|Beneath the surface
with David Law
It began 17 years ago with a passion, and a belief that more grass can be grown with less synthetic nitrogen.
As a dairy farmer, I was using 150 units of synthetic nitrogen and growing 14 tonnes grass/ha. Ten years later, through a lot of experimentation and development, I was growing 19 tonnes grass/ha, using only 32 units of synthetic nitrogen.
All up, I had reduced my synthetic nitrogen use by 79 per cent and increased my pasture growth by 27 per cent.
It’s a bold statement, isn’t it? But I did it on our family farm, and we are in the process of doing it yet again – but in a dramatically reduced timeframe – through a unique and groundbreaking new programme we’ve called Total Replacement Therapy.
I left the farm in 2012 to enhance my passion, and I’ve spent the last seven years fine-tuning this process to get results quickly and efficiently.
My mission now is to regenerate the soils in New Zealand cost-efficiently and quickly, and to get the conditions ready for biology to activate change.
Total Replacement Therapy is the result of a team of international specialists combining their expertise in soil biology, chemistry, agronomy and nutrition.
The unique process gets clover fixing nitrogen naturally – the way it used to happen – so synthetic nitrogen can be switched off and replaced with the natural biological process.
We then introduce more biology and enhance their activity, which will help clover to replace artificial nitrogen and reduce farmers’ reliance on synthetic nitrogen.
But you can’t just go cold turkey with synthetic nitrogen; Total Replacement Therapy is a process with a set of steps that need to be followed.
Generally, we find that if you’ve been using a large amount of nitrogen there will be very little clover in your pasture, as synthetic nitrogen inhibits clover’s natural role of fixing nitrogen.
So the first, and biggest job, is to enable clover growth – before we can stop using synthetic nitrogen.
This is achieved by balancing the soil so the pH is ideal; there is a sweet spot where clover likes to grow and natural biology starts to work.
Then, rhizobia – diazotrophic bacteria that fix nitrogen after becoming established inside the root nodules of legumes – work with clover nodules to take nitrogen from the air and into the soil via photosynthesis.
Soil conditions need to be ideal, but there is technology available that will enhance the speed of this change.
Our team is at the point where we are confident to enter a meeting fraught with worried farmers, who are unsure whether their business will survive changing regulations, and say: “We can fix this.”
We felt the only way we could make the point was to prove it; our confidence in the success of Total Replacement Therapy is based on actual experience.
Only 21 days into our first on-farm trial, we’re seeing exciting changes occur: clover growth has increased dramatically and we’ve started to see the pink colour that is present when clover is fixing nitrogen naturally.
We are confident the results from this trial will produce firm evidence that farmers can grow more grass with less synthetic nitrogen, at a lower cost.
And the benefits of Total Replacement Therapy also extend to reducing methane and leaching, as well as increasing water-holding capacity in the soil.
The reality is that things are changing, and farmers will be legally obliged to change their nitrogen habits. And we can help in this situation without any upset to farmers’ profitability.
We feel we have an obligation to share our knowledge; the fruit of our wider team’s many combined decades of experience, research and trial work.
Total Replacement Therapy works, I have no doubt about that. But we are completing comprehensive monitoring – of pasture composition, worm population and soil structure, as well as regional council-sanctioned water and emissions testing – to ensure we can back up our claims with hard evidence.