Getting a proper handle on crop nutrition will be key if growers going down the regenerative route want to reduce their fungicide use.
Kent farmer and regenerative agriculture adviser Andrew Howard told a Groundswell seminar that while approaches such as variety blends, inter cropping and healthy soils can all play an important role in reducing fungicide use, focusing on nutrition should be the first port of call.
“The elephant in the room is we use far too much nitrogen and excess nitrogen drives disease.
Profitable “If you’re trying to get 15 tonnes per hectare of wheat you will probably fail.
I’d rather grow a good crop of cheap, profitable wheat.
“At the moment I don’t think anyone would claim we have the knowledge to grow consistently, in every part of the country, 10t/ha of wheat without fungicides, although I think we’re getting close.”
After completing a Nuffield scholarship, Mr Howard decided to cut artificial inputs use on his farm by 50% in five years.
“We’ve pretty well done that while maintaining profit – fungicides have been one of the easiest [inputs to reduce].
“We have not had an issue in cutting [fungicide] doses in half or even more, but we are doing other things.”
For growers wanting to follow in his footsteps, Mr Howard suggested cutting out fungicidal seed dressings where possible as the first port of call.
“I would probably say fungicide seed dressings are not appropriate in regenerative agriculture, but when you are in transition and your soils aren’t yet healthy you might have to use them.
You’re trying to join the plant and soil, so to put a barrier in between seems a bit crazy.
When we’ve removed them, any problems we’ve had were down to nutrition,” he said.
Dressings NIAB agronomist Dr Syed Shah advised: “Use healthy seed, then decide whether you need a seed dressing.
If you look at the [research] papers, most seed dressings have a negative effect on soil biology, so if you don’t need it, don’t use it.”
There is not enough information on whether blends can reduce reliance on fungicides, he added.
“ I strongly believe in having the right nutrition.
– look at trace elements.
Manganese and copper, if applied at the right time will improve crop health, especially in allowing you to reduce incidence of mildew.”
Dr Shah also advised growers not to get “pulled in” by claims made for biostimulants, which could cost more than a good fungicide, but have little effect, he said.
“We have done a lot of work on biostimulants and there is some evidence that some biostimulants can increase green leaf retention or improve crop health, but if you have yellow rust, you will have to use tebuconazole.
There are so many [biostimulants] where you don’t really know if they’re effective and there is very little independent information.
“If you’re reducing reliance on fungicides with biostimulants, what is the cost of that product? In order to spend £20/ha on biostimulants it needs to make a difference.”
Mr Howard agreed: “Twelve years ago we held trials on-farm and the best margin was the lower dose of fungicide with nutrition.
For biostimulants, the most I pay if I use one is about £0.90/ha.
“For biostimulants that cost £25-£30/ha, you’re just swapping one cost for another.
You can be quickly dragged into a system where you’re spending more money and maybe get the same yield.
“This year I’ve done no T0 or T1 on wheat, a reasonable T2 and a low rate T3, but I wouldn’t necessarily recommend a farmer doing that in year one.”
As well as the role chemical inputs have in regenerative agriculture, the role agronomists and distributors would play moving forward was under the spotlight.
As more farmers show willingness to reduce their inputs and Government cracks down on pesticides, a key challenge will be how knowledge exchange is funded going forward, with independent institutes falling short of funding to address R&D, and input product sales currently driving a large proportion of crop production research.
Agrii agronomist Mark Dewes said: “It is a very imperfect system.
“If you look at distributors, a lot of work done that is interesting is not associated with product use, but the business model is not well set up to supply that.
“If you make your money through the profit of selling products and we move to systems where you sell fewer products, clearly the finance stream dries up.”
Although the UK is no longer in the EU, which has set targets to reduce pesticide use by half by 2030, Mr Dewes thought it unlikely it would escape the same pressures and he foresaw specific pesticide use reduction targets on the horizon.
Inputs He added that although he had no doubt agronomy companies would bring forward new and innovative services surrounding areas such as soil health, biologicals and genetics, he was aware farmers would not necessarily want to swap one set of inputs for a nonpesticide set of inputs.
“We’re looking at a more systems-based approach, not a product-based approach and that’s going to take a different level of support from the infrastructure that exists in the agronomy support sector.”
Andrew Howard said going forward he believed farmers would instead have multiple advisers, as they moved towards a knowledge-intensive, rather than input-intensive approach.
“Regenerative agriculture is such a huge subject you’re going to have a pesticide agronomist, biological agronomist, livestock adviser, soil scientist, environmental adviser and more.
Having one person you take advice from is probably coming to an end because not everyone can be an expert in everything.
Agronomy of the future will have to be above BASIS, FACTS and RB209.
Agronomists will need to look at brix, redox, electrical conductivity, tissue tests and sap tests.”
Much of this stems from an increased focus on margins over yields.
“One of my worries is going from selling pesticides, to biostimulants, to precision ag, giving us lots of data that we don’t know what to do with,” Mr Howard said.
“You’ve got to tread carefully as a farmer as to where you spend your money.
I also worry about models where agronomists share the margin as a performance matrix.
If they are part of that will they want to push change and push trials which might go wrong? I want my agronomist to be pushing me to do new things, rather than safe things.”
A lot of this will come down to the relationship between the farmer and the agronomist, Mr Dewes said.
“If you are an unaccountable decision-maker spending someone else’s money the temptation is to take a very risk averse approach.
If you’re involved in the risk assessment and you agree on the brief with your employer, you can take a group decision on the approach to risk.
“There is over-comfort that agronomists get in working for someone for 20 years – you’re looking at things and seeing the same problems, whereas a fresh pair of eyes often stimulates a different view on it.
We’ve got an enormously loyal customer base as agronomists and it gives us security we enjoy, but I do think that over familiarity stifles innovation.”
Gary Markham, LFB director, who runs a regenerative agriculture benchmarking group, said agronomists needed to look at total farm costs more, including machinery and labour.
He was seeing a move in the top performing farmers in his group taking agronomy in-house and then recruiting consultants who advise on regenerative agriculture.
“I see that is the future and that’s what I’m observing with our clients.”
The integration of animals into arable systems is one of the five guiding principles of regenerative agriculture, so it was unsurprising it was a recurring theme within the presentations at Groundswell.
Liz Genever, a beef and sheep consultant, pointed to sheep making a comeback into arable systems and she is facilitating this through her Carbon Dating initiative, which brings growers and livestock farmers together.
She said: “The redeployment of livestock during winter could help to meet demand from arable farmers who are looking for animals to graze cover crops and even winter cereals.”
However, David Miller, farm manager of Wheatsheaf Farming in Hampshire, said while he has used livestock to graze cover crops and increase organic matter in the past, there can be issues.
Poaching “Cover crops are often grazed down too short and during wet winters.
I would rather not have livestock poaching the ground but often it is necessary to commit earlier in the year.”
Cattle can also have a role in arable systems, said George Hosier, who uses a 200-head herd of suckler cows to graze cover crops on land which had not seen livestock for more than 40 years.
Mr Hosier believes cattle are the ideal grazing animals in an arable system, providing they are managed correctly.
He says: “We grow tall cover crops to maximise the quantity of biomass produced and so cattle do the best job of grazing them.
I move the cows every day to avoid poaching and as they have improved the ground, I have switched away from cultivations to a no-till system.
“We think the cows and the introduction of herbal leys into our rotation have had a significant impact on the grass-weeds.
“We have now cut out bagged phosphate and potash entirely.
We have reduced our nitrogen use each year by more than 70% and diesel use by more than half.
Most of our wheat has had no fungicide applied this year, compared to pre 2014 when we used up to four applications each year.
“Our wheat yield has declined, but only by on average half-a-tonne per hectare and last year we had our best year ever.”
Mr Hosier added.