Soil Management
There is much to tell about how we manage the soil at Eaglerise Farm. Our view is that we farm the soil biological community. We farm all the living elements within the soil profile. Without managing the soil biology, we’ll have nothing. A successful, vibrant, regenerative ecosystem needs – air, water, nutrients, energy and friends. The soil ecosystem is no different. Our management is about providing these essential elements and encouraging ecological succession to develop a diversified biology that will provide for a diversified pasture in our production areas and will provide diversified biology within our natural ecosystem areas.
Our soils originate from the parent rock of gneiss. Gneiss is a metamorphic rock formed by subjecting schist, granite or volcanic rocks to intense temperature and pressure. It displays distinct banding. It could be compared to a metamorphic version of granite. Both contain feldspars of potassium and sodium, quartz, mica and smaller amounts of coloured minerals. The predominant difference is the coarser texture of gneiss with its ribbons of different minerals running through it, against the more evenly speckled granite.
The rocks at Eaglerise Farm have been dated to 630 million years. The surface rocks deteriorate and crumble when exposed to the weather. This breakdown emanates from the boundaries between the varying ribbons of minerals. We have used the crumbled material as road base to form the roads and tracks on the farm.
Eaglerise Farm soil was severely impacted by the rabbit plagues of the 1940s. Rabbits denuded the farm of vegetation and disturbed the surface with warrens. Subsequent rains eroded the already fragile, intrinsically low fertility, Australian topsoil and transported it down the slope to deposit it on our neighbour’s farm! This left even poorer soils that have only had 80 years or so to develop the capacity to grow a diverse range of agriculturally productive plants.
Our holistic management style leads us to look at the whole farm as an ecosystem with minimal inputs. This means that the soil is vital to provide diverse habitat for soil biology that forms the base of the ecosystem food web. This biology emanates from the micro plankton in the soil, the zooplankton and upwards through the predators in the soil, to the echidnas and other wildlife. Then the plants that grow from this complex system that feed our grazing animals. This follows the regenerative agriculture principle of understanding complex adaptive systems.
The three areas of soil interests are: soil chemistry; soil biology and soil physical attributes. All three can be improved by increasing the soil organic matter. The easiest way to achieve this is to grow your own organic matter! Many farmers are doing this through judicious grazing systems that maintain ground cover and support perennial pasture composition.
Soil carbon provides the energy for the soil biology to grow and multiply. This increases the opportunity for the soil biology to free up soil nutrients. Increasing soil organic matter also helps bind the soil particles together to form stable peds and increase water infiltration and then increase soil biology.
It is often stated that, “It all starts in the soil!” My next question is, “Where does it go from there?” Agroecology leads us to respond by investigating the whole farm ecosystem.
I previously thought that I was a soil-biology farmer, that I farmed all the little bugs and micro-organisms in the soil. However, agroecology leads me to be an ecological niche manager. I am an apex predator in our ecosystem, it is my responsibility to manage the ecological niches within our wider farm ecosystem. This is important within the soil ecosystem. To be effective at this we need to appreciate the level of complexity within the soil profile. We need to understand the pattern rather than the detail. This follows the permaculture principle of designing from patterns to detail. This principle can be adopted for ecosystem design and management. If you can observe and understand the pattern, often, the detail will work itself out. Your ability to understand the detail will increase as you understand the pattern that directs it.
We understand that “we can only do so much.” The concept of valuing and understanding the pattern and having the faith that the detail will radiate from the subsequent management decisions, allows us the opportunity to keep moving with our design implementation. This is where we follow a parallel path to Mark Shepard and his “STUN” management style. We propose his “Strategic Total Utter Neglect” as an appropriate description of our management style.
Paying for soil tests and then paying for the soil amendments recommended, and then paying for their application is, currently, beyond our capacity. This includes the extensive time investment. Other important factors include the energy required for excavation, transport and application; and the ecological damage in the extraction of amendments. Do we have the right to dig up someone else’s backyard so we can make more money?
This may sound quite heretical to some readers. However, in the light of our Eaglerise Farm philosophies, it is quite sound reasoning. We value the ecosystem outcomes over the economic outcomes. Our economic viability is currently supported by some fulltime employment. We appreciate the benefits this provides. We can then indulge our passion in developing a complex farm ecosystem with increasing diversity of habitat, niches and organisms. To revisit permaculture principles, we apply small and slow solutions. We are budgeting our resources to slowly improve our soils to allow them to then repay that ecological capital and maintain Eaglerise Farm for future generations.
What do I look for as a sign of healthy soil?
By this I look at visible signs. It is rather simple – no biology, no growth! As in all ecosystems, you need to identify ecosystem indicators. In the soil, it is the soil biology. The greatest visible indicator is the presence of earthworms. These marvelous animals indicate the level of chemical residue, the level of organic material, the presence of micro-organisms, the moisture holding capacity of the soil, the quality of the soil structure and the capacity of the soil to continue to develop to be ecologically and economically productive!
Your ultimate view of what makes a healthy soil depends on your overarching goals – make money or create healthy ecosystem. Often these can be inversely related. In some ways it is like the chicken and the egg – which came first. We have taken the road of managing the whole farm ecosystem, not just the soil ecosystem, to enable the economics to flow later.
Another of our ecosystem indicators are our wedgetail eagles. Higher order ecosystem elements are indicators of ecosystem health. We strive for healthy and complex predator/prey relationships that start at the bottom of the food web in the soil.
Healthy livestock and wild stock; healthy plants; complex symbiotic relationship between the plants and the soil biology. These are all sought out as indicators of a healthy soil system
It is well understood that nutrient dense food provides a more robust diet for everyone. We use Brix measurements as a nutrient density indicator. This gives us a measurement and record of dissolved nutrients in the plants. Therefore, it indicates the nutrient availability within the soil. This is also indicated by having healthy customers at the markets from consuming Eaglerise Farm produce.
Masanobu Fukuoka strives for a complex soil biological community. We strive to achieve this by developing a diversified pasture mix that provides diverse roots and soil habitat and adds to the soil energy cycle. An indicator of this is seeing the soil biosphere around the roots of plants when pulled up.
The permaculture principle of small and slow solutions directs us to slowly increase Carbon. We do this through managing our grazing style, pasture composition, assessing our ability to grow specific vegetables and therefore increase water holding capability, soil biology and nutrient availability. This provides an increasingly robust solution rather than tipping a recipe out of a bag. As per Elaine Ingham teachings, nutrients are locked up and unavailable – we need biology to release them. This takes time!
The tests that we find quite informative and economical are included in the Northern Rivers Soil Health Card, (NRSHC). This is a soil health assessment devised by a group of farmers in the northern rivers area of New South Wales. It only requires basic skills and resources but provides some extensive and quick results.
The NRSHC Tests include: Structure, Infiltration, Soil biology, Penetrometer, pH
I like to include a Brix measurement for a sample of the vegetation too.
This is an on-farm view of our soil map. We have two major plant communities and these indicate the soil where they grow. Our south-eastern slopes have tumbledown gum with some casuarina. The soil there is light coloured, very sparse with much exposed rock. The south-western slopes, however, have a white box and red string-bark community. The soils there are darker, much better and deeper. They hold grass much longer into the hot-dry season.
Coming down the slopes we have our drainage line soil. This has been highly eroded in the past and has much exposed rock. We have fenced these lines to exclude livestock grazing.
Our flatter slopes are more productive, having been able to retained more top soil during the rabbit plague. They tend to be dark grey sandy loams. The main community there is mainly red grass.
Our most productive soils are our slope soils. Here we have designed grazing paddocks with swales to increase soil moisture. We also have our fruit growing and production horticulture enterprise here.
Australian Soil Resource Information System is part of the Australian CSIRO organization. I have inserted their definitions here for you to understand the bigger, national picture.
RUDOSOLS: Minimal soil development
- Widespread but most have few commercial land uses because of their properties or occurrence in arid regions, or both.
- The largest areas occur in the desert regions of arid central and northwest Australia and support grazing of native pastures.
- In contrast, fertile variants formed in alluvium are used for cropping and improved pastures. Some dune soils of the Riverine Plain in the Murray-Darling Basin are irrigated for citrus and vines.
- Some Rudosol areas have spectacular scenery (e.g. Katherine Gorge and Bungle Bungle Mountains).
TENOSOLS: Weakly developed soils
- Widespread in the eastern half of the continent where vast areas occur as red and yellow sandplains.
- Large areas in Western Australia have red loamy soils with red-brown hardpan at shallow depths.
- Due to their poor water retention, almost universal low fertility and occurrence in regions of low and erratic rainfall, Tenosols are mainly used for the grazing of native pastures.
- In the better-watered areas landform prevents cultivation, but limited areas support forestry (east coast and southwest Western Australia).
DERMOSOLS: Structured soils
- Moderately deep and well-drained soils of wetter areas in eastern Australia.
- May be strongly acid in the high rainfall areas or highly alkaline if they contain calcium carbonate.
- Occur in the mountainous high rainfall zones of south-eastern Australia.
- Support a wide range of land uses including cattle and sheep grazing of native pastures, forestry and sugarcane. Cereal crops, especially wheat, are commonly grown on the more fertile Dermosols.
SODOSOLS: Soils high in sodium and an abrupt increase in clay
- Abrupt clay increase down the profile and high sodium content, which may lead to soil dispersion and instability.
- Seasonally perched water tables are common and subsoil horizons have a striking prismatic or columnar appearance.
- Usually associated with a dry climate and widely distributed in the eastern half of Australia and western portion of Western Australia.
- Common land uses include grazing of native or improved pastures for both dryland and irrigated agriculture, and forestry.
- Many will hardset when dry and are prone to crust formation.
- Dispersive subsoils makes them particularly prone to tunnel and gully erosion. Arid zone Sodosols may be strongly saline
You can now see the relative similarities of the national soil map, the on-farm soil map and our current paddock layout map. It was an interesting experience to see how our ecological perspective and our permaculture inspired layout has corresponded with the official landcape interpretation. I had to freehand the soil classification map from the ASRIS web site with no landscape features, so, there is a degree of error there. However, the patterns of land use are very similar.
The national classification gives very broard definitions that can be confusing when you are confronted with detailed soils under your feet.
Our rudosols and tenosols are our more productive soils. They are relatively shallow and overlay a deep granite layer. This creates well drained soils often until the profile fills when the soil above the granit can become waterlogged. In the deeper soils we have planted our vineyard. The grapes’ roots will penetrate and follow the soil moisture down deep.
The Eaglerise Farm dermosols present as both deep and shallow. They certainly have a low pH and are also free draining. When we have a storm event during the hot/dry season, our spring will recommence flowing in a couple of days and continue until the soil moisture in the upper hills has been drained.
The sodosols present similarly to the ASRIS definition. We see a perched water table eminating as a spring above our dam. When we dug the dam we found a source of grey, leached clay.
WOW dung beetles!!! They have a massive impact on our soil. Here you can see what has happened at Eaglerise Farm. The dung beetles have introduced water, nutrients, air and increased organic matter to depth as they have brought up the coarse gravelly sand in our poor soil areas and displaced it with cow dung. This is a big bonus of including cattle into our production system. We don’t get the same level of response from our sheep dung. The volume is not there to get down deep into the soil profile. We expect a quick response from the soil biology and that will move through to improved pasture for our Dorper sheep, Dexter cattle and pastured chickens. Down the track though, we’ll need to be careful with the impact the chickens will have on the dung beetle population here. We do not want to convert our dung beetles into eggs. They are too important. The dung beetles will need to do their work before the chickens get to the paddock.
What is the main thing that can be done right away to make soil healthy again?
Increase Organic Matter.
Most soil strategies are variances on increasing Organic Matter. Increasing biodiversity and complexity achieve the same thing really!
From a whole farm perspective, I also like to provide on-farm areas of natural biodiversity as a genetic reservoir to re-inoculate the pasture/economically productive areas after ecological disturbance.
We also determine farm productivity on what is our possibility rather than purely our wants. This encourages the small and slow solutions and encourages reflection on the decisions we make.
Other talking points.
We have a set of philosophies to guide our management decisions, not only for soil. These philosophies help keep us focused on ecosystem health and they move us along our farm succession to achieve our vision.
It is not appropriate to assess soils in isolation. Soils are an integral part of the whole farm ecosystem and must be assessed as such.
It is worthwhile identifying the similarities of varying soil and land management strategies. Lorraine Gordon has discussed the regenerative agriculture principles. It is important to understand that this site discusses our place-based decisions that are specific to the place we call Eaglerise Farm. They are not offered as claims of universal relevance. We encourage everyone to question our validity and absorb what is relevant. This is what makes food production so enthralling. It draws on our capacity for continuous, transformative learning.
My Mycorrhizal Fungi Story
Several years ago, I was in Hawaii to talk to some university people about some course linkages. Whilst there I attended an organic farming workshop. After some discussion on mycorrhizal fungi, everyone was given a small zip-lock bag of mycorrhizal fungi spores to take home and water through their market garden.
I thought, “Great. I’ll have a go at this!”
When I got back to our accommodation, I had two thoughts, “How am I going to get this small bag of white powder into Australia?” and, “How could tropical, Hawaiian mycorrhizal fungi possibly be suitable to the old, weathered soils at Mullengandra?”
I had the potential to introduce an inappropriate soil organism into my ecosystem – and the Australian ecosystem!
On reflection of this, I have compared it to the history of tree planting in Australia. After decades of ringbarking and killing trees, it was accepted that we needed trees back in the landscape. Many cypress pines were planted to provide shade and windbreaks.
After some time, it was realized that we really needed native trees for the ecosystem. This led to a wide selection of any tree as long as it was an Australian native. We had Western Australian flowering gums planted in eastern States for ecological diversity. These trees have much larger flowers and provide quite different ecological services than the locally natives.
It was then considered that we should be planting locally native trees. But a Murray River Red Gum is locally native, and it grows from one end of the Murray River to the other, over 2000km. Are there subtle differences, sub-species, growing with varying flower characteristics that have evolved within the distinct bioregion where it grows? Now we are encouraged to plant local provenance trees to match the local ecosystem requirements.
So, I ask, “Where should you source any soil biology from?” I suggest you look to your own farm and create your own local compost tea from your own local soil biology.