In a Nutshell

Chestnuts from Italy

“This chestnut orchard (or forest as one may call it) spread along the mountainside as far as the eye could see. The expanse of broad-topped, fruitful trees was interspersed with a string of villages of stone houses. The villages were connected by a good road that wound horizontally in and out along the projections and coves of the mountainside. These grafted chestnut orchards produced an annual crop of food for men, horses, cows, pigs, sheep, and goats, and a by-crop of wood. Thus for centuries trees had supported the families that lived in the Corsican villages. The mountainside was uneroded, intact, and capable of continuing indefinitely its support for the generations of men.” J. Russell Smith. Tree Crops: A Permanent Agriculture, 1929

When Russell Smith rode through Corsica in the 1920s he saw chestnut trees growing on stony mountain slopes where most other crops could never grow. The land didn’t need irrigating or fertilizing or plowing, and hardly required attention from the villagers before harvesting the tasty, nutritious nuts in September. Chestnuts were called “the food of laziness.” They were a staple in the local diet, versatile ingredients of many recipes, and could be milled to make flour, although chestnut bread cannot rise without gluten. The trees provided a surplus for hogs to eat, imparting a delicious “woody” flavor to the meat, and the logs made sturdy furniture and house sidings and fence posts that wouldn’t rot.

His visit nearly a century ago left a deep impression on him. A single species of nut tree had helped to sustain the Corsicans in their mountain fastness since the Roman Empire, whereas in another rugged terrain in Appalachia he knew farmers struggling on land that soon became impoverished. They had cleared the old forest to grow corn and other annual crops, but after the harvest there was little ground cover for holding back the topsoil from washing downhill into the creeks towards the ocean. Russell Smith thought they were bound to fail because “farming should fit the land”.

Farmhouse north of Dalhart, TX 1938. Dorothea Lange. Library of Congress.

He published Tree Crops the year of the Wall Street crash. It was the last of a series of wet years in the Midwest before a drought visited the Great Plains of America for years, and the Great Depression spread across the country. The prairies had been a stable biome for eons because the topsoil was anchored by prairie grasses and fertilized by bison and other grazers. But like the mountain men, prairie farmers were cultivating land as their ancestors had in Europe where agricultural practices had evolved over centuries in a gentler climate. After plowing deeply for planting and leaving the ground bare in winter after gathering the cereal and cotton crops the dry topsoil blew away in great swirling clouds, some of the dust settling as far away as New York. The Dustbowl gave new meaning to a pejorative label, “dirt poor farmers,” and the calamity forced Oakies like the Joads and many others in neighboring states to abandon Grapes of Wrath country. After departing west along Route 66 with all their possessions and hopes loaded in a caravan of old trucks, the farm gates were still swinging in the wind when modern agribusiness took over.

1939 edition

Perhaps erosion of rich soil and the accompanying human suffering were avoidable. Russell Smith believed it was folly to grow annual crops incessantly on land that was exposed to the elements.  The Corsicans had hit on an answer that he called “permanent agriculture” (or “permaculture”). It was unrealistic and unnecessary to abandon annual crops, but there was an enormous unrealized potential for expanding productive orchards and planting rows of trees to protect fields; besides, some nut trees thrive on ground that is too rocky or steep or prone to flooding for cultivating annuals. Nut trees can be harvested every year without replanting, and don’t need concentrated fertilizers or soil tilling or watering from aquifers. Trees can stabilize soil structure and improve its nitrogen content, as well as provide perennial wildlife shelters and absorb huge volumes of carbon dioxide. Admittedly, some trees produce a superabundant harvest in mast years followed by a series of lean years, which is commercially undesirable. But this problem was not insuperable, and two of his friends at the forefront of horticulture technology, Robert Morris and William Deming, were already creating cultivars for cropping more consistently.

Today there is a large range of cultivars of nut and fruit trees—almonds, walnuts, pecans, pistachios, apples, pears, cherries, nectarines, etc., but if Russell Smith came back he would be sad to see we are even more dependent now on annual crops—mainly corn, wheat and soybeans—and only a few high-yielding varieties of each. He would fear that a small number of annual crops is a precarious food supply. Many agronomists in his day thought that food production would not keep up with the world’s population, which the English actuary Thomas Robert Malthus (1766-1834) predicted would lead to catastrophe. They did not live to see the Green Revolution led by Norman Borlaug in the 1960s which, through efficient irrigation and application of pesticides and fertilizers, as well as new varieties of cereal and other crops, could keep the world fed ahead of its numbers.

Cereals are now a smaller fraction of the American household budget than at any time in  history, and form a larger portion of the diet. According to the World Food Programme, hunger kills more people in the world than the three major infectious diseases combined, but the statistics are improving. And although US farmers always have worries, government subsidies have supported their commodity prices and crop insurance to the tune of nearly $300 bn from 1995-2010 (family farms receive little benefit). Our society seems to have little reason to consider large-scale changes to agronomy while people are well-fed and we are sheltered from the draught of the real price of growing food and the environmental costs of modern agriculture, which will be paid by future generations. Tree crops have little of the economic or political gravitas of cereals, and advocates can be regarded as nuts, except in the state that has them in order—California.

Seen from the air, almond orchards in the Central Valley stretch from horizon to horizon in rows of trees so straight they look like lines of longitude. California produces 80% of the world’s crop of shelled almonds, amounting to 2 billion pounds this year with a gross value of $2.8 bn. As the state’s top agricultural export, almonds are a huge success story, but the industry follows the same philosophy that created great oceans of cereals in the Midwest—monocultures on land purged of other life forms. This is not how permanent agriculture was envisioned by pioneer thinkers, nor its modern advocates like Philip Rutter in Minnesota and Peter Kahn at Rutgers University. Besides, the industry is facing challenges.

Unlike wind-pollinated grain crops, almond trees need insects for their flowers to set seed. Early in the year commercial beekeepers from all over the country transport a million beehives to the Valley for the largest controlled pollination program in the world. But their services have been seriously undermined by colony collapse disorder. Plant scientists have responded by making hybrid almond trees that are self-pollinating, hoping to maintain the size and quality of the harvest. In parts of China where bees are in even shorter supply, orchard workers pollinate trees by hand using brushes and swabs, which would be uneconomic here. Maybe drones will be recruited in future. I don’t mean the lazy male bees whose raison d’être is sex with the queen, but something like the hummingbird drones said to be in production for the Pentagon! Much as I admire feats of engineering, I wonder if ascent up a technological spiral in which fixes are regularly needed to repair fixes below is the only answer. Some farmers have always set aside portions of land to grow perennials to protect ground crops, which provides food for bees the year round so they don’t have to be moved after a single flowering crop, and are less likely to be exposed to diseases, parasites, and pesticides from traveling around the country.

There were still plenty of honey bees when Russell Smith and his friends proposed permanent agriculture, but they were not blind to problems that tree crops face. Four billion wonderfully productive American chestnut trees died off in the early decades of the century from an Asian blight and ink disease was felling chestnuts across Europe, and eventually Corsica. Since then, so many other trees have succumbed to disease. The trio were not dreamers and their scientific outlook turned their heads to plant breeding technology for creating resistant varieties, which was in its infancy then. The technology progresses slowly because hybrid trees cannot be tested for resistance to a disease for several years, which transgenic technology promises to accelerate.

Not all nuts are nuts in a strict botanical sense. Almonds are drupes and peanuts are legumes, but they have honorary nut status here as edible seeds. As reproductive parts of plants, they are uncommonly nutritious, and somewhat equivalent in food value to eggs in animals.

One day chestnuts will be abundant again, though not in my lifetime. At this time of year we used to buy expensive bags of chestnuts from street vendors who you can still see inthe streets of London and New York. Sometimes we took them home to cook on our own coals, like the Nat King Cole song. But they were only for the festive season, and when we ate them we never enjoyed a warm thought of being nourished. Nowadays, however, nuts are regarded as an almost perfect food and are key ingredients in the renowned Mediterranean diet.

Nuts are rich in proteins containing essential amino acids, and good sources of antioxidants, fiber, and micronutrients. They contain beneficial minerals (iron, magnesium, zinc, etc.) and vitamins: vitamin A (butternuts, chestnuts, pistachios, hickory nuts), vitamin C (chestnuts), vitamin E (almonds), vitamin K (cashew nuts, pine nuts) and folate (ginkgo nuts, peanuts).  None of them contain gluten, which is welcome news for people with celiac disease and the much larger number whose sensitivity  causes a broad spectrum of symptoms. Chestnuts contain the most carbohydrates, but have a low glycemic index. Acorns are rich in carbohydrates too, and if the bitter tannins are first extracted from acorns of some species of oak trees they are edible (I’m told).Not all nuts are nuts in a strict botanical sense. Almonds are drupes and peanuts are legumes, but they have honorary status here as edible seeds. As reproductive parts of plants, they are uncommonly nutritious, and somewhat equivalent in food value to eggs in animals.

Nut nutrition
Nuts & Nutrition

Most nuts have a lot of fats, which used to sound bad but now chimes with a vogue for low-carb diets. Consequently, they have more energy for the same weight than grain cereals, and are a more sustaining. Nuts don’t contain cholesterol (nor trans fats, of course), but being loaded with mono- and polyunsaturated fatty acids (MUFAs,PUFAs) they are healthy for the heart and circulation, and beneficial for the brain (a very fatty organ). Large scale studies in America and Britain have shown that people who eat nuts regularly live longer and healthier lives. That doesn’t necessarily mean they were directly responsible for better health because dietary studies rarely have the scientific rigor of drug trials, though plausibly a food that has probably been consumed almost forever is more beneficial than grains that we have only eaten in quantity for a few thousand years. There is always a caveat in biology. Nut allergies affect 1% of us, but, generally speaking, there are so many good reasons for going against the grain and nibbling more nuts. They are so much more tasty than Wonder Bread, but unfortunately more expensive.

When Russell Smith visited Corsica chestnuts were cheap, and chestnut flour was regarded as poor man’s food. Finding wheat flour in a kitchen was then a sign of prosperity.  Likewise, before the blight, American chestnut trees littered the autumnal forest floor with a green carpet of pregnant burrs. You could gather for free as many nuts as you could carry, but most were left to rot. Today at a well-known online retailer, chestnuts, almonds, and walnuts are being sold at around $10 a pound. Hazelnuts and macadamia nuts cost more, and only peanuts are relatively cheap at a third of true nuts. But the equivalent weight of wheat flour or corn meal is barely $1.00. We rarely value things while they are common, and commodities that were cheap can become luxuries when they become rare. Perhaps now that we realize nuts are valuable in so many ways we will take a closer look at permanent agriculture.

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