Kinshasa, its traffic and street vendors, receded as we drove past the international airport on the national road following the Congo River. “It’s been recently re-asphalted”, said the driver, an entrepreneur who owned a plantation on the Bateke Plateaux where the cross-country car was taking us. The plain gave way to grassy hills and valleys in which gallery forests bordered water streams. Villages with their fruit trees could be spotted at a distance. The road was not too busy, except for a few rusty lorries slowly driving in the opposite direction. They were going to the big city, loaded with bags of makala (charcoal or ember in Lingala). The loads were heavy, the vehicles old. One had broken down and stood still on the side of the renovated road connecting the savannah to urban markets. The charcoal-producing plantation I had come to visit with its manager was soon expected to contribute to these exchanges between country and city.
My trip to the Bateke Plateaux in the Democratic Republic of the Congo (DRC) was motivated by a research project on the global environmental policy known as REDD+ – for reducing emissions from deforestation and forest degradation. In the United Nations’ climate change talks, negotiators had been discussing a mechanism whereby so-called developing countries would receive incentives from public and private sources to decrease forest loss and increase forest cover. With REDD+, monetizing the metabolism of trees, in particular the quantity of carbon stored in woody tissues, was meant to fix the planet’s broken metabolism. When I arrived in Kinshasa in 2011, DRC’s ministry of environment had embraced the policy. An overseas aid program backed by UN agencies and the World Bank was in place to make the country “ready” to valorize its forests, these precious stores of carbon. International consultants were tasked with identifying interventions for a REDD+ strategy and their attention had turned to wood as an energy source: combined with shifting agriculture, it was believed to be a significant driver of deforestation (when fields are cleared, the harvested wood is usually transformed into charcoal). Another reason for the consultants’ interest in woodfuel was a set of projects established near Kinshasa, which included a couple of industrial plantations, including the one I visited, and community forestry activities. These projects aimed to make charcoal production more sustainable by reducing pressure on the savannah’s woody resources, thereby also preventing the loss of carbon. The future REDD+ strategy could encourage more interventions like these.
In this essay, I examine how tree planting has come to be popular on DRC’s Bateke Plateaux, at least among development experts. Doing so, I trace some of the relations through which Kinshasa and its hinterland have shaped each other. This is a story about wood, charcoal, acacias, money, roads, carbon, energy, as well as social structures, global policy and technical expertise. The focus, thus, moves away from the sustenance of human bodies to foreground what happens to a landscape, which provides a source of energy to cook the food that feed human bodies. The ‘metabolic’ sensibility developed here consists in attending to the material exchanges between city and woodlands and to the way in which these exchanges are conceptualized – hence the title, which is a citation of a book written by scientists concerned with the environmental impact of Kinshasa’s woodfuel consumption.
An energy-hungry city
If Kinshasa’s charcoal trade is confined to a geographically limited area, it is the object of transnational expertise. In the late 2000s, the French Agricultural Research Centre for International Development (CIRAD) partnered with Congolese, Dutch and Belgian colleagues to investigate how to “sustainably manage woodfuel resources to secure the supply of large cities in central Africa”, starting with Kinshasa. Their contention was that the city was “eating the forest”. A metabolic understanding underpinned this research-development program, drawing attention to the material flows between the metropolis and its surroundings.
The project mobilized a range of expertise in agronomy, forestry and resource economics, attuned to different issues and different scales. In the city, where an overwhelming majority of people use makala to cook food (food that also travel from the country, while money and manufactured goods make the return journey), the objective was to quantify the market. Kinshasa’s woodfuel sector appeared largely informal, there were barely any statistics and regulations were not enforced, and yet it was socially consequential. The resource economists estimated that about 300 000 people (producers, transporters, retailers) were involved in the trade of charcoal. A vital source of income to many poor households, the commercial activity was also believed to be unsustainable. The experts assessed that, in 2010, the renovated road crossing the Bateke Plateaux had carried nearly half of the 490 000 tons of charcoal sold in Kinshasa that year. Lots of trees were sacrificed for this, as shown in their quantification of tree cover loss based on satellite images and field measurements of the remaining biomass. The scientists, thus, concluded that the 8 million Kinois were exerting a strong pressure on the woody resources of the “supply basin”. At this rate, the savannah and its carbon stocks could soon be digested by a voracious city, leaving behind only grass on impoverished soils unable to sustain livelihoods. Woodfuel would then have to come from farther, via the river from the rainforest.
The eating metaphor clearly alerts to an unhealthy relation between urban consumers, rural producers and the environments. This relation was in need of a fix and the question was how. Charcoal-makers, the experts observed, had already optimized their craft. In their earth mound kilns, the combustion of wood obtained from fallow and gallery forests was carried out so as to maximize the quantity of carbon in the final product, achieving high yields of energetic charcoal. Solving the metabolic imbalance would require to intervene further upstream and increase the supply of raw material by encouraging villagers to enrich Kinshasa’s hinterland with trees. Scholars such as Diana Davis, James Fairhead and Melissa Leach have documented how in North and West Africa, French colonial authorities had enforced coercive afforestation policy because they saw pockets of trees in non-forest landscapes as residual forests degraded by farming practices, even though people had often planted those trees. While the focus on trees in CIRAD’s project resonates with this colonial “arboreal biopolitics”, it was meant to be much less disruptive. Aware that development projects fail when the context in which they are implemented is ignored, the foresters tried to understand how each village had so far managed the landscape, before putting forward what they deemed to be further improvements – participatory land use planning, firing methods that facilitate regrowth, planting trials to demonstrate the feasibility of agroforestry. The rural reality was translated into tables, maps, technical itineraries. The expectation was that future tree planting projects, like those envisioned in relation to REDD+, would draw on this knowledge repertoire.
In the project just discussed, community forestry was conceived as a response to a century-old alarmist discourse about resource depletion, now linked to the latest environmental crisis, climate change. Woodfuel had, actually, been a global concern not so long before. In the 1970s, it was talked about as the other energy crisis. Soon, FAO’s experts announced, two billion people in Asia and Africa could experience energy scarcity due to forestland degradation and plantations were posited to prevent this from happening. In the following decades, as the anticipated disaster did not materialize and tree planting failed to scale up, woodfuel fell out of fashion amongst donors. Though short-lived, this anxiety about a metabolic imbalance between forest resources and energy needs has left visible traces in DRC’s savannah.
In the mid 1970s, when the Zairean state decided it would plant 100 000 hectares, a research station was set up on the Bateke Plateaux and field trials were conducted to identify suitable species.  Planting effectively began in 1987 as a development project supported by European sponsors. A few thousand hectares were covered with acacias when things stalled in 1991. Riots and lootings had spread across cities, especially Kinshasa, as a famished population, aided by the military, revolted against poverty and a predatory political regime. The afforestation activity eventually resumed and carried on during the Congo wars. A German foundation and a Congolese civil society organization recruited farmers interested in owning plots in the plantation, which needed stewardship against bush fires. Around 1997, the farmers started a first production cycle, cutting down trees, carbonizing their wood, and burning residues to fertilize the fields. The heat would also activate dormant acacia seeds so that a next generation could grow. The species Acacia auriculiformis had been chosen precisely for the dual purpose of agriculture and forestry. Its wood gave good quality charcoal, while the tree’s symbiotic relation with nitrogen-fixing bacteria enriched the soil for the crops (cassava, the staple food, and maize, a cash crop). The hot and humid savannah in Kinshasa’s hinterland thus joined the list of places where Australian acacias have settled in their global history. Twenty-five years after the first trees took root, the plantation supplied roughly 1% of urban woodfuel consumption. This was a small step towards sustainability, which was nevertheless heralded as a success by development experts, including CIRAD’s scientists who were promoting the use of acacias in their community-based activities.
On the Bateke Plateaux, acacias trees also acclimated well to new environmental concerns. In the early 2000s, as peacebuilding got underway in what was now DRC, growing international awareness of climate change revived an interest in woodfuel. A local yet well connected entrepreneur saw in the acacia plantation a blueprint for his own tree planting venture. The business model was, first, to valorize the trees as stores of carbon and, in the longer term, commercialize charcoal. Support from a World Bank program was secured, technical advisors hired. A multinational food company looking to offset its carbon footprint expressed interest in buying the future emissions reductions. The sale would help repay the invested capital. But when I visited the site in 2011, a preliminary assessment of the young plantation suggested that its carbon-storage potential might have been overestimated. An audit later confirmed that only a tiny fraction of the anticipated volume of offsets could be issued and development money had to be raised to save the project and its acacias.
Regardless of this cautionary tale, the consultants working on DRC’s REDD+ strategy in the early 2010s were tree-planting enthusiasts. CIRAD’s community-based activities and the two industrial plantations had set their focus on woodfuel. At the ministry of environment in Kinshasa, I attended discussions about “REDD+ pilot projects”, which included one more agroforestry initiative on the Bateke Plateaux. Here villagers would be encouraged to give up shifting agriculture and, instead, grow acacias to make the savannah cultivable and produce charcoal. A few years into the project, a Belgium-based anthropologist went to conduct fieldwork in three participant villages, asking why in only one was agroforestry implemented as planned. She identified several factors: the nearby presence of gallery forests, distance to roads (including the renovated road to Kinshasa), dependence on subsistence agriculture and land ownership. For example, in a village where tree planting failed to convince, Teke right holders were lending their plots to landless migrants. These workers had no desire to bear the extra burden of caring for trees that would take a decade to reach maturity on someone else’s land. REDD+, with its promise of payment for the loss of carbon avoided by letting fallow forests regenerate, could not wipe out the social structure embedded in this landscape.
From supply to demand
In the last few years, the metabolic reasoning of development experts has expanded beyond the savannah, as illustrated by a new project seeking to convince urban consumers to adopt energy-efficient cookstoves, or even switch to liquified petroleum gas.  In international policy circles, so-called improved stoves had been considered during the 1970s woodfuel crisis, but large-scale dissemination did not happen. The technology later recaptured donors’ attention as a health measure against indoor air pollution and, recently, stove projects have been popular in the carbon offsetting markets. It is now hoped that increasing the efficiency of cookstoves in Kinshasa will decrease the use of charcoal. The aim is still to reduce forest losses linked to (unsustainable) woodfuel as the attention shifts from acacias plantations and earth mound kilns, to urban kitchens and cooking habits. 
This essay engaged with the metabolic thinking that scientific foresters have applied to the landscape stretching eastward from Kinshasa, DRC. The Bateke Plateaux is said to be transformed by the energy consumption of the metropolis and past and present, global and national development policy. The current situation may be described as a state of metabolic imbalance: the woody savannah and its carbon stocks would soon be unable to satisfy urban energy needs. Diagnosing an imbalance, a deficiency, or a gap, helps to justify the intervention of expertise and technology. To prevent the city from eating the forest, the response has been to encourage some people to grow more trees and others to use charcoal more efficiently.
It is beyond the scope of this essay to make claims about the extent to which woodfuel and shifting agriculture are causing carbon losses in DRC. Historical examples of African landscapes being misread encourage caution when it comes to assign blame for environmental destruction. What is clear though, is that farmers, charcoal producers, and the urban poor bear no responsibility for the climate crisis, and yet, here they are embroiled in it. Far from presenting a definite picture, this essay is an invitation to take a wider range of analyses into account – from semi-failures or semi-successes, to locally meaningful ways to cope – to better understand what is happening in this landscape bordering the rainforest, where city and woodlands exchange matter, energy and money, along a re-asphalted road, via unequal social relations, under the impulse of policy fads, in a context of chronic poverty. At a time of planetary changes, which have become known through large datasets, it also matters to tell such finer-grained stories, in which current dominant concerns, like carbon, are positioned among other issues and their own history.
 Fieldnotes, Bateke Plateaux, 22 April 2011.
 On the co-constitutive relations between city and countryside, William Cronon, Nature’s Metropolis: Chicago and the Great West (London: W.W. Norton & Company, 1991).
 Jean-Noël Marien, Emilien Dubiez, Dominique Louppe, Adélaïde Larzillière (eds.), Quand la ville mange la forêt: Les défis du bois-énergie en Afrique centrale (Versailles: Editions Quae, 2014).
 Marien, Quand la ville mange la forêt, 16.
 Jolien Schure, Verina Ingram, Claude Akalakou-Mayimba, Bois énergie en RDC: Analyse de la filière des villes de Kinshasa et Kisangani (Yaoundé: Center for International Forestry Research, 2011): 61-4.
 Valery Gond, et al., “Forest cover and carbon stock change dynamics in the Democratic Republic of Congo: Case of the wood-fuel supply basin of Kinshasa,” Bois et Forêts des Tropiques 327 (2016): 19-28.
 To eat is a metaphor used in central Africa to discuss corruption, see the entry for bouffer in Nic Cheeseman, Eloïse Bertrand, Sa’eed Husaini, A dictionary of African politics (Oxford: Oxford University Press, 2019). Thomas Cousins suggested this reference.
 Ibid., 95-106.
 James Fairhead, Melissa Leach, Misreading the African landscape: society and ecology in a forest-savanna mosaic (Cambridge: Cambridge University Press, 1996); Diane Davis, “Desert ‘wastes’ of the Maghreb: desertification narratives in French colonial environmental history of North Africa,” Cultural geographies 11(2004): 359-387.
 Diana Davis, Paul Robbins, “Ecologies of the colonial present: Pathological forestry from the taux de boisement to civilized plantations,” Environment and Planning E: Nature and Space, 1 (2018): 447-469 (462).
 Michael Arnold, Gunnar Köhlin, Reidar Persson, Gilian Shepherd, Fuelwood revisited: What has changed in the last decade, (Jakarta: Center for International Forestry Research, 2003).
 Marien, Quand la ville mange la forêt, 135-7.
 Sabakinu Kivilu, “Pauvreté et misère: Éléments pour une économie politique des pillages,” Canadian Journal of African Studies/La Revue canadienne des études africaines 33 (1999): 448-482.
 Marien, Quand la ville mange la forêt, 135-7.
 Jane Carruthers, Libby Robin, Johan P. Hattingh, Christian A. Kull, Haripriya Rangan, Brian W. van Wilgen, “A native at home and abroad: the history, politics, ethics and aesthetics of acacias,” Diversity and Distributions 17 (2011): 810-821.
 Marien, Quand la ville mange la forêt, 190.
 Véra Ehrenstein, Fabian Muniesa, “The conditional sink: counterfactual display in the valuation of a carbon offsetting reforestation project,” Valuation Studies 1 (2013): 161-188.
 Camille Reyniers, “Agroforesterie et déforestation en République démocratique du Congo. Miracle ou mirage environnemental ?,” Mondes en développement 3 (2019): 113-132; Camille Reyniers, Alain Karsenty, Cédric Vermeulen, “Les paysans sans terre et REDD+ en RDC,” Conjonctures congolaises 2015 (2016): 199-226.
 Adeniyi Asiyanbi, Kate Massarella, “Transformation is what you expect, models are what you get: REDD+ and models in conservation and development,” Journal of Political Ecology 27 (2020): 476-495.
 Emilien Dubiez and Régis Peltier, “Rapport de mission réalisée du 04 au 5 mars 2019, sur le plateau Bateke, R. D. Congo, à Kinzono, Imbu et Ntsio,” CIRAD, Montpellier (26 March 2019), available at: https://agritrop.cirad.fr/591789/ (last accessed 22 March 2022).
 Fernando R. Manibog, “Improved cooking stoves in developing countries: problems and opportunities,” Annual Review of Energy, 9(1984): 199-227.
 Liquefied petroleum gas is more energetic than charcoal but it can be considered to emit less carbon dioxide only if one assumes that woodfuel leads to depletion, Fonds National REDD+ de la RDC, “Programme de consommation durable et substitution partielle au bois énergie,” Central African Forest Initiative (8 November 2018), available at: https://www.cafi.org/countries/democratic-republic-congo/sustainable-wood-energy (last accessed 22 March 2022).