South Fremantle market gardenerLori Sumich with Ausplow's Engineering Manager Carol Erasmus  discussing deep tillage.

South Fremantle market gardenerLori Sumich with Ausplow's Engineering Manager Carol Erasmus discussing deep tillage.

Healthy celery roots are evident int his high-yielding letrtuce bed which was deep tilled after the crop was sown.

Healthy celery roots are evident int his high-yielding letrtuce bed which was deep tilled after the crop was sown.

By JOHN RYAN AM
Chinese philosopher and teacher Confucius had it right in 400BC when he famously declared: “The ox is slow but the earth is patient”.
It’s a fairly accurate analogy of agriculture, which in broadacre terms in Australia, only came of age, so to speak, a little over 60 years ago.
The ox, in this case, is the universal farmer, who only knew what had been passed onto him or her from previous generations, hence the oft-quoted, “it’s the way I was taught”.
But there also were oxen, the early ‘tractors’ of agriculture, allowing a farmer to walk behind with a wooden plough and later a cast iron wheeled mouldboard plough invented by the Romans, horse-drawn versions of which persisted in Europe into the early 20th century.
Interestingly, the Chinese discovered that so-called mouldboarding turned over the upper layer of the soil, bringing fresh nutrients to the surface while burying weeds and the remains of previous crops and allowing them to break down.
Sound familiar?
The age of mechanics in the early 1930s accelerated this practice (of mouldboarding) and brought heartache to farmers experiencing droughts in the Midwest and southern Great Plains of the US (Montana, North Dakota, South Dakota, Wyoming, Nebraska, Kansas, Colorado, Oklahoma, Texas, and New Mexico) and the Canadian Prairies (Manitoba, Saskatchewan and Alberta).
Massive dust storms and severe drought saw the period from 1930 to 1940 to become known as the ‘Dust Bowl’ years in those States.
In Australia, our short history of broadacre and dryland farming is well documented in terms of soil degradation, caused by naturally poor soil structure, tillage and over-grazing.
And despite the evolution away from work-up and work-back, to direct drill and no-till, problems persist, including wind erosion, acidity, salinity and perhaps the biggest problem of them all, nutrient imbalance.
The point of this historical treatise is to remind DBS owners they are in possession of a tool to slowly assist our patient Mother Earth.
And it may surprise some owners to know that the genesis of the DBS was the result of my work in market gardens, working with Lori Sumich in the 1980s when I was involved with Agrowplow, a deep ripping machine I designed in the late 1970s.
In those days, deep ripping didn’t hold much sway with the then Agriculture Department and I remember a researcher telling me we didn’t need deep ripping in WA because it consisted of a 50 foot deep sandhill.
That wasn’t what I found in Lori’s vegetable beds. Tell-tale lateral root growth was very evident in the market garden beds, highlighting soil barriers – compaction from rotary hoeing, natural settling of the soil and rain (in broadacres areas you can add vehicle trafficking and aluminium toxicity).
But after a rip I found sand would collapse after a heavy rain and the barrier would reform.
That’s what got me thinking about using plants roots as scaffolds to hold soil together in a loose structure which provided pathways for air and moisture and root access.
I couldn’t eliminate rotary hoeing in the vegie beds because it was the main tool for killing weeds and re-shaping the beds after crops had been harvested.
So the compromise was to follow-up with ripping once the plants were established.
The rip didn’t affect the plants and we found the roots grew quicker and went deeper and our first trial, in fact, saw a doubling of celery bunch size.
We put this down to adequate moisture and fertigation, which combined with new root pathways from ripping - providing air and moisture pathways - stimulated biological activity in the soil.
The key here is that what I call the ‘scaffolding effect’ function of plants roots to create a more porous soil structure – much like you get when you buy a bag of potting mix.
Hence came the pot plant analogy for broadacre plant establishment and the three slot system of the DBS – create a rip (or poke your finger into the potting mix), place the seed precisely in the rip on loosened soil (using a parallelogram system integrating the seeding boot) and tamping it down with a press wheel (your fingers in the case of a pot plant).
Our first trials with a prototype DBS proved the three-slot system worked and from then on it was a matter of refining the system to deliver precise product placement of seed and fertiliser (either deep banded or a split application for starter fertiliser with the seed).
We did more work with Lori and found that where we retained old roots in the soil, the vegetables increased in size.
I remember seeing lettuce which grew like a round ball rather than the flourish of leaves which you discard when you pick your choice in the supermarket.
Lori was at first critical that the system wasn’t working properly but an inspection of the ‘firm, round ball’ lettuce showed it to be healthier than conventional plants.
It was readily apparent to me that the pot plant-type soil environment of the vegie beds could be replicated for broadacre crop establishment.
And this spurred on the research and development of the DBS as a tool to create a soil environment which enhanced the ‘scaffolding effect’.
The role of roots is complex but simply put, in the right environment of moisture and air, root hairs interact with the micro-organic ‘community’ in a symbiotic relationship which builds soil structure.
Many DBS owners have told me their soil is getting softer and more structured and the tell-tale sign in the soil’s ability to hold moisture.
The action of the DBS and the resultant hill-valley finish for water harvesting, is in fact encouraging rain to stay where it falls as moisture is held by organic matter or humus.
(How many DBS owners have trouble filling dams on their properties because they no longer get run-off and have had to build roaded catchments)?
The other benefit of the DBS three slot system is that it allows the leaching of salts beyond the root zone although in some soil types hardpans or re-forming hardpans will need to be addressed for this successful leaching.
If you’re tackling re-forming hardpans you probably only need to dig down to about 175 to 200mm and you can achieve that with the DBS.
Remember, with our new Pro-D system, you can put the DBS to work as a renovator, particularly where you want to stimulate tired pasture paddocks and re-generate strong plant growth.
We have DBS owners already doing that of renovation and then seeding deep-rooted tropical plants and grass varieties with fibrous roots.
The other aspect of the DBS is its ability to establish crops in a dry start.
It’s probably one of the main areas of feedback I get when I speak with owners who talk about the ability of going in dry and wetting up seed beds.
The cultivation below the seed can tap into subsoil moisture which rises under pressure to the surface – it has given a lot of owners more confidence in establishing crops, particularly canola, which is prone to wet-dry scenarios resulting in staggered germinations.
So we’re finding that with the DBS, the importance of developing a moisture-holding soil structure is so important to healthy microbiology.
Picture eating an apple and putting it on the table. Pretty soon the apple starts to go brown.
That’s because there’s oxygen and moisture present which is the perfect environment for bacteria to operate.
This is the same sort of action that occurs in the subsoil with bacteria ‘alive’ in the presence of air and moisture.
There’s an old analogy that says you can only hold your breath for so long before you need air to live. That’s a similar case for soil.
As seeding programs start to kick off, I want to wish everybody an enjoyable and positive season.
And I would also encourage you to assess the benefits of liquid fertilisers and soil ameliorants.
Do a few trials to start with to see what works in your paddocks. Liquids to me seem to be the way to go and it was a major reason why I designed the Multistream liquid delivery system to provide farmers with some flexibility at seeding.
With the improvement in mapping programs and software applications, adopting a more flexible approach to your cropping programs, which could include variable product rates, is a good pathway to increasing farm profit.
So I just encourage more experimentation based on the proven principles we have established with the DBS system.
The more you farm using DBS principles the better your soil will get and the more money you will make.
Perhaps Confucius then might produce a new saying like: The ox is getting it and the earth is happier.

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Publish Date: 
Saturday, May 4, 2019