In a rapidly changing world, New Zealand farmers will need to embrace agro-ecology, the science and practice of farming with an ecological mindset, to survive, the head of the BHU Future Farming Centre Charles Merfield told a recent webinar.
“The answer to life, the universe and agriculture is clearly to me becoming agro-ecology. If you’re not familiar with it you need to really get up to speed with this pretty quickly,” Merfield told Embracing Urban Agriculture, hosted by Lincoln University’s B Linc Innovation centre.
Merfield, who has more than 30 years’ experience in sustainable agriculture as an organic vegetable grower, consultant, teacher and scientist, said agro-ecology has been around for more than a century but has now been embraced by both the European Union and the United Nation’s Food and Agriculture Organisation (FAO).
“The whole EU strategy for agriculture for the next 10 years is based in agro-ecology,” he said. “And all the UN bodies, starting with the FAO over two decades ago, are now promoting agro-ecology as the future of farming.
“These are two massive supra-national political bureaucracies that require a vast amount of evidence, discussion and debate just to decide what to have for breakfast, so the fact they have moved from intensive agriculture and are now actively promoting agro-ecology is starting to scream volumes at me.”
Merfield said farmers have four “toolboxes” they can use: physics, chemistry, biology and ecology.
Agrichemicals are found in the chemistry toolbox.
“One of the things we find today is so many farmers and their predecessors are just embedded in the agrichemical method of farming. They are unaware that these other toolboxes even exist and there’s far more in the non-chemical toolboxes than there are in the chemical toolboxes in terms of ways of managing agriculture.”
Merfield has done extensive research on mesh covers to protect crops from insect pests and he led a field scale trial comparing the effectiveness of mesh made from woven fishing line with sprays for controlling psyllids on potatoes.
“The plots were 100m2 and we had one psyllid under the mesh, and over 400 on the chemicals. This is basically total control – you can’t get this level of control normally outside a lab.”
Despite a big upfront capital cost for the mesh, profitability in the trial actually increased, Merfield said, adding that mesh has been in use in Europe and Israel for 30 years.
He told his audience about other remarkable non-chemical ways of fighting insect pests, including a way to stop grapevine leaf hoppers from attacking grapes in Europe by disrupting their courtship song.
“They have to sing it and get it right before they mate and therefore produce larvae and if you disrupt this song, they can’t then mate and produce larvae.”
By attaching a small device that sends vibrations down the wires that go through the vines, that pre-mating song can be disrupted. “You disrupt the song, they can’t finish it, the boys and girls can’t mate and the leafhopper problem is solved.”
Merfield is convinced time is running out for chemical control, through evolved resistance, legislation and consumer resistance – but is equally sure that there are nature-friendly solutions.
“Where we need to get to is the redesign; this is agro-ecology,” he said. “We redesign the farming systems to be far more robust and resilient and give its multiple benefits — performance and profitability, reduce our planetary impacts and improve the overall robustness and resilience of the farm system in light of all these external shocks we are increasingly facing.”
