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Wheat yields hit new records thanks to precision farming

My Times column on farm yields and the prospects for feeding the world in future:


This week’s autumn equinox is traditionally the time for the harvest festival. I have just taken a ride on the combine harvester cutting wheat on my farm. It is such a sophisticated threshing machine that long gone are the days when I could be trusted to take the controls during the lunch break. A screen showed how the GPS was steering it, inch-perfect and hands-free, along the edge of the unharvested crop; another screen gave an instant readout of the yield. It was averaging over five tonnes per acre (or 12 tonnes per hectare) — a record.

My farm is not alone in this. Everywhere in Britain this autumn, at least where the August downpours did not flatten and rot the crops, yields have broken records.

In the Lincolnshire Wolds, Tim Lamyman smashed the world record for wheat yield per acre, held for the past five years by a New Zealander. He also set a new world record for oilseed rape yield — he did this last year too, but lost it over the winter to a New Zealander. (Britain and New Zealand have the right combination of day length and soil moisture that breeds big wheat and rape crops.)

Unfortunately for farmers, this extraordinary harvest cannot make up for the steep fall in prices, and farm incomes will be down, not up. Bumper crops elsewhere are the main reason for those low prices. Globally, the cereal harvest this year will be very close to last year’s huge record. The Food and Agriculture Organisation’s food price index is now well below where it was throughout the 1960s and 1970s: that is to say, it’s proving cheaper and easier to feed seven billion today than it was to feed three billion in 1960.

This was not supposed to happen. Food prices rose in 2008 and again sharply in 2011, encouraging those who foresaw a Malthusian breaking point, where population would outstrip food supply. The eco-gloomsters who had talked for decades about a coming food crisis, even while famines faded, thought their day had come at last.

Yet the 2008-13 hump in food prices, which hurt poor people but helped farmers, was largely caused by Europe’s and America’s barmy decision, at the behest of the eco-gloomsters, to feed 5 per cent of the world’s grain crop to motor cars instead of people, in the mistaken belief that this was somehow good for the environment. We are still doing that, but at least we’ve stopped increasing the amount, so each year’s harvest increase can now go into food.

Last week, my fields were yielding 60 or 70 grains (seeds) of wheat for every grain that had been planted a year before. This would astonish our ancestors. A farmer in England in the 1300s was lucky to get four grains for every grain he planted. One of those four had to be saved for next year’s planting, leaving a precarious three to feed not only his own family but the various chiefs, priests and thieves who fed off him.

The truly surprising thing about this bounty is that not only are yields going up and up, in Britain as in the rest of the world, but that the amount of land required to produce that food is going down; and so is the amount of pesticide and fertiliser. Not just in relative terms, but in absolute terms.

The acreage devoted to wheat and barley in Britain has fallen by 25 per cent since the 1980s. Pesticide usage in this country has halved since 1990. Nitrogen consumption in agriculture is now 40 per cent below the level of the 1980s, while mineral phosphorus and potassium use are down by 60 per cent — though that is partly because more sewage and chicken excrement are being treated and recycled for use on farms.

The world cereal harvest grew by 20 per cent in the past ten years (cereals provide 65 per cent of our calories). It needs to grow by another 70 per cent in the next 35 years to feed 2050’s nine billion people, probably with more affluent tastes.

It is on track to do so and to release a huge area from growing food at the same time. That means more nature reserves, more golf courses, more horsey-culture and hobby farming, more forests and wild land.

Jesse Ausubel, of Rockefeller University in New York, has run the numbers. To paraphrase his paper with British examples, if we keep lifting average yields towards the demonstrated levels of Tim Lamyman, stop feeding wheat to cars and rape to lorries, restrain our diets lightly and reduce waste, then an area the size of India could be released globally from agriculture over the next 50 years.

In the 19th century, the world increased its harvest by breaking new ground — in North America, Russia, Argentina and Australia. In the early 20th century it increased the harvest by replacing horses with tractors and releasing the land used to grow hay for horses. In the late 20th century the harvest went up because of synthetic fertiliser, which does not need land to produce it as manure does. Short-strawed wheats, better pesticides and safer storage and transport helped too.

Today, precision farming is driving the harvest up. Satellites tell farmers exactly which parts of each field should get more or fewer seeds, more or less fertiliser. Less wasteful fertilisers that do not escape into weeds or the local water course are coming. Better varieties are arriving all the time, though wheat harvests are now dwarfed, worldwide, by maize, which is benefiting from genetic modification. Pesticides, growth regulators, mineral supplements — all can now be fine-tuned to give the most benefit and do the least collateral harm.

Meanwhile the efficiency with which a chicken turns feed into meat has roughly trebled in the past 50 years, so even meat farming is constantly cutting the size of its ecological footprint.

From the point of view of farmers’ incomes, this is not a happy picture. With population growth slowing all the time, and Africa rapidly joining Asia in using new machinery, better varieties and more fertiliser, the world may be glutted with food for the rest of the century, keeping prices low.

Barring disasters, of course. Luddite greens are determined to prevent genetic and chemical innovations that are good for the planet as well as the harvest. A massive volcanic eruption could cause a global famine. But meanwhile, bountiful harvests mean more space for nature.

By Matt Ridley | Tagged:  rational-optimist  the-times