the 31 March 1855 these machines would be banned from the main creeks in his district. This was necessary, he wrote, to safeguard the water supply of Castlemaine, the operations of the miners using cradles and Long Toms, and the health of the creeks and flats generally.’

What happened next? To find out, check Marjorie’s excellent article on the online Central Victorian Ecology blog.

About 100 people turned up to the first public consultation meeting on flood management on February 18 at the Castlemaine Town Hall.

The meeting consisted of three presentations on flood issues by Catchment Managers and water industry experts—unfortunately rather repetitive and sometimes barely audible in the town hall acoustic. The presentations were followed by one on one discussions between officials and residents using large maps of the area.

Forest Creek/Barkers Creek junction, January 2011: at the high point of the floods water coming into the streams was five times the carrying capacity of the stream beds.

There was an expectation that this would be a fiery meeting because of dissatisfaction with the way flooding has been handled: and it was clear from this meeting that there’s still plenty of anger and pain in the community about the issue, some of those affected by floodwaters  calling for extensive clearing of vegetation along Barkers and Campbells Creeks. It’s also clear that there’s a bit of confusion in the community about who exactly is responsible for our waterways, and it’s to be hoped this can be cleared up in this process.

The main thrust of the meeting, however, was to take and assess as many ideas as possible to prevent a repeat of the damage inflicted by the floods of 2011 and 2012. Among the ideas fielded were:

• Essential services protection: the Castlemaine water treatment plant being a prime example. Flooding of this plant caused significant downstream pollution and some potentially serious health issues.
• Vegetation along creeks: there are still calls for wholesale clearance, on the assumption that ‘the flood wouldn’t have damaged houses if all those trees hadn’t been there.’ This belief is quite false [see our posts here and here]. One group in 2011 even called for the clearing of ‘all trees growing below that which would be considered the high water mark.’ This would involve demolishing about a quarter of the Botanical gardens and turning the creek system into a gigantic ditch. Nevertheless it’s clear that some management of vegetation [particularly of willows, which raise the stream bed] is justified.

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The ant pictured below is a member of the genus Rhytidoponera. The curious thing about it is that the creature is labouring to carry a shoot of moss [Pseudocrossidium crinitum].

Ant behaving strangely, Kalimna Park, February 2013

As far as we know, ants feed on other invertebrates and forage for such matter as honey. Moss somehow doesn’t fit the bill. The specimen above lugged its burden over difficult terrain for about a metre, then abandoned it. Any clues about this behaviour are welcome.

The photo below could be duplicated hundreds of times through our region: a tree sitting on a ‘pedestal’on the edge of a deeply eroded gully. When that tree was young, it was at ground level. So, where has all the soil gone?

Tree 'pedestal', German Gully: once this tree stood at ground level. Annual soil loss in most of Australia is estimated at one tonne per hectare, twice the rate at which it can be replaced by organic decomposition.

The obvious answer is, it’s been washed away downstream, eventually ending up in the Loddon, as a result first of nineteenth century mining works, and afterwards of a long process of erosion.  Here’s a report from the Mount Alexander Mail, August 27 1854:

‘The water in the Loddon was higher last week than it has been all the season. The puddling and sluicing on the banks of the stream have converted its once clear current into as muddy a state as many of its tributaries. It is said that the fish that were occasionally washed down Fryers Creek sunk to the bottom, as though suddenly deprived of motion, on reaching the earth-laden waters of the Loddon. Just now it is questionable whether any of the finny tribe can be found near the Junction.’

Almost all of our eroded gullies show a dual process: relentless erosion, and painfully slow build up of vegetation cover counteracting that erosion. In theory, land management policy encourages the second process to stop the first.

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