In practice it has never been remotely that easy and these days there are some new and very difficult challenges. As soon as you prepare any land for growing then lots of things that you didn't plant will fight to use the space to grow and plenty of different forms of life will try and eat the seed that you've planted, the young shoots as they grow or the mature plant a few days before you get round to harvesting it. There is competition to grown and eat which has to be dealt with.
For the vast majority of human existence we have managed by the skin of our teeth to just about fight off enough of that competition to get more energy back from the land than we put into it. Agriculture usually produced a surplus. Sometimes a very promising surplus that could be stored against hard times and sometimes a desperately thin one that left a significant chunk of humanity battling against famine. It did, however, take the vast majority of human effort to prepare the land, tend the crops and harvest, process and store the produce from it. Very few people did anything else other than farm and food production.
All that has now changed. And of course that is very much for the good. But on a historical scale the changes have been rapid and dramatic and we still don't know the full implications of this radical change in human lifestyles and the even more dramatic increases in human population it has made possible. Put simply we have altered every stage of the food production process and at every one of those stages we have introduced new risks that we don't yet fully understand.
It starts with the soil. Mechanisation has made it possible to clear a lot more land and to plough it deeper. That means that very much more land has entered into agricultural production and so there is a lot more human food around and a lot less for wildlife. There is also a lot less forest and a lot more areas where the limited supply of productive soil is washing away for once and for all. In order to keep that soil fertile huge quantities of fertilizer have been dug up or produced and applied to the soil. Which has increased productivity enormously. It has also dangerously depleted the limited stocks of potash available on the planet and resulted in the pollution of rivers, ponds and oceans by the run-off from agricultural fertilizer.
Then we hit problems over pesticides. It is easier for mass production agriculture to grow one crop across a large area of land so that machines can run easily and therefore economically over long distances. Unfortunately that means that it is also easy for pests to attack that crop. If you have a little bit of one crop and a little bit of another and a rotation of what you grow then pest levels are naturally lower and predators can usually see off enough of them to leave you with a decent crop. If you have one thing growing across over a mile of land then the things that like to eat that crop are going to find it in very large numbers and will devastate that crop unless you take action.
For around a century now the answer to that difficulty has been to spray the crops with pesticides, often with several different ones at different stages in the growing cycle. Which works very well on one level and has been one of the prime reasons why so many people are able to eat well on a crowded planet. Unfortunately it is far from clear that this solution can be sustained over decades or what the consequences will be for the long term health of the planet.
One of the first really effective pesticides that was applied was DDT. At first it seemed a wonder solution as it increased production enormously. Then it was noticed that it killed birds, bees and predators as well as pests and several of the worst pests evolved to be immune to its worst effects. It was still being heavily used in China relatively recently and as a result there are huge areas of land where fruit has to be pollinated by hand because there still aren't any living bees.
The pesticide companies moved on and produced new pesticides that carried fewer risks and had more precise targets. Indeed they got so clever that they put the pesticide directly into the seed so that it penetrated the whole plant but never touched anything else. What could possibly go wrong? Well actually what went wrong with these neonicitinoid poisons is now becoming clearer by the week. The pesticides get into the soil via the plant and then washes into hedgerows where some independent studies have found higher concentrations than from spraying. The pesticides weaken the navigation systems of bees and damage the strength of hives. So that French sunflower farmers found that the number of surviving bee hives was going down strongly. Eventually, under pressure from French farmers and beekeepers who had seen the damage first hand, the EU introduced a partial ban of some of these new pesticides. The UK government, under the influence of large industrial UK farmers did everything it could to weaken and remove this ban. As it was doing so the evidence mounted steadily that bumble bees were being weakened and killed by these products and that the chemicals remained in the soil for up to a decade causing unknown damage to the billions of little studied organisms that live in the soil and are vital to agriculture.
We are now at the point where virtually every single type of mass use pesticide that is available has been shown to do damage to the environment and is becoming less effective because the pests are becoming resistant. Once that effectiveness goes it becomes extremely difficult to grow things via mass production methods because so many natural predators have been killed off. There simply aren't as many predatory insects, birds or bats around as there used to be in any part of the world where industrialised agriculture has been practiced for any length of time.
But even that isn't the end of it. Much of what is grown is grown by use of machinery and that machinery is oil powered. Do the maths on the calories put in to grow something and the calories we get out after it is grown and you end up with some very scary calculations. Many crops are actually grown in ways that means agriculture is actually producing a regular calorific loss. Fossils fuels may be cheap but they contain a lot of stored sunlight from millions of years ago. Burn them, produce fertilizers in a factory, produce pesticides in another one, transport those products, drive your tractor across the ground and then take your food to the supermarket and get it collected by a car driver and you have a very negative calorific value. We are living off borrowed energy and farming fossils not farming in balance with the environment.
This is obviously not a sustainable situation. The chemical companies are looking to solve this by genetically engineering improved crops and by making increasingly clever pesticides. It is entirely possible that this will result in responsible objective scientists producing a wonderful series of inventions that will help us escape from the impossibility of continuing to farm in ways that produce less energy than they require. It is also entirely possible that the employers of these scientists will only pay for research that produces the answers they want and that once again chemical companies will tell us they have found a gloriously easy quick fix. Only for us to find that it will provide us with even worse problems in the long run.
I think we need to plan now for a serious effort to get agriculture back into balance with the environment. I am not arguing for everything to be produced organically because it is not yet possible to grow every crop by organic methods and still succeed in feeding the planet. It is, however, completely possible to start changing the way we produce and consume to ensure that it matches the seasons better and make sure that much larger amounts of UK food production is done by planting smaller areas of a greater variety of crops in any one farm and using a lot more crop rotation. Internationally it is also thoroughly possible to move away from giant industrial palm oil plantations or idiotic schemes to mass produce biofuel. Forrests that have been cut down to grow these damaging crops can be turned into varied orchards containing a mixture of highly productive nut and fruit trees and generate more income and more security for countries with a high level of dependence on agricultural production. This kind of agriculture won't replace the rain forest but it will protect the soil and provide a much wider variety of habitats for wildlife.
We therefore need to redirect any UK aid money so that it only helps foster sustainable long term agricultural methods. At home we need to do exactly the same with agricultural subsidies. If the UK has to be out of the EU then we need to make sure that we radically redirect taxpayers' money into smaller farms to help them adapt to more sustainable ways of producing food. If we remain in the organisation then we need to see EU farming subsidies moved away from giving free money to wealthy landowners to mass produce chemical soaked crops. A lot of land in the UK can't be farmed without subsidies from the taxpayer. The public therefore has a right to ask that its taxes are only used to pay for looking after land properly and not wasted on gifts to very large landowners. We need to be paying for improved practices and sustainable approaches and gradually moving away from high risk energy negative farming.
The risks generated by highly vulnerable large scale agriculture are going to be one of the key challenges of the next few decades. I believe that they represent an even bigger challenge than climate change. Most people have at least heard about that challenge and understand something of what needs to be done. Very few people have even begun to worry about the full extent of the risks associated with industrial agriculture. It is time we started to become more aware of those risks and to change UK farming policies to start to tackle them.