Save Our Planet – it is the only one which has trees.
The equinox is when the Earth’s equator is tilted to exactly face the sun, and day and night have equal length. It is a special feature of our planet and it happens twice a year on 21st day of March and September. The 21st of March is also special for our planet as that is when we celebrate the International Day of Forests. An important day to remind us to save our planet as it is the only one we know which has trees.
350 million years ago when trees evolved, the earth was ten degrees hotter than it is today, and CO2 concentrations were ten times higher, at 4000 ppm. Trees are what made the Earth habitable for mammals, and destruction of forests will lead to the ultimate destruction of mammals – including humans. We rightfully worry about a 2-degree temperature rise but wrongly ignore, day by day, that trees in agricultural land can bring the microclimate temperature down by 4 degrees. Beyond March 21st, every day at the World Agroforestry Centre (ICRAF) is a celebration of trees for us together with the 450 million smallholder farmers of the world who rely on trees for their goods (fruit, timber, medicine) and services (erosion control, hydrological cycles and carbon sequestration).
The Economist magazine was set up to debate and argue important issues. Therefore it is enigmatic that it took 170 years since its establishment in 1843 to realize that agroforesters and foresters love to argue. This week saw the second “World Forest Summit” being held by the Economist in Stockholm, the capital city of country with an impressive 65% forest cover. The theme of the summit is “Unlocking the True Potential of Forests”, and as Director General of the World Agroforestry Centre I was invited to share some thoughts on the role of trees on farms. Enticingly, the invitation came with a plea to be provocative and therefore I framed my interventions around two unresolved topics of (a) humanity’s forest needs; and (b) global food prices.
So how much forest does the world need? After working 30 years in tropical forestry I am still yet to hear a really convincing answer. The simple response of “much more” is inadequate when we consider that 20,000 years ago the world was covered with 10% forests during the last major glaciation. Twelve thousand years later, around the birth of agriculture, this figure had increased to nearly 60%. Today we have 30% tree cover, but what do we compare this 30% value against? Is our baseline 10% or is our baseline 60%? Have we tripled historical forest cover or have we halved it?
Forest and trees give us both goods such as timber, fruit and medicines, as well as services such as erosion control, carbon sequestration and biodiversity conservation – and thus how many trees as either natural forests or on farms do we need for these goods and services? If we all had North America’s per capita paper demand that would be 7.0 billion m3 wood per year or 100 times Sweden’s total forest offtake. So if we could design and develop a new country in the middle of the Pacific Ocean what would be the amounts of land allocated to forest, to agriculture, to energy, to wetland? Would it be tilted more to forestry or to agriculture? Globally, forest area (4.1 billion hectares) is roughly the same as that for cropland, pasture and rangeland (4.3 billion hectares) but this average masks individual country extremes. Does Gabon need its 77% forest cover? Maybe not, but the world certainly does even if only as a carbon sink.
Increases in global food prices can cause huge problems. Food price riots are one of the most understandable civil actions we can all relate to. Hungry people are angry people. But if trees, and avian species, and soil organisms could protest at the disappearance of trees and forests then we would see even more extreme anger.
So how do we better balance the social, environmental and financial costs of food?
Certainly today food must be too cheap when in Europe we can throw about half of food after it is cooked, and in Africa half of food is wasted before it is cooked. Following western diets, on average, humans ideally need about 800g of food daily. This is roughly made up of 250g carbohydrate, 400g fruits and vegetable, 75g fat and 75g protein. With a combination of the best cereals, the most productive fruits and vegetables and highest yielding oil palm, all of the first 3 items could be grown on one twentieth of a hectare (0.05ha) per person. The protein part is a bit trickier. If you want to eat animal protein you need about 1 ha of land per person per year whereas if you eat vegetable protein then you could only need about 0.1 ha per person per year. With 4.1 billion ha of forest, versus 2.8 billion ha of pastures and rangelands and 1.5 billion ha of croplands it is easy to see why people are eyeing up forests for even more agricultural expansion.
The answer to both these challenges lies in aligning science, policy, development and private sector investments with social aspirations. Here perhaps gender remains the least progressed dimension with 70% of labour in developing country agriculture being provided by women but disproportionately low rates of land tenure and profit taking from women. In addition to gender, national governments, farmers and businesses are having to make decisions without the latest information, best available practices or beneficial policy environment. Successful case studies, pilots and lessons learned need to be documented and made better available.
Trees are one of the few things which live longer than humans—a true intergenerational gift. If we asked the most innovative designers, the cleverest architects and the most competent engineers to build something like a tree they would come way short of Mother Nature. But if humanity is not going to be consigned solely to a glass, plastic, steel and concrete destiny then collectively the world has to get more serious about forests and trees, and tilt our future to more sustainable use of land and forests.
As Luke Skywalker perhaps meant to say in Star Wars, “May the forest be with you”.
Related story: Forests crucial to green growth.