It has taken us many years to find the right property for our next adventure, and one of the keys things we looked for every time was warrens … wombat and rabbit warrens.
Most people think that these animals are pests … yes and no. They are destructive to crops if you don’t protect your crops correctly, but they can tell you an amazing amount about your soil without having to do any serious soil testing up front. Here is an example wombat hole.
This hole clearly gives a snapshot of the soil profile in this area of scrub. The top 20 cm of soil, is a dark brown sandy topsoil. This is known as sandy loam. It is very easy to work with and provides for excellent drainage.
The next layer is a yellowish sandy substrate for about 60 cm. This substrate was laid down in this region around 20,000 years ago. Doing a little geological research, it was most likely blown onto the slopes when the lower area was infact an inland lake during the last ice age. This sandy substrate allows for easy drainage and will ensure that the soil is not water logged.
Finally, at the bottom of the wombat hole, there is evidence of pebbles of a gravel-like consistency. This gravel has a brownish-red colouration, indicative of high iron. There are also obvious chunks of quartz-like rock with inclusions of granite an glassy sandstone. This indicates that this level of the soil profile is close to bedrock, probably volcanic in nature as the quartz with inclusions can only occur at high temperature.
So, what does this tell us? This region can be used for shallow rooted trees, as evidenced by the dwarfed eucalyptus on the slopes behind. You can also put a structure here quite easily by cutting out and creating a solid packed base or by dropping piers directly to the bedrock. You can also improve the top soil using bio char before adding compost to make a very fertile garden bed for veggies. All this info from a simple wombat hole!