The Green New Deal: From Annual Crops to Perennial Agriculture
Lennart Olsson
In the 1920s, drought and unregulated policies created the Dust Bowl in the US Midwest. In the early1930s, rains failed in this notoriously drought prone region resulting in crop failures and soil erosion at an unprecedented scale. Hundreds of thousands of people starved and by 1940, around 2.5 million people had left the area. However, the swift and forceful New Deal response to the Dust Bowl still represents an exemplary political initiative to an environmental and humanitarian tragedy. What made the response successful was its three-pronged strategy to combine immediate short-term actions to alleviate human suffering and medium term reforms of the economic conditions for farmers and youth with long-term initiatives to strengthen research and innovation. The short-term responses reconciled political polarization and created confidence in the state, which paved the way for long-term institutional reforms.
The Green New Deal Needs a New Cropping Model
At the core of the New Deal was politics of land and soil. When a Green New Deal is now proposed there is an unprecedented opportunity to link climate change and agriculture – a hitherto missing link. Agriculture is the most polluting sector in modern society and is responsible for up to a third of the human induced emissions of greenhouse gases. Moreover, dominant trends in modern agriculture are at odds with social goals such as employment, livelihood diversity and social cohesion. A Green New Deal could be the impetus for making a long-lasting substantial contribution to climate change mitigation through promoting a perennial revolution in agriculture, i.e. a shift from annual to perennial crops.
At the core of the unsustainability of modern agriculture is the reliance on low diversity annual cropping systems that require severe ecosystem disruption every year in order to restart the production cycle. The only agricultural systems that can deliver on all the unsustainability aspects of modern agriculture are systems dominated by perennial grains cultivated in crop mixtures – polycultures. From ecological theory we can infer that annual plants, i.e. most of our food and fiber crops, are more susceptible to agricultural pests and also more dependent on external inputs of nutrients than perennial plants. When the idea of shifting from annual monocultures to perennial polycultures was first proposed by Wes Jackson in 1980 it was regarded by many as utopian. Today, thanks to rapid advances in plant sciences, the vision is within reach.
How can a Perennial Crops help in the Climate Crisis
When natural ecosystems were once converted into farmland, large amounts of carbon that had been stored in the soil in the form of organic matter were released to the atmosphere. As much as a quarter of all the CO2 emitted so far came from agricultural soils. The two most important reasons for the loss of soil carbon were tilling and the replacement of perennial plants having large and deep root systems with annual plants having tiny and shallow root systems. Today conventional cultivation of cereals is generally a carbon source. Studies in the US and France have shown that conventional cultivation of wheat can be a large source of carbon dioxide, between 6.5 and 8.2 tons CO2 ha-1year-1. In contrast, recent studies show that the newly domesticated perennial grain crop Kernza (Intermediate Wheatgrass) acts as a strong carbon sink of 13.5 tons CO2 ha-1 year-1. Imagine if the current world cultivation of wheat (about 220 Mha) was replaced by this kind of crops! The carbon sink would then be 3 Gt CO2 year-1, i.e. about three times the current annual global emission from aviation. In addition, such a shift would have the potential of significantly slashing the current emissions of several greenhouse gases from agriculture when the use of machinery and mineral fertilizers is reduced. Such a strong carbon sink is of course not possible to sustain indefinitely, and it will take another decade of plant breeding to increase the seed yield from Kernza to compete with that of wheat, but it is a sign of the huge potential.
The Green New Deal Must Focus on Perennial Crops
As a response to climate change and other environmental and social predicaments, there is a momentum in both science and policy of the necessity to develop new agricultural practices, focusing on perennial crops – a Green New Deal could provide leverage with mutual benefits to climate change mitigation and adaptation, reduced environmental degradation, and a renaissance of rural societies. Shifting from annual monocultures to perennial polycultures goes well beyond discussions about organic vs conventional or the GMO debate. The crucial question is how such radical alternatives can be implemented. A perennial revolution fundamentally challenges the current highly consolidated and powerful agro-chemical industry controlling majority of the agricultural input sector. This calls for political initiatives no less radical than the New Deal of the 1930s as well as public funding programs. In the beginning, the new perennial crops might be yielding far less than the old varieties, but systematic public research in plant sciences and agro-ecology holds promise to increase productivity of the new crops. In a time perspective of two to three decades of sustained research, there is a huge potential for perennial polycultures to outperform agriculture as we have known it for over 10,000 years.
Lennart Olsson is a
Professor of Geography at the Lund University Centre for Sustainability Studies
(LUCSUS).