Eric Toensmeier is the author of several books focused on perennial cropping systems, biodiversity, and nutrition. His research, writing and experience, have led him to be a contributor to Project Drawdown, an appointed lecturer at Yale University and an international trainer. His book, The Carbon Farming Solution has been a valuable resource for building my understanding of different perennial plants and agroforestry.
As such, in August 2023, I was excited to meet Eric and joined him at his home near Holyoke, Massachusetts, a town notable for its history of paper mills, where it was once referred to as the “Paper City of the World”. In 2004, Eric established an urban farm here, the Holyoke Edible Food Forest Garden, which was featured in his first book, Paradise Lot.
Currently, in the land around his new home, Eric is developing a growing site which will be used for workshops and demonstrations. He is a fountain of knowledge on farming systems that support high quantities of carbon drawdown into landscapes. And during our conversation, he shared some fascinating examples from around the world, of farms and projects working to support climate change adaptation, while helping regenerate landscapes and the resilience of our food system.
An early interest in agroforestry and design
Eric has described himself as a product of the permaculture movement, which often has an emphasis towards perennial crops and multi-functional agroforestry systems. While these systems are more common in smaller-scale farms and homesteads in tropical climates, temperate examples also exist and in the UK, the Agroforestry Research Trust gives examples.
The promise of these highly diverse agroecological systems that mimic natural woodland is that they require less input of resources and energy, and cause the least possible damage to the environment. They also support high levels of carbon sequestration and storage, while still having the potential to achieve high productivity. As Eric explained:
…such systems of farming have existed for over 10,000 years and are still practised today around the world by smallholders. These are the farmers that do the most on a “per hectare” basis to fight climate change; have the practices that have been around for the longest and which have been well-studied and shown to work. They have done the least to cause climate change but unfortunately, they are the most affected by it. These farmers do not get the attention they deserve.
Eric Toensmeier, 2023
Highly diverse agroforestry systems can feel at polar opposite ends to the conventional agriculture systems that dominate many landscapes and food cultures today. Yet there is valuable knowledge that can be drawn from this lineage of regenerative agriculture, to support more conventional farms to become more resilient and sustainable.
Creating a Demonstration Site
We began with a tour of Eric’s growing operation, which includes a variety of annual and perennial plants. Eric pointed out various plants he is trialling, each having versatile uses and interesting characteristics. Many are not cultivated on a commercial basis in the USA, yet will be familiar to various cultures and communities around the world.
For example, Eric invited me to taste Toona sinensis (Chinese toon), a highly nutritious leaf that tasted like chicken soup and is used in Chinese cuisine. Eric is also growing Kernza, a promising perennial grain that’s been under development for many years, by organisations including the Rodale Institute and The Land Institute. He explained that breeding work is ongoing, with a goal of reaching a yield as high as quinoa, after which it should become commercially attractive.
While in the early stages, I could see that over the coming years, the site will become a beautiful space, full of abundance, for demonstration and workshops. Meanwhile, there is work to rebuild the soil health, after decades of overgrazing by a previous owner, causing excessive levels of phosphorus which has contributed to the pollution of local water courses. To help repair the soil, he’s using a variety of cover crops and trialling the use of biochar, a good technological innovation he says, but one that he considers has often been oversold.
We then walked over to a young alley-cropping system. The lines of trees contained perennial staple crops, nut trees such as chestnut, interspersed with nitrogen-fixing shrubs. The alleys in between were mainly cover crops for now, helping support improvements to the soil health.
Reflections on Livestock and Landuse
An area I was keen to hear Eric’s reflections on, was the future of livestock systems as we work to transition towards more sustainable agriculture and land use. This is prominent, since an estimated 66% of agricultural land is currently given to grazing livestock (of which, an estimated 65% is unsuitable for crop production), yet livestock provide only 38% of global protein.
This is complicated territory. Especially, the work to reconcile global perspectives and broad sustainability goals, while agreeing on regionally appropriate action – and simultaneously, taking into account issues such as nutrition, land use efficiency, ethics, jobs, animal welfare and cultural history. It’s common to meet people with strong opinions about what should be done, and it can be easy to cherry-pick scientific articles to craft narratives that fit with our existing biases.
And so I appreciated Eric’s thoughts on these matters. He seems committed to balancing a scientific and technically robust view, while acknowledging existing farming practices and cultures, with a good sense of the power dynamics at play in our food system.
There was no need for us to dwell on the significance that global livestock systems have to our planetary health (which I’ve written a bit about here). Instead, we focused on a few themes: the promises and effectiveness of regenerative grazing systems, innovations in novel feedstocks and the treacherous and difficult task of shifting public eating habits.
Regenerative Grazing Systems
A common principle within regenerative agriculture is to appropriately integrate animals into a farming system, capitalising on their ecological niche as biological up-cyclers. Many farmers are passionate about their regenerative grazing systems and those who do it well, witness several benefits for their landscape and farm business. This can include increased biodiversity, improved soil health, healthier animals and reduced external inputs, which can lead to improved profitability. Various projects and research attest to these benefits. For example, in the USA, CBF’s 2022 Farm Forward Project explored the many positive environmental outcomes from six farms as they converted from commodity cropland or continuous grazing, to regenerative grazing systems. As the saying goes, “It’s not the cow, it’s the how!”.
Today, in America’s Midwest USA, some regenerative farming enthusiasts are advocating for the incorporation of grazing livestock on the big grain farms. Done appropriately, this could make sense, especially as some of the soils have become so degraded by decades of conventional monocropping and a reliance on agrochemical inputs.
Yet, an area of complication often raised is that while regenerative livestock systems can support a more ecologically functional landscape, they require larger areas of land. On the other hand, input-intensive, conventional livestock systems produce more food from a smaller, yet degrading land base. For example, a 2018 study focused on Midwest USA suggested Adaptive Multi-Paddock Grazing systems required around twice as much land as an intensive feedlot system. Another well-discussed case study is White Oak Pastures, which was found in a peer-reviewed paper to have a carbon footprint that was 66 per cent lower than conventional beef, but with the catch that 2.5 times more land was required.
This leads to debates around the unintended consequences of agricultural sprawl if humanity’s hunger for red meat stays the same but we eat more of it from grass-fed ruminant systems. Much more land would be required, and achieving this risks encroaching onto precious remaining natural habitats (like is witnessed in Brazil), or risking the displacement of cropland production (which risks a knock-on effect of agricultural sprawl elsewhere).
Despite this, there are still benefits to shifting from extensive to regeneratively (or holistically) grazed pasture lands, and some farms suggest they can maintain or increase their production by using these practices while cutting emissions significantly. For intensive arable systems, introducing livestock presents a valuable opportunity to improve degraded land, safeguard the soils, increase nutrient cycling and reduce external inputs and pollution.
So what to make of all this? Should conventional feedlot systems play a major role in our future, to meet society’s hunger for meat? Given the poor land-use efficiency of regenerative grazing systems, how much of our landscapes should incorporate them – and where? And finally, what are the carbon opportunity costs of other land management options? Are there some landscapes, such as rougher grazing pastures, where it would be more sensible to embrace rewilding instead, to maximise the biodiversity and carbon drawdown we urgently need? Such rewilded systems would still include some ruminants, but they would only provide a negligible quantity of food. A famous UK example is Knepp Estate, which was once farmed intensively and is currently given over to rewilding (I’ve written about this here).
With most farming systems around the world reliant on subsidies, much of the future direction comes down to political will and hard economics. Will governments and industries be able to grasp these complexities and incentivise our food and agricultural systems effectively in a direction that is safest for humanity? Or will we be stuck paralysed in unresolvable debates and indecision?
In the UK, George Monbiot has been a major voice contributing to this debate (for example, here and here), forcibly critiquing some of the claims made around regenerative grazing, and this stirs outrage among many farmers. Monbiot cites articles that cast doubt and uncertainty around the carbon claims of regenerative grazing systems (such as Wang, 2023 and FCRN’s Grazed and Confused) and papers that question whether we should assume any carbon sequestered is safely stored from the atmosphere for long (e.g. Lehmann and Kleber, 2015; Soong et al, 2021; Popkin, 2021).
Clearly, curbing society’s hunger for meat would help ease pressures on land, as this analysis suggests. Yet this is often considered too sensitive for politicians to discuss and the public is largely not calling for it anyway. Meat is deeply engrained in our cuisines and cultures and despite all the hype around veganism and plant-based foods, the global trend for eating animals is upward. In America, Eric said, the appalling level of food waste is a much easier issue for governments and citizens to focus on (although difficult to fix) – and that probably rings true in the UK as well.
Don’t Forget the Trees
Understanding the role of trees in farming systems is an important aspect of Eric’s work. Promoting how they can be best incorporated on farms to maximise benefits, such as the provision of timber, fibres or nutritious foods, as well as other roles, such as beneficial shade, shelter and improving soil health, not to mention carbon sequestration and storage.
In the tropical climate of Columbia, Eric spoke passionately about their intensive silvopasture systems, some of which, he suggested, have been able to operate on a similar carbon footprint as an intensive feedlot system in the USA. Dense plantations of trees are browsed down by the animals – and some types of leaves in these systems have been identified to reduce methane emissions, while the pasture grasses in the genus Brachiaria have been found to capture nitrogen in the urine of grazing livestock before it can off-gas a N2O.
Eric believes that tropical silvopasture systems like this, can achieve intensification, emissions reduction and carbon reduction all in one package. Yet, these systems are not getting the attention they deserve. There’s a frustration in his voice: “All we hear about is holistic and adaptive grazing!!”. Yet there are so many examples of tropical farmers doing a better job, and not getting the climate finance, recognition or markets for climate-friendly meat”.
Novel Feedstocks and Foods
While it’s fascinating to explore the potential for improving our ruminant grazing systems, finding a sustainable pathway for the future of our terrestrial monogastric animals (mainly chickens and pigs) is much more challenging.
Besides the sourcing of animal feed from more regeneratively managed arable farms, the only other glimmers of hope seem to exist in novel feedstocks, such as insects, waste-to-feed innovations, or even lab-grown meat. On insects, Eric remarked, perhaps it might be more efficient for humans to eat them directly. We discussed how many of these innovations are not yet operating at scale, and some appear to have limits to their scalability, due to the feedstock, materials and electricity they require.
However, as we discussed this, Eric mentioned one potential feed (and human food) source that he felt might warrant more exploration: Leaf Protein Concentrate. A process that squeezes the juice from leaves, followed by a fractionation stage that extracts the proteins, as described in this paper. It sounded interesting, as it could be combined with perennial cropping.
Embracing Diversity and Keep Learning
Putting technological wizardry to one side, the conversation I had with Eric served as a reminder that so many of the most promising solutions in our food system are biological, not technological. Nature has given us a remarkably rich tapestry of edible plants. By sharing knowledge and working with these crops, especially the perennials, we have the ingredients to rebuild greater diversity into our landscapes and with that, more resilience. This will be critical for adapting to a changing climate. But underpinning this, greater investment into perennial crop research, education and awareness, will be crucial.
I was also reminded how agroforestry still does not get the attention it deserves. And how some of the most inspiring examples of low-carbon farming can easily get overlooked or ignored, perhaps due to cultural biases, language barriers, or because the good case studies simply get overshadowed by more mainstream agricultural narratives and popular figureheads.
Eric’s insights on livestock and grazing were honest, and science-led, with a healthy balance of admiration over practices such as holistic grazing, with an understandable frustration about how some of its advocates have overestimated its potential and misled so many people.
Leaving Toensmeier’s home, I was inspired by the richness of his knowledge and the huge opportunities that exist to improve our many degraded landscapes and build more resilient farming systems. But our time together also reminded me how complex this can sometimes get, and how we must keep challenging ourselves to step back, see the bigger picture, and keep learning.
Further reading
- Perennial Solutions – Eric Toensmeier’s website
- Books By Eric Toensmeier on Chelsea Green
- Project Drawdown