Focus on Forest Soils
Posted on 1 March, 2013 by Connecting Country
The Goldfields of central Victoria have a reputation when it comes to soil – a reputation for not having any. And if you’ve ever planted out your garden with a ‘Castlemaine Shovel’ (otherwise known as a crow bar), then you’ll know it is often a well-deserved one. But, as participants in Connecting Country’s ‘Forest Soils’ workshop found out recently, a range of soils do still occur throughout the shire – albeit with less depth and fertility than would have occurred prior to the gold rush era.
The workshop was held over two consecutive Sundays in February. On the first weekend, Dr Lesley Hodgson from Latrobe University introduced participants to the geology of our region and the process by which soils are created over long periods of time. She also taught participants how to undertake field measurements of the texture, pH and colour of soil at different depths. Participants examined soil from an area of sedimentary country above Moonlight Flat and also from an area of granite-derived soils at near Faraday. The soils were found to be quite different in texture, and were surprisingly acidic at both locations.
The second day of the workshop initially investigated the relationship between soils and vegetation. Following a ridgeline near Glenluce, local ecologist Damien Cook led participants from the dry, shallow soils at the top of a hill down to the much deeper soils along the creek. Damien pointed out how the composition of plant species changed as the soil changed; short, spindly trees and lots of shrubs at the top to the hill and large straight trees with a grassy understorey occurring down the bottom. The type of soil, depth of soil, and associated availability of water were the most important factors driving which plants grew where in the forest.
Local resident Doug Ralph then lead us on a meandering walk along Fryers Creek (near Irishtown) and showed us a diverse array of sites which clearly illustrated the effects that gold mining and gravel extraction have had on our soil. Dreading and sluicing in the early 20th Century has left deep erosion gullies, and in many places the topsoil was completely removed or washed away – right down to the bedrock. On a brighter note, Doug also told us how he has witnessed the natural regeneration of much of this landscape since he was a boy. Large areas that were once completely devoid of vegetation are now covered in Wirilda and other acacias that have regenerated from the soil seed bank; fertile topsoils are being created again.
The forest soil workshop was part of Connecting Country’s 2013 Education Program. Upcoming events in the program include a free evening talk on ‘environmental weeds’ on the 13th March (by Geoff Carr and Ian Grenda) and a talk on designing wildlife corridors in Elphinstone on 10th April (by Dr Rodney van der Ree and representatives from the Superb Parrot Project). See the Education Program 2013 on the Connecting Country website for more details.
Participants in Day 1 of the forest soils workshop examine a soil profile near Faraday – heads down!
Doug guided us to this pebbly ridge near Irishtown which was once an ancient river bed. Much of it has been removed by mining activity.
A suggestion, please add a “print” button to the website, so that I can print off the article above without all the unnecessary appendages.
Regards,
Neil Webster.
A great idea Neil. I’ll look into it straight away.
Thanks for the feedback,
Chris