The BHU Future Farming Centre

Information - Launch of the FFC

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The FFC was launched on the 31 October 2011 at Lincoln University, with a public lecture titled 'A New Agricultural Testament' and an official opening by Tom Lambie, Chancellor of Lincoln University, organic farmer, former National President of Federated Farmers and Commissioner at Environment Canterbury.

Information about and recordings of the launch is avalible in a range of formats.  The text formats do not include the opening by Tom Lambie, while the audio and video recordings do. 

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Microsoft Powerpoint of lecture including both slides and text (in speakers notes pages) (20MB)

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A New Agricultural Testament

A New Agricultural Testament

Thank you and welcome to the launch of The BHU Future Farming Centre and this lecture ‘A New Agricultural Testament’
This lecture is something of a hydra, it is part science, part philosophy, part politics, part history lesson, and part acknowledgement of a few of the giants on whose shoulders we all stand. Its aim is to paint a picture of agriculture in the widest sense and context possible, and look at a few key issues, as a means to explain and explore the ideas that underpin the Future Farming Centre and therefore what needs to be done, to ensure the future prosperity of agriculture, and therefore society as a whole. This is a big and audacious aim, so, as this is one lecture, not a whole degree, I will not be able to delve into detailed arguments, only touch on a few topics, some controversial, leaving you to fill in the gaps. To that end it is also clearly meant to be a stimulus to further discussion and debate, not the final word.
Also a quick clarification: I will use the terms agriculture, farming, farms and farmers in the broad meaning i.e., they include all the primary industries e.g., horticulture, forestry etc. but for the sake of brevity I will use agriculture and farming as proxies.

Agriculture at a crossroads

The last century has been one of great turmoil for agriculture, and human civilisation as a whole. The dominant form of agriculture during this time, called industrial agriculture, as it attempts to mimic the production line processes of the industrial revolution, is now increasingly being called into question. The most substantial of this recent criticism came from the ‘International Assessment of Agricultural Knowledge, Science and Technology for Development’, the closest thing agriculture has to the Intergovernmental Panel on Climate Change (IPCC). The conclusion of the Ag-assessment was that “Farming is at a crossroads” and that “business as usual is not an option”: farming can not continue down the industrial path, it has to turn to the ‘alternative’ paradigms such as agro-ecology and organic agriculture.
This is not, however, some ivory tower dialectic: despite the astonishing changes that science and technology have made to human society, civilisation is still as utterly dependent on agriculture as at any other time in history and there is little indication of the sun setting on agriculture any time soon. It is therefore as far as you can get from an academic argument, it is one of the most important and practical problems facing us today.
It is also not a new argument: the debate has been engaged since the earliest days of industrial agriculture, fiercely at first, then meekly during the middle of the last century, especially post the second world war, but more recently with renewed vigour, as wider society starts to comprehend that industrial agriculture’s chickens are coming home to roost.
I now want to highlight two early protagonists of this debate.

An Agricultural Testament

71 years ago, Sir Albert Howard published ‘An Agricultural Testament’ from which this lectures title is taken. Testament is one of the key foundation stones upon which the global organic movement has been built. Most of the book is an argument, built on a lifetime of practical farming and agricultural science experience, that the reductionist ‘NPK’ approach to crop nutrition, which was based on Liebig’s discovery that plants take up nutrients as soluble minerals not organic matter, was fundamentally flawed, and that a different path should be taken, namely of treating soil as a biological entity not just a container to hold minerals for plants. Basing this lectures title on An Agricultural Testament is an acknowledgement of Howard’s immense wisdom and vision despite the contrary mainstream view, and that most of the concerns he raised are still critical contemporary issues.

Farmers of Forty Centuries

Exactly one hundred years ago Professor Franklin King’s “Farmers of Forty Centuries” subtitled “permanent agriculture in China, Korea and Japan” was posthumously published. This work is also widely considered a classic in alternative agricultures, which is interesting as King was part of his day’s establishment.
FoFC first introduced the concept of ‘permanent agriculture’ to a wide audience and it is from this work that the Future Farming Centre has taken the term, and the concept, of permanent agriculture, and made it, its foundation. It is the issue of permanence in agriculture that this lecture primarily addresses. Unfortunately, little of Prof. Kings wisdom has made it to the mainstream, either, and it is becoming increasingly urgent that his and Howards ideas become more widely understood.
Permanent agriculture is a complex topic so I am going to take handful of examples to explain what I mean. First, however, It will also require a bit of context.


‘Permanent’, along with the related, and now rather muddied, word ‘sustainable’ are terms relating to time. Without stating the time period in consideration they are pretty meaningless. So in good philosophical tradition, I’d better define my terms. To give a feeling for how I consider permanence in the context of agriculture, I’m going to give you a very, very brief history of time.

A very brief history of time

The universe, and time with, it began 13.7 billion years ago and about 9 billion years later, our solar system formed, making the earth 4.5 billion years old.
Life appeared on earth very pretty much as soon as the place had cooled enough for liquid water to exist, around 3.5 billion years ago. However, for about 85% of the life of life, life was pretty simple, or to be exact singular: for 3 billion years the microbes had the planet to themselves. Then about half a billion / 500 million years ago, multicellular life burst onto the scene in the evolutionary creative orgy of the Cambrian explosion.
It took evolution 498 million years from the start of multicellular life, or 2.4 million years before present, for the first members of our genus Homo to appear. From there it took 2.2 Myrs to create the first Homo sapiens but it was only 50,000 years ago that fully behaviourally modern humans appeared.
Even though those first fully modern humans had all the cognitive equipment to create agriculture, that did not happen for another 40,000 years / 10,000 years BP. Agriculture, therefore, is truly a new kid on the block.
However, if agriculture as a whole is a new invention for H. sapiens, then, industrial agriculture - modern farming, is a real flash in the pan, being barely 100 years old. Even the modern way of thinking that started in the Enlightenment, of which science is a key foundation, and which is essential for the creation of industrial agriculture, is only a couple of hundred years old.
Even with the rapid speed of progress with which we are currently living, it is difficult to comprehend this exponential acceleration of the processes that have lead to our current situation. The world we find around us, which we consider to be normal, is very far from normal at all, it is the most abnormal situation that has ever existed in the entire history of everything we know. The experiences we collect during our day to day lives, and ‘common sense’ are unreliable guides to understanding the present and future. The best tools we have are the lenses of science and reason, bestowed on us by the Enlightenment. It can be argued that we are standing at the early dawn of a new epoch in human history, which can be divided into our species birth, appearance of cognitively modern humans, the advent of agriculture & civilisation, and the enlightenment. The enlightenment as changed humanity in ways that were previously impossible and inconceivable, yet we as a species and society are still struggling to understand its effects. We gaze into a future where the past is a very poor guide indeed.
This is a truly grand perspective, and while it is essential to understand just how abnormal agriculture and especially industrial agriculture are, it is rather too grand for the job of defining permanent agriculture.

The duration of farming

The time span I believe we need to think of, is that of our existence as a species. We, Homo sapiens are 200,000 years old. The average life of a species is about a 1,000,000 years. If H. sapiens, survives for this average duration, even though we as a species are anything but average, then we have another 800,000 years to plan for, i.e. four times longer than we have already existed, and 80 times the duration of agriculture.
As Niels Bohr pointed out, making predications is hard, especially about the future. Predicting 800,000 years into the future is nonsense: we may have achieved faster than light travel and colonised multiple galaxies, we may still be stuck on planet earth, or we may no longer exist at all.
So while 800,000 years is a bold figure to demonstrate the magnitude of the issue, it is however, so far in the future that it is beyond fiction. It is also a length of time that most people are completely unable to comprehend, let alone intuitively. We need a time scale that indicates the issues we face without being so big, as to be meaningless.
For this I suggest one millennium, i.e. 1,000 years.

Dirt: The erosion of civilisations

The concept of a millennium as the fundamental unit of permanence in agriculture is taken from Prof. David Montgomery’s book ‘Dirt: The Erosion of Civilizations’. His thesis is that most human civilisations have a maximum duration of about 1,000 years as this is how long it takes them to destroy their soils, and as Wendell Berry pointed out, “what we do to the land, we do to ourselves”.
Montgomery is not the only person to point out that human civilisations have a habit of destroying their foundations: Plato, said as much in 400 B.C. and it is a key thesis of Prof. Tim Flannery’s ‘The Future Eaters’. Put simply, nearly every human civilisation from the very first to the present, destroyed itself, by destroying its soil. This is why ‘Farmers of Forty Centuries’ or to use our new timescale, four millennia, is such an important message: these are the only farmers that are part of civilisations, in the whole history of civilisation, than have achieved permanence. Everyone else, including ourselves, has stuffed it up.
I therefore suggest that agriculture needs a foundational ethic.

The first ethic of agriculture

“The primary task of agriculture is good husbandry of the soil, such that soil ‘quality’ / ‘health’ is maintained or improved at timescales of millennia”
There have only been ten millennia since the start of agriculture, there are another 800 to go if the lifespan of H. sapiens, is anywhere near average. If we, as a species don’t get this right, now that we are farming practically all of the farmable areas on the planet, we are sealing our own fate.
To fully understand this issue, we need to understand some first order explanations of how agriculture and the planet works.

The earth machine

Looking through the lens of the most fundamental of laws, those of thermodynamics, the earth is a giant entropy ‘excreting machine’. It uses the energy flowing from the sun across the earth and out to interstellar space, to ‘export’ entropy to the universe. This allows it to create low entropy, i.e., complex, things such as life. This process is the foundation of the concept that James Lovelock named Gaia.

Matter cycles

The complex things the earth machine makes by excreting entropy, are made from matter i.e., the chemical elements of which the planet, and the rest of the universe, is formed. The key concept here is that energy flows, but matter cycles, and cycles and cycles.
Scientists have a habit of creating complex jargon, partly due to that human need to maintain oneself with the ‘in-crowd’ but also because we are pedants for accuracy. One of those terms is biogeochemistry - which is the science of the chemical, physical, geological, and biological processes that govern the composition of the natural environment. The chemistry of biology and geology. I suspect that most people would think that the chemistry of biology and geology have nothing in common. Nothing could be further from the truth. As Lovelock pointed out, the geology and biology of the planet are part and parcel of the same system. Therefore understanding the biogeochemical cycles is essential for understanding the planet.
So, what has biogeochemistry got to do with farming? Farms are microcosms of the planet as a whole. They use sunlight to power photosynthesis which creates complexity from the chemical elements by excreting entropy to the universe, exactly the same as the planet as whole. That is why we can not understand farms until we understand how the ‘earth machine’ works.
It also gives us the fundamental measure to tell us if our farming systems are permanent or not, because if they are not working with the earths systems, they are working against them, and sooner or later, they will break, because, as Lynn Margulis pointed out "Gaia is a tough bitch“ she is much tougher than humanity and we will loose any battle we try to wage on her.

Industrial ag / green revolution

Keeping in mind the picture I have just painted, I now want to turn to the fundamental technologies that power industrial agriculture, and one of its key philosophies, the green revolution, to see how they fair against the yardsticks of a millenia and working with the biogeochemical cycles, and therefore to act as a contrast with permanent agriculture.
The technologies that power industrial agriculture are: fertilisers, particularly nitrogen, pesticides, irrigation and breeding.
I want to focus on the most important of these: fertilisers and pesticides.

The elements of life

First fertilisers. Once again we need to think beyond our day-to-day understanding of ‘fertilisers’.
Of the 94 naturally occurring elements, only 24 are used by life, and most of those are only used in small quantities: life is mostly carbon, hydrogen and oxygen, for example, they make up 96 odd percent of plants. It is therefore very fortunate that these three elements cycle via the atmosphere, as this means they are freely available so we don’t have to apply them to crops as fertilisers - which is why they are not commonly thought of as fertilisers at all. All the other elements, except for nitrogen, are lithospheric nutrients, i.e., they don’t occur in gaseous forms so they can’t cycle via the atmosphere, they can only cycle as solids, via the rocks of the earth.
If the elements of life were a pack of cards, carbon, oxygen and hydrogen would be the royal cards while the lithospheric nutrients would be the numbered cards, and nitrogen would be the joker.

Nitrogen the joker

Nitrogen is the joker of the biogeochemicals, because it is an atmospheric nutrient, indeed uniquely the main planetary store is the atmosphere, but, most life can not make use of atmospheric di-nitrogen, it can only use reactive nitrogen where di-nitrogen is combined with hydrogen.


Turning di-nitrogen into reactive nitrogen is very, very hard, due to the laws of thermodynamics and quantum mechanics. There are only a couple of handfuls of mostly primitive, single-celled, organisms that can do this and they all use essentially the same enzyme - nitrogenase, which means that just about all of life on earth depends on this one molecule. Even evolution, with all its power and 3.5 billion years to play with, has only found one solution to this problem, which is pretty scary.

Haber-Bosch nitrogen

However, one hundred and two years ago, Fritz Haber discovered a practical, economical, non-biological, means of fixing di-nitrogen, and with the help of Carl Bosch industrialised the process. No other practical and economic means of synthesising reactive nitrogen have been discovered in the intervening century, and not for want of trying.
The Haber-Bosch process is considered to be one of the most important achievements of the 20th Century, with some arguing it has had far greater impact than Hitler, Gandhi, and Einstein, (see However, synthetic N has turned out to be something of a double edged sword, which is why I describe it as one of humanities greatest follies.
Synthetic nitrogen is one of the key foundations of industrial agriculture and the green revolution, because, in most agricultural systems N is the limiting nutrient. The main aim of the green revolution and industrial agriculture has been the production of more food, by increasing yields, with the aim of feeding a growing world population and therefore avoiding Malthusian starvation. There is little argument that it has achieved its general aim, but there is a growing realisation that the unintended consequences are a bigger problem than the solution.

Thomas Malthus

The first, and rather politically unpalatable, issue is that it is impossible to unendingly increase food supply to match unconstrained demand. Fundamentally Malthus was, without doubt, correct; living things will multiply up to the limit of their food supply and then their population will crash.
Despite disbelief of this idea, especially in mainstream economics; biological and ecological scientists see its effect everyday, from cultures in Petri-dishes, to large scale ecosystems. It is also one of the key tasks of a livestock farmer to manage their stock numbers within the Malthusian limits of what their farm can produce, and if there are too many animals, remove the excess, not buy more land for the extra stock. The flow of energy from the sun is from the bottom-up, i.e., from plants, up through the food chain, not down from humans to plants. This is not a vague political concept, it is very hard physics, and as Scotty often said to Kirk, “you canny break the laws of physics, Captain!”
So the effect of using Haber-Bosch nitrogen (HBN), was not only to feed the current population, it also allowed the population to increase beyond what it could of done without HBN. Today is the day the UN has estimated the worlds population has reached seven billion. This is difficult territory, but some estimates calculate that there are an extra 3.5 billion people on the planet today due to HBN, i.e., half the worlds population only exist because of HBN, i.e., it has not solved the problem at all it has only made it bigger.
Fundamentally the argument that we need to increase food supply to match a particular population is a classic example of the logical error of the cart in front of the horse. If humanity considers itself to be in for the long haul, i.e., for millennia, not decades, then the way forward is to manage agriculture so as to ensure its permanence and then to manage the human population to match agricultural output. All the technical solutions to solving world hunger by increasing food supply are all fundamentally flawed: if they succeeded they would in fact make the problem worse.

Nitrogen - made from thin air?

Returning to the problems with nitrogen. It is not just that Haber-Bosch nitrogen has doubled the number of people on earth, there are a host of other problems with synthetic N.
Nitrogen fertilisers are made from ‘oil’ i.e., fossil fuel, mostly natural gas. This supplies both the considerable energy needed and hydrogen to make reactive N. The N itself comes from the air for free. However, about 1.5% of global energy supply and about 6% of global natural gas supply are used in the Haber-Bosch process to make reactive N, most of which is used to make N fertiliser. It is no surprise then that the price of nitrogen fertilisers moves in lock step with oil, because they are both metaphorically and literally made from ‘oil’.
As peak oil is now widely taken as a given, this is a clear problem for the production and use of nitrogen fertilisers as the price can only go up and supply down. If we apply our permanent agriculture yardstick of a millennium to the idea of making N fertiliser from fossil fuels, then it comes up pretty short - one century so far, and its looking pretty unlikely that it’s going to last for another one, let alone another nine centuries.

The nitrogen deluge

The next problem is that nitrogen fertiliser does not stay put in farmers fields, it has spread across the whole globe producing a cascade of side effects. The European Nitrogen Assessment, published this year, is nearest thing to Nitrogen's IPCC. It lays out our best current understanding of nitrogen and its side effects, including, I quote “human health, ecosystem health, biodiversity and climate”, i.e., pretty much everything. A few examples of these effects are eutrophication of water, both fresh, and salty e.g., oceanic dead zones, greenhouse forcing from nitrous oxide, and acid rain.
This is the big reason why I think of nitrogen as the ‘joker’ it has a multitude of different chemical forms, having different properties - nutrient and pollutant, greenhouse gas and non-greenhouse gas, enemy and friend. All these problems are effects of humanities short-circuiting of the biogeochemistry of nitrogen, in the hubristic belief that we know what we are doing.
I suggest that we need a new relationship with nitrogen based on a realisation, that it is a joker, a double edged sword, and that treating it with precaution rather than hubris, is probably the wiser thing to do.

The lithospheric nutrients

I now will touch on the lithospheric nutrients. These are nutrients such as phosphorus, potassium, magnesium, etc., that are commonly considered to be ‘fertilisers’ in agriculture. Again, they are lithospheric nutrients, because on earth they don’t have a gaseous form, so they can only cycle via the rocks of the earth, i.e., the lithosphere, not the atmosphere. This puts a pretty serious time constraint on the speed of the cycles, because while the rocks of the earth move, as we have recently been reminded in Canterbury, they only move by appreciable amounts in timescales of tens of millions of years, i.e. time scales much bigger than our estimation of H. sapiens life span of 0.8 million years.
Using phosphorus as a proxy for all the lithospheric nutrients, from the perspective of agriculture, its cycle can be divided in to two parts, the soil cycle, and the litho/hydrosphere cycle. The cycle in soil can be pretty fast, as phosphorus is taken up by plants, which then die and return the phosphorus to the soil. The litho/hydro cycle involves phosphorus that enters streams and rivers, where it is then transported to the seas and oceans. There, it settles out as sediment, which then turn into rock, which is uplifted by plate tectonics above sea level, where it can then be eroded to release the phosphorus back to the soil. Clearly this cycle is rather slower than the soil cycle.
The problem we currently have is we are short-circuiting the cycling of the lithospheric biogeochemicals, by transferring them from the soil to the sea at unprecedented rates. This is both directly, e.g., by runoff and leaching from land, especially farmland, but also by another of humanities most successful follies, the water closet.
The WC was invented to solve a number of communicable disease problems, and on that front it has been very successful. However, people, such as King and Howard, have been pointing out, that it had the significant downside of transferring nutrients from the soil to the sea, on what in human timescales is effectively a one-way trip.

Fossil fertilisers

That is why the current system of agricultural fertilisation is fundamentally flawed. It is based on mining fossil nutrients, first in the form of guano and currently in the form of rocks, such as rock phosphate, which were laid down in shallow seas 10s to 100s of millions of years ago. This means that they will have a peak in supply, just like oil. Trying to predict peak phosphorus, peak potassium, etc., is difficult, but current ballpark figures for phosphorus is 70 years and potassium 400 years. Seventy and especially 400 years sound like a long time, but, based on our yardstick of a millennium, 70 years is a flash in the pan and 400 does not even get us half way.
Worse however, our short-circuiting of the lithospheric biogeochemical cycles is a fundamentally different problem to our short circuiting the atmospheric biogeochemical cycles of carbon and nitrogen. Unlike the changes to the atmospheric cycles, which from a scientific viewpoint can be pretty easily reversed, due to the rapid cycling time, it just needs the political determination and money. The same is not true of the lithospheric cycles, once these elements are lost to the bottom of the ocean we have no conceivable practical way to get them back, in anywhere near the same amounts that we are putting them in. As numerous highly qualified people have stressed, there are NO economic substitutes for the chemical elements in agriculture, period. Once we run out, we have run out, end of story. Once agriculture runs out of nutrients, it grinds to a halt. If you think climate change is a big problem, then humanities short-circuiting of the biogeochemical cycles of the lithospheric elements, is of a completely different magnitude and type.

What's the solution?

So, what’s the solution? Well humanity has known about the solution for a very long time.
Prof King showed that the answer has been fully understood by farmers in the east for at least four millenia, probably more. In today's parlance, the solution is that we must ensure all the lithospheric biogeochemicals removed from soil are recycled back to the soil within human time scales, i.e. years, and done in such a fashion that maintains, or better, improves the biological functioning of the soil. Scientifically this is about as simple as things get, but at a practical and political level, it is very hard indeed. Trying to get across to the general public and politicians that Haber-Bosch nitrogen and the WC are a curse on our civilisation has to date, proved impossible.
I am now going to leave fertilisers and look at that the problematic technology of pesticides. I’m using pesticides in the broad meaning which includes herbicides, fungicides, insecticides etc. I’ll start with a couple of quotes from key players from my speciality of weed science.

There is no cavalry

Dr Anne Thompson, is Head of Development and Registration at Dow AgroSciences. She was speaking at the ‘The Future of Weed Research’ workshop held in the UK in 2008, with a mandate from the agri-chemical industry. Said she had a message to pass onto farmers, as they did not seem to understand the situation. Her message was very simple:
“Please tell the farmers there is no cavalry coming over the hill.”
She was equally transparent that the agrichemical industry is in the business of making money, not making pesticides, and that unless a pesticide is profitable, which almost certainly meant a tie-up between transgenetic (GE) crops and propriety pesticides, then farmers should assume there would be no new pesticides.
To reinforce just how big a deal is, this was the horses mouth of the agrichemical industry saying the agrichemical game is over.

The post herbicide era

Dr Jon Marshal, is the editor of the world’s leading weed science journal, ‘Weed Research’. In his landmark editorial to celebrate half a century of the journals publication, he introduced the concept of a post-herbicide era. Weed science, and its journals, have been almost entirely dedicated to herbicide science not weed science, for their whole existence. For the editor of a journal that been dominated by herbicides to say on such a important occasion, that he can see a time when there are no herbicides at all, is jaw dropping.
However, the message is the same for all the pesticides, and it is being spoken by an increasing number farmers and scientists. What’s more we may well already be past peak pesticides, in terms of the number of chemicals available and/or the amounts being used. So, what is causing this increasingly rapid change?

A pincer movement

Pesticides are caught, to use their own militaristic terminology, in a pincer movement.
First: they are being rendered ineffective by Darwin's law of evolution.
Second, The lack of new chemistry is not for want of trying: the whole business model of the agrichemical industry was dependent on the discovery of new chemistry. New chemistry is simply not there to be found.
Third and final, societies are re-evaluating the cost : benefit analysis of pesticides, and increasingly viewing the costs as outweighing the benefits.
The issues of evolved resistance and lack of new chemistry are mostly the results of the laws of nature, so we can study them and understand why we are unlikely to see current trends reverse. The issue of societal acceptance is not fundamentally due to laws of nature, it is down to ethics, so it is impossible to predict, and it can do a U turn as circumstances change. However, that will be of limited use if there are few effective pesticides left to re-legalise. 
So, using our millenium measure, how do pesticides stack up? In round figures, the widespread use of pesticides started in the 1940s, so we have had about 70 years of extensive use. If we have already passed peak pesticides, their effective lifespan at a guestimate will be similar, so a total duration of, say, 150 years, which is 850 years short of being permanent. We had therefore better find alternatives that are truly permanent solutions to pest management. What are these?

The integrated management framework

My perspective of looking at this issue, is through the well established framework of integrated pest management, where physical, chemical, biological and ecological techniques are all brought to bear on the pest problem in a whole-of-system approach. From this perspective, chemical pesticides, are only one of three management techniques, i.e., there are still plenty of options left. The problem is that research on non-chemical techniques effectively stopped with the advent of chemical pesticides, i.e., there has been a 70 odd year research hiatus, which means that the amount of knowledge is comparably much, much, less than chemicals.
What's more, few non-chemical techniques are as easy to use as agrichemicals - many only work as part of an integrated solution and require system level changes, e.g., from monocultures to rotations and polycultures, which will require significant changes to industrial agricultural practices, which, ipso facto, means such farming systems are no longer industrial, they are ecological.


Fortunately, despite the lack of research over much of the last century, great progress is now being made, for example the Bio-Protection Research Centre, HQ’ed here at Lincoln University, is conducting world-leading research in this area.

The post-industrial agriculture era

To conclude this part of the lecture, I have shown how the two key technologies that underpin industrial agriculture, mineral fertilisers and pesticides, are unsustainable, i.e., they have very limited durations compared with the lifespan of agriculture, plus they have multiple side effects, some which now threaten humanity.
Globally there is a realisation that agriculture has to change from the yield maximisation ethic of industrial agriculture, to wider objectives such as provision of ecosystem services.  In many places, including NZ, it is already changing. Industrial agriculture can be viewed as 100 year long experiment that is now increasingly considered to have failed. I suggest that we have already passed peak industrial agriculture sometime in the last twenty years. So, what is the alternative going to look like? Well, if you strip industrial agriculture of its ethic of yield maximisation require it to use recycled soil nutrients and non-chemical pest management, what do you have? Organic agriculture!

Ethics, science and agriculture

Having looked at some of the problems of industrial agriculture I now want to turn to ethics and its relationship with science and agriculture.
I consider this to be a utterly vital area of knowledge, but it is one that practically never gets an airing, even within the rarefied atmosphere of universities. I therefore need to spend a little time explaining the basics so we are not talking at cross purposes.
First up, for our purposes, ethics and morals are interchangeable as terms, even though moral philosophers have more precise meanings as per this slide. For our needs morals and ethics are the things that tell us if something is good or bad, right or wrong.
Firstly, I am not just talking about current and obvious moral issues, such as: is it ethical to keep chickens in cages. I am talking about the moral codes and values that underpin our ethical world-views as societies, e.g., slavery is wrong. Unlike the current moral dilemmas which are consciously debated, moral codes mostly operate at a sub-conscious levels, i.e., while there is a lot of debate about whether keeping chickens in cages is right or wrong, there is no discussion that slavery is wrong, it is taken as a given. The problem with these foundational ethics is that they are mostly subconscious so we often do not realise that they are moral or ethical decisions at all, they are just ‘how things are’ and therefore often mistakenly considered to be ‘how things have always been, and always will be’.
The issue with such foundational ethics is when they start to change, confusion is often the result. I consider it a particular problem when these changing morals get mistaken as scientific concepts. The issue is trying to find a rubric for spotting the difference. This is mine…

It is unscientific not to use slaves on farms

It is unscientific not to use slaves on farms, their use increases yields and profits.
I hope that the modern absurdity of this statement make the intellectual slight of hand that was used jump out. The use of slaves is clearly an ethical issue not a scientific one. However, if we were living 300 years ago at the height of the slave trade, were modern science around, it could be used to work out how to maximise the output of slaves, and what would happen if you stopped using them, but it could only be utterly silent on whether using slaves was right or wrong.
This is an example of what I mean by confusing science and ethics. The way to use this as a rubric is to change the term ‘slaves’ for some other term, for example, tillage, pesticides, nitrogen fertilisers, the internal combustion engine, or GE. Philosophically, these are just as valid concepts to put into this statement as slaves. They are also real world examples, in that there are real farming systems deliberately operating without one or more of them.

Francis Bacon

At this point it is really critical to understand the incompatibility and relationship between science and ethics.
Theoretically just about everything in the universe is amenable to the scientific method. Practically we have lots of problems, e.g., physicists dream of particle accelerators the size of the milky way, but at a theoretical level just about everything can be studied by science, except, matters of right and wrong, good and bad, i.e., what is ethical and moral. This is not news, Francis Bacon who established the inductive methodologies for scientific inquiry, clearly said that ethics forever lay outside of science. There are many others since his time that have elaborated further, e.g.,

Impossibility, the limit of science and the science of limits

For example, John Barrow in he  book, “Impossibility, the limit of science and the science of limits”.
To distil, what is a complex issue, it is simply impossible to answer an ethical or moral question using the scientific method. For example, it is impossible to design an experiment to determine if slavery is right or wrong, just as it is impossible to design an experiment that shows that maximising yields is right or wrong. The problem is that it is fully within the ability of the scientific method, to design an experiment to determine how to maximise yields. This, I believe, is at the heart of much of the philosophical confusion in agriculture. We have confused a moral aim, i.e., that maximising yields is good and now consider it to be scientific.

REACH regulation

So, let us look at this issue from the perspective of a current conscious ethical debate, that of pesticides.
Europe is at present re-evaluating all ‘chemicals’ under the REACH regulation. This regulation is built on the ethical foundation of the precautionary principle, as opposed to risk assessment, i.e., chemicals need to be shown to be safe, rather than there being no evidence of their harm, put logically, absence of evidence is not evidence of absence. This has resulted in many agri-chemicals being banned, their use restricted or being removed by their manufacturers. Many agricultural scientists have been up in arms about the removal of these pesticides, based on a rational along the lines that the chemicals were created by science, are scientifically proven to be effective and there are no alternatives, so therefore to remove them is un-scientific. The other side of this debate is summed up by Professor Vyvyan Howard who said…

Professor Vyvyan Howard

“What I find most absurd is the claim that the EU proposals are not based on science. Whole teams of national and European scientific experts are involved. Where a specific pesticide is classified as being carcinogenic it's because there is substantive scientific evidence linking that substance with cancer”
So we have a situation where two groups of scientists are publically claiming their position is scientific and the other un-scientific. The problem here is not science, the problem is ethics. The two groups have quite different, and mostly un-articulated, moral frameworks, and it is these frameworks that are being disputed, but mistakenly on the scientific not the ethical battle ground.
Both positions can be viewed as an example of ‘scientism’ i.e., to claim the authority of science, where it is not valid.

Scientism and organic agriculture

Scientism has been common in regard to organic agriculture, which was often presented as being un-scientific in the 70s and 80s, and a few people still hold this view today, for example, Sir Paul Callaghan. This is nonsense. Organic agriculture uses science all the time: there are a whole swag of scientists around the world using science to study and help organics meet its ethical objectives, they even have an international society - ISOFAR, the International Society of Organic Agriculture Research.
The real conflict here is that industrial agriculture has an ethic of yield and/or profit maximisation while organic and other ecological agricultures have ethics of permanence, respect for Gaia, humans and other animals, etc., However the ethic of industrial agriculture has become for many people ‘scientific’ and thus garnered with a type of authority which it not due. Science can be used by both systems to meet their moral objectives, as science is blind to ethics, but, it can not decide which ethical system is right or wrong. That is the turf of philosophers not scientists.
However, despite being blind, science can inform ethical decisions.

Ethics consistent with reality

Using the slavery example again. While science can not decide if slavery is right or wrong, it can inform the debate, for example it can show that enslaved races have the same mental lives, thoughts, and feelings as those of the slave keepers. Had this ‘scientific fact’ been around at the time of the slavery it would have been powerful ammunition to undermine one of the key moral arguments in favour of slavery, i.e., that slaves are sub-human so it’s OK to enslave them.
Science can therefore be used to determine if the arguments used to support an ethical position are consistent with reality. Again, that’s not to say the ethic is wrong, just at odds with reality. However, having an ethic that is at sufficient odds with reality becomes a problem when the actions that result from an ethical system, conflict with the aims of the system. For example, an ethic that food supply must be increased to match current and forecast populations, when increasing the food supply without population control will result in the population expanding further, so requiring further increases in food production, ad infinitum.
If humanity, as a civilisation that now spans the entire globe, wants to be in for the long haul, I suggest that it is essential that its ethics and thus politics are consistent with reality. As humanity is still 100% dependent on agriculture, then ipso facto, agriculture also has to have an ethic that is consistent with reality. However, as I have explained, industrial agriculture is not consistent with reality over the long term, so it will not be able to provide humanity with food in the long term. We therefore have a miss-match. The solution is to change the way we do agriculture to one of permanence. That is what underpins the Future Farming Centre, a determination to create an agricultural system that can persist for as long as humanity wishes to continue .

What is agricultural science

I now want to take look at agricultural science and extension.
First I had better be clear what I mean by agricultural science. Somewhat tautologically, I take it to be science that is primarily undertaken to influence agriculture and/or farmers. I feel the need to state, what should be obvious, as there appears to be increasing amounts of agricultural science that is of no relevance to farming. To use an example from an agricultural science seminar in Ireland, when the presenter was questioned as to the use of his research for farmers, replied, “what has it got to do with them?”
I was also fortunate, while in Ireland, to attend one of the pan-European conferences titled “Towards Future Challenges of Agricultural Research in Europe” held to deliberate on the current state and future direction of agricultural science. There was an unambiguous feeling that something was rotten in the state of Demark. Not only were the presentations by the invited speakers pretty critical of the current agricultural science system, the sentiment from the audience was at times brutal.

Towards Future Challenges of Agricultural Research in Europe

One audience member pointed out that the scientific understanding of mastitis control is a line on a graph going from bottom left to top right: the control of mastitis on farms was a line going from top left to bottom right. He nearly got a standing ovation. A another person simply said that “agricultural science is broken” and practically brought the house down.
This sentiment is not confined to Europe, across the world, there appears to be a growing realisation that agricultural science is increasingly not fit for purpose.

Why agricultural science is different I

To understand some of the problems with agricultural science, it is essential to understand how and why agricultural science is different from practically every other scientific discipline.
Farmers as implementers
The first, and most important difference is that the primary users and implementers of agricultural science, are not scientists or even highly trained professionals, e.g., doctors, but mostly people with low levels of education. NZ is an exception in the high level of training among its farmers, but most still ‘only’ have a bachelors degree, not a post graduate research qualification. The scientific literature, which for most sciences, is the best way to get your research out to end users, is almost useless in agricultural science, because the people who need to know about and implement research, will almost certainly never read a single research paper in their entire lives.
Ag-science is a social science
Agricultural science is as much a ‘soft’ social science as a ‘hard’ science of physics and chemistry.
In the bad old days in the middle of the last century, when scientists as a whole were viewed as objective diviners of truth, advisory systems, were pretty linear, i.e. designed to carry information from scientists to farmers who were expected to do as they were told. It is now clear that this model does not work, we need to use the soft sciences of sociology and psychology to design research systems so that farmers and scientists can work collaboratively to ensure that the science is relevant and farmers will implement successful results, i.e., farmers and scientists need to be on the same level.

Why agricultural science is different II

This also means that agricultural scientists not only need to be experts in the science of agriculture, they also need to have a deep knowledge of real world agricultural practices. One of the key reasons agricultural science fails to be taken up by farmers, is the research is of no relevance to them because the scientist did not understand their farming systems. The blame here has to squarely lie with the scientist.
Like farmers, scientists are people, and they have value systems, morals, ethics and therefore politics. For the physicist and chemist their ethics, whether they vote right or left, has no effect on their science. However, once you start to move into the biological and especially the ecological and social arenas, a scientists world view has to have an influence on their science, often considerable, and often unconscious. Deciding to use yield as a measurement in an experiment is not objective, it is laden with a myriad ethical judgements. Measuring the amount of yield should be objective, e.g., a numerical value determined by a machine, but the values that created the decision to measure yield, mean that the results and their interpretation are not, and never can be ‘objective’. That is why every agricultural experiment, and therefore all of agricultural science is a political act.
However, I suspect that some agricultural scientists view their discipline as being closer to that of physics and chemistry i.e. they are external to their study system. In comparison sociologists acknowledge they are a part of the thing they are studying and that their world view influences how and what they research. It is perhaps time for agricultural scientists to learn from their social science colleagues and clearly state the ethical and philosophical positions that underpin and inform their research.

The Future Farming Centre I

Having touched on a few issues of agricultural science I will now highlight how they inform the way the FFC aims to operate.
First, the FFC will wear its morals and ethics on its sleeve, not under a bushel.
It will be dedicated to science for agriculture and farmers. That does not just mean research that farmers want, but also research they may not want to hear. It also does not only mean short term, production focused research. What is missing in much of current agricultural science in my view, is the big idea, long term, blue sky, whole-of-system ideas and research programs, for example, the development of no-till farming.
A strongly participatory extension system will be at the core of the FFC, to ground and inform the science, especially research aimed at solving practical farming problems, and also to ensure researchers understand real-world farming. I don't believe it is possible have an agricultural science system that does not have extension at its core, i.e. extension workers and scientists as part of the same team and sharing the same tea room. Separate advisory systems, even those in the ‘building next door’ are part of the old linear ‘scientist know best’ days, though that is still far better than the complete lack of extension systems in many developed countries.
The primary output of science at the FFC will be to farmers, with communication to scientists in second, but vital, place. This dissemination of knowledge to farmers needs to be both new science and more importantly the collation and synthesis of whole areas of existing knowledge. This is essential because the location of knowledge in industrial and permanent agricultures are quite different. This is best illustrated by pesticides: they are not only bottled chemicals, but bottled knowledge. However, for many non-chemical pest management tools there are few proprietary products or bottled knowledge: you can not put a rotation in a can, only in a brain. Therefore, permanent agriculture represents a shift in the location of knowledge from specialists, such as biochemists, to farmers. The problem is this requires farmers to learn a lot more. The advantage, as Prof. Gerry Boyle, the Director of Teagasc in Ireland, pointed out, is that such knowledge does not wear out, it can be used indefinitely at no marginal cost, which is in complete contrast to the proprietary knowledge and ongoing cost of pesticides.

The Future Farming Centre II

In terms of the range of science the FFC will undertake it will be broad in scope. Many traditional research approaches have been within production types, e.g., vegetables or dairy. Permanent and ecological agricultures often require more mixed farming and holistic approaches and they often have strong linkages between the different farm systems, so it is essential that science can also work across production types and take a whole-of-farm system based view of the situation.
Thinking holistically is great, but, often the devil is in the details, and I believe that more detailed and rigorous approaches are needed such as life cycle analysis, while understanding the limits of models and not considering them to be reality, only a guestimation.
All roads lead to the soil, and as I have outlined, it is vital that the good husbandry of the soil is always considered when undertaking research, and I also want to make it a key extension activity. As an example of this there is a growing interest among farmers, including mainstream farmers, about different approaches to soil management than the typical ‘NPK and lime’ approach, e.g., use of ‘biological’ fertilisers, the base cation saturation ratio or Albrecht approach, the soil food web etc. Some are backed by science, some lack scientific validation but may be valid, but worse some are contrary to scientific knowledge. Plus this area is beset by different ethics / objectives for soil management i.e., soil health vs yield. This is an area that clearly needs some good long term comparative experiments and thoughtful extension to tease apart the ethics from the science. It is also an area I believe farmers need truly independent advice so they do not end up buying into fruitloopery.
Research into management of nitrogen, particularly by increasing the use of nitrogen fixing species, in cropping situations, e.g., as polycultures, intercrops, cover crops etc., needs significant attention. It also probably needs some big blue sky ideas and integrated research to make such systems work in real world farming, and some solid life cycle assessment to make sure the extra nitrogen is not playing jokes on us.

The Future Farming Centre III

Linked to that is min-till. No-till is dependent on glyphosate and a very small number of other broad-spectrum systemic herbicides, that are facing significant resistance issues. We need a plan B for no till for when chemical ploughing starts to fail.
While the impacts of tillage on soil are complex and arguments fly about its relative impact on soil health compared with other issues, tillage still uses a lot of energy, so on that front alone we should be looking for new ways to minimise the amount of tillage while keeping in mind the practicalities of farming. This is especially important as more weed management moves from herbicides to physical methods such as hoeing. Again this is potentially a big can of worms, so system level thinking and analysis are going to be critical.
Most of these ideas are big, and longer term, but even though the FFC is also based on some pretty big ideas, it will also be tackling the kinds of specific issues that keep farmers up at night. For example:
I have already concluded lab tests of insect mesh covers for tomato potato psyllid (TPP, Bactericera cockerelli) management which have found them to a 100% barrier with an additional apparent disguising effect indicating they could be very effective in the field, so field experiments are in the pipeline.
Mainstream farmers are already running into resistance issues with anthelmintics, so I’m pleased to say that the FFC is a partner in a non-chemical parasite management trial with Robin McAnulty and colleagues from Lincoln Uni using their Targeted Selective Treatment (TST) system with bioactive forages. We hope to expand on this work.

The Future Farming Centre IV

The FFC is conducting a desk study on non-chemical management of phytophthora on avocados to identify existing effective methods and where new research is needed.
Another desk study is looking at the issues surrounding the potential to ferment, rather than compost domestic kitchen organic waste before returning it to the land, to help close the biogeochemical cycles, while checking for unintended effects e.g., non-CO2 greenhouse gas emissions.
There are also a lot of big and small ideas to work on in my speciality of non-chemical weed management, from better understanding of the biology and ecology of problem weeds to find their weak points, to some serious engineering in the form of intrarow soil heating to eliminate the weed seed bank in the crop row. Non-chemical weed management as a whole discipline is almost unknown among farmers, so again, this is another area that is in desperate need of extension, indeed I’ve a proposal for a comprehensive e-book waiting for funding if any funders brought their cheque books.
Therefore, there is clearly no shortage of work to be done.

The Future Farming Centre V

So, while science and extension will be the main work of the FFC, it also aspires to higher academic and intellectual goals.
The FFC will also promote the philosophy and history of agriculture and agricultural science. The history and philosophy of science (HPS) is a well established discipline, but I suspect the history and philosophy of agriculture is a new concept to many people. However, as this lecture shows, failing to understand the history and wider issues of agriculture and agricultural science, such as ethics and philosophy, can result in considerable confusion.
I also want the FFC to maintain independence from commercial and business interests as much as possible, so that it can truly offer impartial advice to farmers. Globally, organisations that used to be non-commercial have increasingly commercialised the intellectual property that they had previously given away for free, to make up for funding shortfalls. However that has often come at a loss of impartiality, both at the level of the individual, and the organisation. Farmers are finding it increasingly difficult to find impartial advice and I want to ensure the FFC is as free as of such biases as possible, and where they exist, to clearly declare such conflicts of interest.
I also see a role for the FFC as a critic and conscience of agriculture. The role of critic and conscience is normally associated with universities and in many cases it was a role that has often been hard fought for. However, as research has shown, this role has significantly declined, with academics increasingly being reluctant to speak their minds. Clearly, being an academic does not automatically make you right, but, the freedom to think hard and deep and/or conduct independent research and then freely voice ones conclusions, is a cornerstone of the enlightenment and democracies. This lecture is an example of the critic and conscience role, in that I have covered topics that may be politically and commercially unpalatable, based on my conviction that they are important and correct. Agriculture is far too important to just be left to market forces and political winds. Science, philosophy and ethics have an utterly vital roll to play as well.


So, to conclude.
Academics, have a reputation of banging on a lot, often making a mountain out of a molehill. Farmers in comparison, especially kiwi farmers, are known for being a tad more prosaic. I therefore want to give the last word to farmers.
There is a farming proverb, that sums up somewhat more succinctly, the concept of permanence in agriculture. We are increasingly overdue to start heeding its message.

Live, like you’ll die tomorrow;
Farm, like you’ll live forever.

Thank you very much.

The BHU Future Farming Centre

Mesh crop covers for, humane / non-lethal, pest control on outdoor crops
for home gardeners, lifestyle blockers and market gardeners


Left photo: Comparative yield of Moonlight potatoes grown under mesh (left) and without mesh (right) at the BHU in 2015/16.  Right photo: aphid on 0.6 mm mesh.

Please click here for prices

and to order.


See below for an extensive range of information on mesh, what it is, what it does, and how to use it.

The Future Farming Centre's Mesh crop covers for potato blight and pest control research page.

Webpage of media coverage of mesh


Commercial growers and farmers info
What are mesh crop covers?
Mesh crop covers are not Mikroclima / frost cloth
What crops can I use mesh on?
What pests can mesh control?
Tomato potato psyllid (TPP) - the original reason for research into mesh crop covers
Potato blight control with mesh crop covers: Complete control of potato pests and diseases!
Issues with aphids penetrating mesh on potatoes
Mesh and tomatoes
Customer comments
How do I use mesh crop covers?
Can I cut mesh to length / shape?
How much mesh do I need?
Does mesh give any frost protection?
General FAQ
What crops and pests are mesh crop covers less suitable for?
Why have I not heard about mesh crop covers before in New Zealand?
Other uses for mesh

Commercial growers / farmers

Iif your considering testing mesh please contact me This email address is being protected from spambots. You need JavaScript enabled to view it. 021 0231 8901 as I can probably save you a lot of time and money and happy to have a short chat at no charge. Also there is a short report  Mesh crop covers for pest control in commercial crop production that explains the history of mesh crop covers, their benefits and their current use in commercial production.

Tomato potato psyllid (TPP)

The use of mesh started in NZ as a means to control the tomato potato psyllid (TPP) on potatoes.  However, the use of mesh has now grown far beyond that, such, that some people don't know about the damage TPP can do to potato, tomato and other solanaceae crops.  Here are some links to explain the problems caused by TPP. Landcare Research factsheetPotatoes NZ TPP myths.  Plant & Food Research "Controlling the tomato/potato psyllid in the home garden"  (which oddly does not mention mesh!). 

 What are mesh crop covers?
Mesh crop covers are an organic / non-chemical means of keeping pests off crops, from as small as insects (root flies, caterpillars) to as big as vertebrates (birds, rabbits, possums, cats, dogs, deer) etc. 

They work by stopping pests getting to the crop in the first place, a bit like fly screens on a house stop the flies from getting in.  They are therefore humane as they don't kill or otherwise harm pests, unlike ‘sprays’ (even organic sprays such as neem and pyrethrum) and other chemical deterrents. 

They are very lightweight (90 grams / square meter) so are directly laid on crops without any need for support.  They were developed in the 1990s in Europe, and have proved to be so effective they are now in widely used across the EU.

Mesh crop covers are not Mikroclima / frost cloth
Mesh crop covers are also completely different to Mikroclima, which is a frost cloth and designed to keep crops warm in cold weather.  Mesh crop covers are a pest control cloth, designed to keep pests off while having little effect on under-sheet temperature so it can be used in hot weather as well as cold weather. 

What crops can I use mesh on?
Mesh crop covers can be used on just about any outdoor crop, as long as the mesh completely covers the crop down to the ground, for example, potatoes, strawberries, carrots, parsnips, cabbages, cauliflower, broccoli, kale, silverbeet, bush beans, rocket, Asian greens, lettuce, herbs, etc.  Some crops are not suitable for mesh, see the section 'What crops and pests are mesh crop covers less suitable for?' below for more info. 

What pests can mesh control?
Mesh crop covers can control a very wide range of pests, so many that it is the proverbial ‘one-stop-shop’ for insect and vertebrate pest control.  Pests that the 0.6 mm mesh available from the BHU can control includes:

  • Flea / leaf beetles  (Chrysomelidae)
  • Tomato potato psyllid (TPP) (Bactericera cockerelli) but see warning at top of page about potato aphids
  • Potato tuber moth (Phthorimaea operculella)
  • 28-spotted potato ladybird / hadda beetle (Henosepilachna vigintioctopunctata)
  • Green vegetable / shield / stink bugs  (Nezara viridula)
  • Carrot root / rust fly (Psila rosae)
  • Cabbage root fly (Delia radicum)
  • Butterflies / caterpillars, eg cabbage whites (Pieris brassicae and Pieris rapae)
  • Beetles including weevils
  • Birds - esp on strawberries
  • Wasps on grapes (this is widely used in Europe)
  • Apple and pear leaf curl midge
  • Possums
  • Rabbits
  • Cats, dogs and other domestic pets
  • Deer
  • and a wide range of other insects and vertebrates.

While mesh can control a very wide range of pests, some are more difficult to control than others.  Please see the section 'What crops and pests are mesh crop covers less suitable for?' below for more info.

Potato blight control with mesh crop covers:  Complete control of all potato pests and diseases!
Not only can mesh control pests, it can also control the fungal disease potato blight.  This is a world first, and internationally important discovery by the BHU Future Farming Centre.  Mesh is therefore an almost complete means of pest control on potatoes, i.e. it controls blight, TPP, and potato tuber moth. However, please see the warning at the top of the page about potato aphids penetrating the 0.6 mm mesh and also the proviso in section 'What crops and pests are mesh crop covers less suitable for?'.

Effect of mesh on potato blightEffect of mesh on potato blight

Effect of mesh on potato blight: green potatoes on left of photos was covered with mesh, brown potatoes with high blight levels on right of photos. Left hand photo courtesy of Scott Lawson, Lawson's Organic Farms Ltd / True Earth™, Hastings.

Customer comments
“Wondermesh” indeed.  The first time I’ve had a potato crop in years!
No more carrot fly....
It worked brilliantly on our potatoes – we waited (for the mesh) and planted late. Had a great crop.
We’ve used it to cover the brassicas too, so it is our all-purpose insect cover
I have used the Mesh now for two years and had marvelous success with my potatoes and tomatoes, as a keen home gardener who prefers to grow organic vegies I would recommend the mesh to anyone wanting natural protection for their garden.

How do I use mesh crop covers?
Mesh crop covers are a preventative pest management tool, i.e. they are not able to get rid of a pest once it is among a crop (unlike chemicals and some biological controls).  It is therefore vital that the mesh is placed on the crop before the pest arrives.  In most cases this means that the mesh should be laid as soon as the crop is planted or sown.  

If there are any pests already on transplants (e.g. caterpillars, flea beetles) they must be controlled before the mesh is put on, otherwise they can proliferate underneath the mesh, safe from predators.  

Many insect pests are only active at specific times of the year, outside of which no harm occurs to crops.  If you know when a pest is not present in your location, it is possible to leave the mesh crop covers off, until just before the pest arrives.  However, your timing must be perfect, because, as noted above, once a pest is on a crop, mesh cannot get rid of it.  

Mesh needs to be sufficiently well anchored to the soil to prevent pests sneaking underneath the edges of the mesh, and to stop the mesh being blown away.  For small areas the most effective and easy way to do this is to use house bricks and/or stones that weigh about two to three kilograms or more depending how windy your site is.  The alternative is to dig mesh in, but this requires more work.  For larger areas please see section 6.1 on page 13 of this report (PDF file) on options for anchoring mesh over larger areas. 

Can I cut mesh?

Mesh is very easy to cut to length or any shape you like with household scissors or a sharp knife. 

How much mesh do I need?
You need to have enough mesh to cover not only the width of the crop bed, but also double the height of the crop, i.e., up one side, across the top, and down the other.  Avoid trying to cover more crop than the mesh can easily cover, especially fast growing crops such as potatoes, as these will lift the mesh up, even pulling it out from under the stones / bricks holding it down.

How should I store mesh?
When you are not using your mesh on the crop it is best to store it out of direct sunlight.  This is because it is sunlight, and especially the UV in sunlight, that degrades the mesh, as it does all other plastics.  A garden shed, garage or any other dry location away from direct sunlight is ideal.

Avoid storing wet mesh as it is much heavier and any plant debris caught in the mesh is likely to rot and become unpleasant.  Mesh can be attractive to rodents as nesting material with them gnawing holes through it making it of little use.  Ensure mesh is protected from vermin during storage.

Does mesh give any frost protection?
Mesh is designed to give the minimum amount of temperature rise under the cover so that it can be used in hot summer weather without cooking crops.  It therefore offers a very limited amount of frost protection - about 1C.  In the experiments at the BHU it increased in the maximum temperature by 3°C and average temperature by an increase of 1°C.

Information on sucesses with mesh on tomatoes

The March 2017 Get Growing magazine has a great article on using mesh to grow tomatoes with exceptional results.  It looks as if concerns over pollination are not coming true and that growing your protected tomatoes under mesh is the way to a great crop. 

October 2015 NZ Gardener magazine has a another great article on the successful use of mesh for growing tomatoes.  I have also had a number of customers contact me also reporting that they have had excellent crops of tomatoes, even their best crops, using mesh.  There is also research from Israel, where they use mesh instead of plastic sheet on their polytunnels, that mesh is reducing tomato blight in experiments, the same as it reduces potato blight in our experiments.

Information about potato aphids penetrating 0.6 mm mesh.

In the 2016-17 field trial we have consistently found aphids penetrating mesh.  We now believe that the winged adults are landing on the mesh and then smelling / tasting the potatoes so they don't fly away and then produce nymphs (babies) which are small and soft enough to get through the mesh.  Once inside and protected from natural predators they can multiply to problem levels.  The recommended solution that commercial organic growers are doing is to leave one edge or end of the sheet open so if aphids do get in the predators can get in also.  If you do get an aphid outbreak then it is best to take the cover off for a couple of days and then put it back on, thus trapping some predators under the mesh with the aphids.  Leaving the mesh off for a couple of days wont allow many TPP in, and, we have shown that due to the UV light blocking effect of mesh, TPP don't like it under the mesh, so unlike aphids, if you do get a few TPP underneath, they wont cause much damage, unlike the aphids.  It is still a good idea though to avoid having any plants that host potato aphids growing on the outside of mesh, to avoid a green bridge. 

Mesh is still just as effective at controlling all the other pests listed on this page.

General FAQ
How long do mesh crop covers last?  The mesh has  three year guarantee, but, in Europe commerical growers get up to 15 years out of sheets, so you can expect mesh to last at least a decade in NZ. 
Can rain get through the mesh and can I water / irrigate through it?  Yes, rain and water just go straight through the mesh, and as it improves the micro-climate crops may need less water.
Can I apply liquid feeds and fungicides through the mesh?  Yes, any water based material such as liquid fertilisers / feeds and fungicides can be applied through the mesh.  
How much sunlight gets through the mesh?  Mesh allows about 85% of sunlight to penetrate, and as sunlight is generally not the limiting factor for plant growth in NZ, an approx 15% reduction in light levels is unlikely to have any negative impact on the crop.  Water and nutrients are most likely to be the limiting factor for crop growth. 
What effect does mesh have on wind among the crop and ventilation?  Mesh provides about a 25% reduction in wind blowing through the crop, which can provide a significant improvement in crop microclimate through reduced wind buffeting, while mesh is sufficiently porous that it ventilates freely and therefore has negligible effect on under-sheet humidity. 

What crops and pests are mesh crop covers less suitable for?
While mesh is very versatile, it is not miraculous, and there are some pests and crops that it is less effective at controlling or less suitable for. 

Mesh will keep out large aphid speices, such as cabbage aphids, but, the 0.6 mm mesh we are selling will not keep out the juvenile forms of small aphids such as potato aphids.  Also as aphids reproduce asexually (vivipary) and also very rapidly, it only takes one aphid to get under the mesh to result in an outbreak.  If you are going to use mesh for control of large aphid speices it is vital to ensure it is well sealed to the soil / ground, e.g. with lots of bricks or rocks.  Conversely, if you do get aphids under the mesh, you need to created a gap around the edge of the mesh to allow beneficial insects such as ladybirds, hoverflies, and parasitoid wasps to get under the mesh to control the aphids. Also to minimise the chance of juvenile aphids getting through the mesh avoid having a ‘green bridge’ i.e., having plants growing against the outside of the mesh. 

If you do have problems with aphids it is also possible to introduce biological control agents under the mesh to control them, the same as is done in polytunnels and glasshouses.  Ladybirds are good aphid predators and will also eat other pests as well.  You can either collect your own ladybirds to put under the mesh and there are also commercial suppliers such as BioForce that supply them.  This is neither an endorsement of BioForce nor is the non-inclusion of other suppliers a non-endorsement of that supplier.  

Very tall crops, i.e. sweetcorn, are a bit more challenging, especially as they are also very fast growing.  Options include using two pieces of mesh, side by side to ensure the crop is fully covered.  See also the section ‘How much mesh do I need’.  It is also difficult to put mesh directly on supported crops, such as climbing / indeterminate tomatoes.  However, we are getting increasing numbers of reports (including the published articles listed at the top of this page) where people have been using mesh on tomatoes using large cloches or building frames or even using it on tunnel frames and have been getting excellent, even their best, crops of tomatoes.  This may be due to the blight inhibiting effect of mesh and also the improved microclimate.  Mesh is also being used on vines to keep wasps off the grapes. 

Most crops are sufficiently strong to be able to directly support the mesh, even from seedling stage, however, a few are not strong enough, e.g. young leeks, in which case, the mesh can be used with a cloche system, or any means of supporting the mesh above the crop until the crop is strong enough to support the mesh by itself. 

Some crops require insect pollination, especially by honey bees, and mesh covers are as effective at keeping pollinators out as pests!  In such cases it will be necessary to take the mesh off when the crop requires pollination or use an alternative means of pollination. This is apparently not the case with tomatoes as increasing numbers of people are growing tomatoes inside mesh cages / tunnels and getting excellent results, even the best crops they have ever had.  There may well be sufficient wind and other physical movement of the plants to ensure pollination. 

Why have I not heard about mesh crop covers before in New Zealand?
The use of mesh crop covers in NZ was pioneered by the BHU Future Farming Centre for organic / non-chemical control of Tomato Potato Psyllid (TPP) on potatoes. Mesh manufactures are now selling mesh in NZ, however, importers are only selling commercial quantities (hectares) to farmers and growers, so the BHU is selling mesh of a suitable size (square meters) as a service to home gardeners, lifestyle blockers and market gardeners. 

If you have any other questions please email Merf at This email address is being protected from spambots. You need JavaScript enabled to view it.


Newly emerged potatoes

Potatoes after ridging up

Mature potatoes




Other uses for mesh

We have a growing list of other uses people are finding for mesh, including hand made paper frames and whitebait nets.  Mesh is now being used to make wallets from banana trees - see the YouTube video.  Let us know any other novel uses you have for mesh!

The BHU Future Farming Centre

Your mesh crop cover order is complete!

Thank you very much for your mesh crop cover order.  

You will also of been automatically emailed a copy of your order.  If you do not receive such an email within an hour, please email This email address is being protected from spambots. You need JavaScript enabled to view it. and we will check to see what the problem is. 

We normally download the weeks orders from this website on Wednesdays and then send out invoices, so if you don't have an invoice by the Wednesday evening following placing your order, please email This email address is being protected from spambots. You need JavaScript enabled to view it. so we can follow up.  Payments that are received by the following Monday morning will be dispatched Monday or Tuesday morning. 

Return to:

BHU home page

FFC homepage

Mesh information page

The BHU Future Farming Centre

Mesh crop covers order form - all profit from your mesh purchase goes to further our charitable goals.

Please note we are not a shop.  If you come to the BHU without prior arrangement there may be no one here.  To purchase mesh please order through the form below and then arrange a pickup time.

Commercial growers / farmers - if your considering testing mesh please contact me This email address is being protected from spambots. You need JavaScript enabled to view it. 021 0231 8901 as I can probably save you a lot of time and money and I am happy to have a short chat at no charge. 

Please read the information below on the price of mesh and the cost of delivery, and then fill in the form at the bottom of the page. 

The BHU is selling mesh as a service to home gardeners, lifestyle blockers and market gardeners, i.e. it is a side line to our normal business of science and education.  We therefore only have basic systems for handling sales, so we ask for your patience.  

Once you have submitted your order, an automatic confirmation email will be sent so you know your order has been recorded by the website, if you dont get this email within an hour of placing your order please email This email address is being protected from spambots. You need JavaScript enabled to view it. and we will check what went wrong.  The main issues we have are incorrect emails - please double check your email is correct.  Once a week, normally, on Wednesday morning, we email out invoices for orders received that week.   Payment is required prior to delivery: we accept cash, cheques or online bank transfers as payment, N.B. we do not take credit cards, as we are not a shop.  We normally pack on Mondays: payments that are received by 9:00 am Monday, are packed and couriered on Tuesday morning, with delivery varying from next day for Christchurch and surrounds to about three days for North Island, i.e., by the end of the week.  If your order is exceptionally urgent, please email This email address is being protected from spambots. You need JavaScript enabled to view it. and we will try to process your order ASAP but we cannot guarantee this.

Mesh pricing

The mesh is Cosio 'CROPSAFE NET' with a 0.6mm hole size and a width of 3.7 metres.

 Mesh is sold in standard lengths of 5, 10, 20, and 50 metres.  If you want multiple smaller pieces, eg two 10 m lengths mesh can be cut very easily with household scissors so pls order just one length.  Prices are:

Length  Width Area m2  Price incl. GST
5 metres 3.7 meters 18.5  $52.00
10 metres 3.7 meters  37.0  $96.00
20 metres 3.7 meters  74.0  $185.00
50 metres 3.7 meters 185.0 $415.00
100 metres 3.7 meters 370.0 $830.00
150 metres 3.7 meters 555.0 $1,245.00
200 metres 3.7 meters 740.0 $1,660.00

If you want to purchase more than 50 metres the form below allows purchases of up to four rolls.  If you want to order more than four rolls please email This email address is being protected from spambots. You need JavaScript enabled to view it. . The total price for multiple lots of 50 meter rolls is the single roll price times the number of rolls. This is because each roll is the maximum size/weight the courier will deliver and the 50 m roll is already discounted so there is no extra discount for ordering multiple rolls. 

Delivery costs

Delivery is via courier or pickup from the BHU at Lincoln, Canterbury (see our contact page for map location). Pickup from the BHU is free! (but see the note at the top of the page about the BHU not being a shop and not calling without and appointment). Courier delivery is divided into three areas:  'Canterbury' (i.e. local), rest of South Island and North Island.
Canterbury is defined according to Fastway Couriers (see this Fastway PDF info sheet for details (N.B. prices listed are ex. GST)) and includes everything from Kaikoura as the northern limit, through Hanmer Springs, Craigieburn, Lake Coleridge, Geraldine and Timaru as the southern limit, and everything to the east of them.  We will confirm your delivery area when we process your order. Our / Fastways decision on your delivery area and cost is final. If you are not happy with that decision you are welcome to cancel the order. Rural deliveries, i.e., with an RD address have a extra charge, regardless if your area is Canterbury, rest of South Island or North Island. Delivery costs are as follows, all are GST inclusive:

Length meters Pickup Canterbury Canterbury RD S Island S Island RD N Island N Island RD
5 meters $0.00 $11.43 $17.24 $15.86 $21.67 $16.70 $22.51
10 meters $0.00 $11.43 $17.24 $15.86 $21.67 $26.99 $32.80
20 meters $0.00 $11.43 $17.24 $15.86 $21.67 $26.99 $32.80
50 meters $0.00 $26.52 $32.33 $46.03 $51.84 $57.17 $62.97
Two 50 m rolls (100 m) $0.00 $53.04 $64.65 $92.07 $103.68 $114.33 $125.95
Three 50 m rolls (150 m) $0.00 $79.56 $96.98 $138.10 $155.53 $171.50 $188.92
Four 50 m rolls (200 m) $0.00 $106.08 $129.31 $184.14 $207.37 $228.67 $251.90


Total Cost 

The combined / total cost of mesh and delivery, inc. GST (i.e., the total amount you will pay) is: 

Length meters Pickup Canterbury Canterbury RD S Island S Island RD N Island N Island RD
5 meters  $52.00 $63.43 $69.24 $67.86 $73.67 $68.70 $74.51
10 meters $96.00 $107.43 $113.24 $111.86 $117.67 $122.99 $128.80
20 meters $185.00 $196.43 $202.24 $200.86 $206.67 $211.99 $217.80
50 meters $415.00 $441.52 $447.33 $461.03 $466.84

$472.17 $477.97
Two 50 m rolls (100 m) $830.00 $883.04 $894.65 $922.07 $933.68 $944.33 $955.95
Three 50 m rolls (150 m) $1,245.00 $1,324.56 $1,341.98 $1,383.10 $1,400.53 $1,416.50 $1,433.92
Four 50 m rolls (200 m) $1,660.00 $1,766.08 $1,789.31 $1,844.14 $1,867.37 $1,888.67 $1,911.90

Ordering Form

As we are selling mesh as a service to NZ gardeners and small growers that is outside the normal educational and research activities of the BHU (i.e. we are not a regular shop), most of the ordering and invoicing system is manual.  We normally download the weeks orders and send out invoices on Wednesday morning.  If you dont receive an invoice by Wednesday evening please email This email address is being protected from spambots. You need JavaScript enabled to view it. so we can follow up.  Payments that are received by the following Monday morning will be dispatched Monday, or Tuesday morning.  It may therefore take a week or two between placing an order and receiving your mesh.  If your order is truly urgent please email This email address is being protected from spambots. You need JavaScript enabled to view it. to let us know and we will try and be accommodating. We guarantee your privacy: We will never sell, rent, or give away your details to any outside party, ever.  Please see our Privacy Policy for full details. Fields marked with an '*' are required.  We need a physical delivery address for the mesh, a PO Box is not suitable. We also need your full phone number including area code for the courier, and also in case there is a problem with your email. We will communicate by email, unless there is an urgent or complex problem in which case we may need to phone you. Please indicate your delivery location as well as your address details as this helps us a lot.  Please make sure if you are an RD delivery you select an RD delivery location. If you have any other questions or problems with the form please email This email address is being protected from spambots. You need JavaScript enabled to view it. . Please note the security CAPTCHA at the bottom is case sensitive, and if you don't enter it correctly the form will reset - sorry we cant fix that. 

Length of mesh required *
Delivery location *


The BHU Future Farming Centre

Information - Miscellaneous

Alternatives to tanalised wood posts

Disclaimer, copyright and licensing

Quick links:  OANZ ‘Over The Fencepost’ booklet.  BHU non-CCA post demonstration vineyard.  

Tanalised/ copper chromium arsenate (CCA) treatment is the almost exclusive preservative treatment for soil contacting and exterior wood especially for pine (excluding that used for building construction), in New Zealand.  Typical examples include livestock fence posts, and perennial crop (vines and tree) trellis / support systems.  

However, there is growing concern, both within New Zealand and internationally, about problems with ‘tanalised’ / Copper Chromium Arsenate (CCA) treated wood.  These include the use of heavy metals as a preservative, the potential for them to leach into the soil and wider environment, especially in production systems with high concentrations of posts, e.g. vineyards, the health effects on people contacting the posts, e.g. fencing workers and children in playgrounds, and with the disposal of treated timber at the end of its life (landfill being the only current safe option).  Due to these concerns, organic agricultural production standards, both in NZ and overseas, have or are banning the use of CCA, and similar wood treatments.  

Farmers and growers are therefore increasingly interested in using, or are being required to use, alternatives to CCA treated wood.  

As part of the response to the banning of CCA wood in organic production standards, in 2010 OANZ (Organics Aotearoa New Zealand) undertook an analysis of the alternatives to CCA treated wood posts and published the results as the “Over The Fencepost Alternatives to CCA (Copper Chromium Arsenate) treated wood”.  This document is provided by the FFC for general information purposes as a number of the posts / manufacturers listed in the report are no longer available, and there are also new posts / manufacturers that are not listed.  You are recommended to check other sources of information, e.g. adverts in the trade press / the web, for other potential posts and suppliers.  

BHU non-CCA post demonstration vineyard

At the time the OANZ ‘Over the Fencepost’ report was published, a grape cultivar / variety genetic library was being established at the BHU. The opportunity was taken to use non-CCA posts in the vineyard as a demonstration project.  

The following posts were used in the vineyard.

Post name Manufacturer / supplier / website link
UltraPost Industrial Tube Manufacturing Co Ltd
EcoPost Industrial Tube Manufacturing Co Ltd
Wood Shield Wood Shield Pty
Eco Trellis NZ Tube Mills
IR posts Integrated Recycling Ltd (AU) / Pukekohe Timber & Packaging (NZ)
Recycled Plastic Post Empak Distribution
Wallaba Posts BBS Timber

The post collection is a demonstration rather than a trial, so no comparisons are being made among the different posts.  Also inclusion of any particular post is not an endorsement of that post by the BHU or FFC nor is the non-inclusion of any post a rejection of that post by the BHU or FFC. 

However, anyone is welcome to view and assess the posts for themselves during normal working hours.  The vineyard is sited at The BHU Farm, The Hort Research Area, Lincoln University.  Google map. You can also email This email address is being protected from spambots. You need JavaScript enabled to view it. for more information.