Science, farming and fossil fuels: An organic crop researcher talks about the science of farming

Dr. Charles Merfield, or �Merf� as the approachable New Zealander prefers to be called, is making waves across the Irish agricultural landscape at the moment. Merf works for Teagasc (Irish state's agri-advisory and research organisation) as an organic crop researcher, and is based in Johnstown Castle, Wexford, Ireland. Merf's own site, which carries info on his research, letters published in the farming press etc is here

Oliver Moore: First thing first Merf, tell me a little bit about yourself and your background - hw did a New Zealander end up as a researcher in Ireland?

Merf: My partner is a soil microbiologist and nitrogen specialist and was working for Teagasc in 2006 - I heard about the job when I came to visit her. It�s also the only job in organic cropping research I found in the EU - something I find rather odd considering the general enthusiasm for organics at the moment, so I am very glad I got the position.

Oliver Moore: Do you have any practical experience in farming?

My background is in commercial horticulture - I studied at Writtle College in the UK. I then had jobs managing organic horticultural farms in the UK and New Zealand. This has given me a really solid grounding in real farming and business - which I feel is an invaluable asset now I am mostly on the research side of the fence. I only have to think back to standing in a cold wet field harvesting vegetables to remind myself of farmer�s priorities. I find agricultural scientists that have come from purely academic backgrounds without farm experience are missing something, and ag science is poorer as a result.

Oliver Moore: Your perspective on where agriculture is going has been attracting a lot of attention recently, in both the farming press and at various agricultural events. Firstly, can you give me a brief historical perspective.

Merf: Since the beginning of agriculture until the enlightenment and the industrial revolution, agriculture has been firmly embedded in the carrying capacity of the local ecosystem in which it operated. Human history in that time is riddled with endless examples of human societies that exceeded the ecological carrying capacity of the land, thereby destroying it and themselves. This is a key theme in Tim Flannery�s �The Future Eaters�. Indeed it is difficult to think of any large civilisation that has not destroyed its resource base and therefore itself. One exception held up in organic circles are the ancient Chinese who farmed the same lands for millennia without loss of fertility or productivity, due to the constant recycling of all nutrients from animal, including human, manures back to the land.

For me there are two key changes that fundamentally altered this situation - science and fossil fuels. Fossil fuels are not just fuel but are the �feed stock� for most of the materials on which our modern lives depend. Anything you see around you that you cannot clearly see is made from biological material, for example a solid wood table, is almost certainly made �from� fossil fuel, mainly oil. Unfortunately practically everything in the modern world is made �with� oil or other fossil energy, even if it is of biological origin and not made �from� oil. In other words, the energy from fossil fuel was used in its manufacture. Fossil fuel therefore provides nearly all of the energy and �feed stock� for the modem world, materials that were previously provided almost exclusively by agriculture. I therefore think the term �fossil land� is a far more accurate and useful term than fossil fuel.

Oliver Moore: So what�s the problem with fossil fuel or fossil land dependence then?

Merf: Peak oil is the problem. Fossil fuels having been in common use for about 300 years, nearly eight generations. Fossil fuels are so �normal� that most people cannot, or maybe until the last couple of years, could not conceive that they would not last for ever. However, its very basic maths that if you have a finite resource and progressively use it up then at some stage you will of used half of it up, that is, peak supply, at some time use all of it up, and at some point in-between its scarcity will drive its cost so high it will in effect preclude its use for most purposes. Once it is gone, it is gone forever - at least in geological time scales.

From my perspective science and fossil land make an unholy alliance. Without fossil fuels, science and technology would have been forced to work within the ecological carrying capacity of the land, and when they tried to exceed it they would be been utterly rebuffed. The carrying capacity of land is no different to the productivity of a cow, say. You can�t keep milking a cow without feeding it and expect to get milk forever, but that is often the belief about ecosystems: you can�t milk an ecosystem forever without feeding it, i.e., replacing that which you remove from it, and expect it to last forever. Had there not been fossil fuel and society had hit the ecological wall, after a few crashes �science� should have figured out what was going on and figured out how to stay within the ecological carrying capacity.

However, modernity has effectively ignored the carrying capacity of its ecosystems by consuming fossil land, in the form of oil and coal. These replaced the nutrients and energy that had previously been produced by agriculture. I hope the term �consuming fossil land� or just �consuming land� gives some insight into how insane this is. No farmer in his right mind would allow the destruction of part of his or her fields with each harvest, but this is what we are in effect doing when we consume fossil fuels, that is, fossil land. Both land and fossil fuels are finite resources and if we destroy them it takes a very long time, millennia for soil, tens of millions of year for fossil fuels, to replace them.

We have therefore used fossil land to both boost our current agricultural land area, increasing its productivity while also directly using fossil land to feed, clothe and house ourselves. Indeed, there has been so much fossil land available we have used it to have one �huge consumerist party� that far exceeds what our agricultural land would of supported on its own.

Oliver Moore: Give me a specific example, Merf

Merf: A key example using fossil land to directly boost the effective agricultural land area is nitrogen fertilisers. These are made from and with the natural gas methane, mostly as the feed sock / raw material but about 10% or so as the energy source to drive the Haber�Bosch process. By applying N fertilisers we can increase crop yield, which in the case of pasture, means we can increase stocking density. However, this is an illusion. If a farm had to produce all of the methane and energy required to produce the nitrogen fertiliser it uses then its stocking rate would be far lower, due to the land area needed. I have yet to see an analysis of this but I bet that it would be possible to get a far higher stocking rate using legumes to produce the nitrogen than the Haber�Bosch process using farm produced methane and energy.

Oliver Moore: What does this kind of analysis mean for society�s ability to feed itself?

Merf: We need ten times the amount of agricultural land we have in Europe to supply our current energy needs. On top of this about 15% of oil is used as �feed stock� to make plastic and all the other materials we have substituted for biological materials such as wool, cotton, wood and so on. So at a rough estimate we may need 15 times our existing agricultural land area to meet our current energy and synthetic material consumption, oh and one existing land area to produce our food, plus half as much again if it�s to be done within ecological constraints. Even if the figures I use are out by a power of ten we are still in serious trouble.

Oliver Moore: In the short term, what will this mean for agriculture in Ireland?

There will come a point when rotations will have to come back into mainstream farming, as clover will prove to be a cheaper source of nitrogen that the current oil-based sources.

Poultry, as a non-ruminant, needs quite a considerable quantity of grain to perform. Free-range poultry can be fed on some grass, but not completely on grass. The same goes for pigs. Now, they can be fed on various fodder crops, but you won�t get the growth rates.

In organics, the two organic meat products that cost far higher for the consumer are pigs and poultry, because organic producers can�t substitute pasture in for grain. Organic beef has the lowest price premium, especially in places like Ireland where the production differences are small.

The pig and poultry producers just don�t have the same sorts of pasture options. Their animals are indoors all the time and fed highly concentrated, high energy rations. But the whole system is based on cheep feed.

The dairy guys can look at places like New Zealand, which has similarities to Ireland, and see how to maximise the use of grass. The obvious easy one is to start to introduce clover. Clover increases quality, digestibility, protein, you get free nitrogen fixation - it�s a puzzle as to why more non-organic farmers aren�t doing it!