Arable is the biggie. It produces most (or almost all) of the “staple” crops which provide us with most of our “macronutrients”: protein, and food energy in the form of carbohydrates and fats (which include the oils produced by oilseeds such as rapeseed (American “canola”), sunflower, and soya).

Chief of the staples are the big-seeded grasses (family Poaceae) known as cereals, of which the main ones are wheat, rice, and maize (which the Americans call “corn”); then barley, oats, rye, triticale, sorghum, and millet. Wheat, rice, and maize between them provide humanity with about half our food energy and (surprisingly!) more than half of our protein. Also important are the big-seeded legumes (family Fabaceae, formerly called Leguminosae) known as pulses. They include peas, lentils, and beans of various genera including Vicia (broad beans etc), Phaseolus (kidney beans) and Glycine soya (which is a huge source of protein but is officially classed as an oilseed). Third in importance are root and stem tubers, of which the main one is Solanum tuberosum, the potato. Finally, there’s a range of non-cereal seeds which are important staples in some cultures and are also sold as exotics in rich countries, including buckwheat (of the dock family, Polygonaceae), quinoa and amaranth (both now placed in the family Amaranthaceae).

The term “arable” derives from the Latin for “ear”, as in ear of corn (in the English sense: commonly applied to wheat and often applied to other temperate cereals). In practice, though, the term is now applied to all annual (or sometimes biennial) crops that are grown on the field scale. The soil traditionally is ploughed and harrowed, and the seed is sown en masse, either broadcast on the surface or “drilled” in rows. Nowadays, then, a great many crops that traditionally belonged to horticulture are grown on the grand, arable scale, including carrots and leafy brassicas of all kinds (cabbages, broccoli, etc).

A great and growing proportion of soybean and cereals are side-tracked as feed for livestock – meaning that a large and growing proportion of livestock is a by-product of arable farming. Nowadays, too, cereals are grown specifically to be burnt as “biofuel” or to be fed into anaerobic digesters. Cereals have always supplied a range of other useful by-products including straw, which on mixed farms is a huge resource for bedding and to some extent for feed, and in both cases winds up as manure, which ideally then is composted, adding much-needed organic carbon to the soil; and arable farmers also produce a range of non-food plants such as hemp. For all these reasons alone, then, arable really is the biggie.

But it’s the biggie too for another reason. Of all forms of farming, arable lends itself most readily to mechanization and hence to industrialization; which over the past 100 years has come also to include massive inputs of industrial chemistry – fertilizers, herbicides, and pesticides of many kinds. The modern vogue for biotech, manifest mainly in GMOs, is in practice an extension of the industrial chemical industry. Mechanization and industrial chemistry are most economical, per unit of food produced, when they are scaled up – so big-time commerce and governments like Britain’s encourage arable farms to grow bigger and bigger. These days arable farms in Britain commonly run to several thousand hectares. In the Ukraine there are arable units of 300,000 hectares and more – far bigger than most English counties. In the Cerrado, the dry forest of Brazil, arable farms and plantations of sugar-cane may be hundreds of square kilometres, and each square km is 100 ha.

On such a scale, the price of land becomes very significant; and the land that is most suitable for large-scale arable – in particular, big machines are at their best on the flat-lands left behind by long-receded seas – is at a premium. Land that was too wet for arable farming has been conscientiously drained the world over these past few centuries, and the peat that it often leaves behind helps to create beautifully cultivable soil – though this, if not constantly replenished, is eroded by oxidation or run-off. Contrariwise, huge areas of arable land are irrigated. What with the price of land, the huge specialist machines, the industrial chemistry, and the drainage and irrigation, the capital invested in today’s industrial arable is vast. (I don’t know if the total investment in arable has ever been calculated. Perhaps someone would care to comment?) The nature of the neoliberal economy is such that capital tends to be concentrated in fewer and fewer hands. So the richest arable farmers or landowners tend to become richer and richer, and in the modern economy, as much as in the feudal past, the hugely rich call the shots. One way or another, then, there is enormous commercial and political pressure to make arable farms more industrial, and bigger and bigger.

In this as in all things there are pros and cons. On the plus side, industrial arable farming is enormously productive. In Britain in 2015 arable yields averaged a record 9.1 tonnes per hectare. One field in Lincolnshire yielded a world record 16.5 tonnes of winter wheat per hectare, which is truly astonishing. A hundred years ago, farmers were generally well content with 2.5–3 tonnes per ha (about one ton per acre), and on traditional farms in less favoured areas in much of the world today, with traditional varieties, one-and-a-bit tonnes per hectare is still a reasonable average. It isn’t surprising that so many politicians and others in high places truly believe that the future of agriculture lies in ever-increasing arable yields, and hence in the technologies that make this possible, and the scale-up that seems to make it affordable. (Though the farmer who produced the 16.5 tonnes yield did so only to prove that this is possible, and has emphasized that he intends in future to focus on resilience).

Yet large-scale industrial arable has huge downsides too. Farming that relies on big machines and on huge inputs of chemicals, which must be applied with the help of more big machines, has to be simple. Big machines can do wonderfully complicated things (as modern combine harvesters do) but they prefer to deal with one crop at a time. Indeed, big-scale arable farming leads us to large-scale monoculture; one crop at a time over the biggest possible area, with each crop as uniform as possible. But agroecology, the approach that can truly serve the needs of humankind and the biosphere far into the future, demands diversity. Monoculture with genetic uniformity flouts its principles absolutely.

Furthermore, the more uniform the crop and the bigger the scale, the more vulnerable it is to pests and diseases – and the more, therefore, it needs the protection of agrochemistry, albeit abetted these days by GM. It’s a vicious cycle.

Such huge inputs and such vigorous application, with bigger and bigger machines, is not sustainable. Soils are compacted by the heavy machinery and precious soil carbon is not adequately replaced. Degradation of soil worldwide is now a huge and growing problem. The inputs, too, are unsustainable. As things stand, the agrochemicals and the machines are entirely oil-dependent, and oil as everyone knows is a finite resource. Besides, the more we burn up fossil fuels the more we wreck the climate. All farming nowadays, but particularly arable, supplements rainfall with water from rivers, lakes, and aquifers and all are finite, or slow to replenish, and highly vulnerable. Everyone suffers or is liable to suffer when fresh water is lacking. The chemicals, too, don’t all stay on the fields they are meant to protect and “improve” but infiltrate the whole biosphere up to the poles and down to the deepest oceans in frightening amounts (although a little is often enough to wreck an ecosystem).

Furthermore, the industrialization of farming and particularly of arable spectacularly reduces the need for hands-on labour. Those who advocate the industrial approach (who include most of the richest and most influential people in agriculture) take this self-evidently to be a sign of progress. More output with fewer workers is seen as a measure of efficiency – and in a finite world, as they point out, efficiency matters. They also point out, with some justice, that the armies of farmworkers who were needed in the past often had to work far harder than should be asked of any human being. Peasants and slaves died young from wear and tear, and injury, infection, allergy, and hypothermia; and the less of all that, the better. Indeed, so those in positions of power tend to say, the loss of farm labour is not simply to be desired – it is a criterion of civilization. “Developed” countries – the ones that are deemed to be the most civilized, and the most desirable – have the lowest proportion of workers on the land. There is increasing interest in robots. For many, zero-labour agriculture is the goal, and it is most likely to be achieved in arable.

But again there is a downside – which, there is good reason to think, may far outweigh the hypothetical advantages. At least, it is a premise of this whole College that the prime task for all human enterprises including agriculture is to create convivial societies within a flourishing biosphere. So it becomes a prime responsibility of all enterprises to provide good jobs, both satisfying and constructive. No-one suggests (or not at least since Pol Pot) that armies of coolies should do the work of tractors. But agroecological farming of the kind the world needs must be complex, and complexity requires craft, and the various crafts of farming can be among the most satisfying of all. It is also true and obvious that the wholesale purge of agricultural labour in the cause of “efficiency” and “development” is a prime cause of unemployment and hence of the poverty which politicians the world over affect to abhor. Indeed, as many have observed, starting most famously with Jean-Jacques Rousseau in the 18th century and continuing through Ruskin and William Morris and Tolstoy and Gandhi to Schumacher and many more, too much industrialization is dehumanizing, and that is the antithesis of civilization. See various essays in Parts IV and VI. The concepts of “efficiency” and “progress” must be redefined.

Some agriculturalists who accept the general tenets of agroecology, and see that we need to do things differently, feel nonetheless that arable farming at least does have to be run on industrial lines just because it lends itself so well to industrialization, and  can then be so productive, at least for the time being. But as argued in Part I, we need to acknowledge that “enough’s enough”. Do we really need so much production? Do we need 14 tonnes-plus per hectare in East Anglia if the world as a whole already produces twice what’s needed? Some farms in some countries do need to raise productivity, or at least to make yields more reliable – but for them, two or three tonnes per hectare may often be all that’s needed, and that should not require the vast monocultures and the technological heroism of eastern England and still less of Oklahoma or the Ukraine.

It would be wrong – unjust and libellous – to suggest that all farmers who have hyper-industrialized and focused on yield these past few years and decades are simply short-sighted. Many now are seeking to farm more sustainably and resiliently. Some big, monocultural arable farmers are reintroducing livestock to recreate the mixed farming of earlier times, and to achieve this, some are inviting more farmers on to their land (see Part VII). But the commercial pressure to industrialize and to scale up is enormous. The agrochemical companies want to sell more and more, and their influence continues to grow, supported as they are by neoliberal governments who seek only (it seems) to maximize short-term GDP.

But the world as a whole needs agroecology, and a prime task right now is to apply its principles to the particular problems of arable. What this entails is discussed in Section II.3.