Coffee Climbs the Mountain: Warming Drives an Unexpected Reforestation Boom in Ethiopia

In the misty Afromontane mountains of southwestern Ethiopia, where wild Arabica coffee has grown for millennia beneath the canopy of moist evergreen forests, something remarkable is happening. Farmers who live at elevations long considered far too cold for coffee cultivation are ripping up their annual crop fields and planting coffee instead. A new study published in the journal Ambio documents this quiet revolution in detail, and its findings upend a familiar narrative: rather than climate change simply destroying coffee-growing regions, rising temperatures are pushing coffee farming uphill, and in doing so, they are triggering an unexpected wave of reforestation in one of the world’s most important biodiversity hotspots.

The research, led by Firew Bekele Abebe of Addis Ababa University and Haramaya University together with colleagues at Stockholm University and the Swedish University of Agricultural Sciences, focused on the Gomma and Gera districts in the Jimma zone, a landscape of forest fragments, crop fields, grazing lands and coffee farms. Traditionally, Arabica coffee in its native range has been cultivated only between roughly 1,200 and 2,000 meters above sea level, a narrow band dictated by the plant’s acute sensitivity to temperature. Above that line, the highlands were considered unsuitable. Yet when the researchers surveyed sites between 2,007 and 2,358 meters, they found thriving young coffee agroforests established by smallholder farmers who had made a calculated bet on a warming world.

To understand why farmers were moving uphill, the team conducted semi-structured interviews with thirty farmers who had recently established coffee agroforestry in this novel elevational range, paired with thirty neighboring farmers who had not yet made the switch. The results were striking in their consistency. Every single interviewed farmer cited climate change as a major reason for establishing coffee at these previously inhospitable heights, and 93 percent specifically pointed to rising temperatures. Two farmers added that rainfall, once too abundant for coffee, had declined enough to make cultivation viable. Crucially, this was not a story of government mandates or external pressure; it was farmers responding accurately to meteorologically real changes they had observed on their own land.

Climate was not the only driver. Just over half of the farmers said they wanted a higher and more stable income, since coffee is a perennial cash crop whose global prices are currently high. Nearly a third reported another, more surprising motivation: crop raiding. Baboons, monkeys and wild pigs were devastating their maize, teff and sorghum fields, and converting annual cropland into shaded coffee agroforests offered both a new revenue stream and a partial escape from wildlife losses. The idea itself spread through social networks, with 40 percent of farmers crediting neighbors as the source of the idea and nearly half naming neighbors as their primary source of knowledge about how to grow coffee, a pattern that hints at powerful social contagion in land-use change.

The consequences of this upward shift for biodiversity were a central question of the study, because agroforestry can cut two very different ways for conservation. When coffee is established inside existing forests, management typically thins the canopy and reduces the structural complexity that forest-associated species depend on. When it is established on open land, however, it functions as a form of ecological restoration, adding tree cover, shade, carbon storage, soil fertility and erosion control to landscapes that previously had none. The fate of the novel coffee zone therefore hinged on a deceptively simple question: were the new agroforests carved out of remaining forest, or planted on open land?

The answer was overwhelmingly the latter. Seventy-three percent of the surveyed farmers had established their coffee agroforests on open land such as former cropland or grazing areas, a pattern the researchers attribute to the scarcity of forest in the novel range and to state ownership of most remaining forest, which limits farmers’ ability to convert it. Even more encouraging were the vegetation surveys. In 30-by-30-meter plots at each site, the team counted, identified and measured every tree and shrub with a trunk diameter of at least five centimeters, along with saplings. Forest-derived and open-land-derived agroforests showed statistically indistinguishable species richness, Shannon diversity and abundance for both adult woody plants and saplings, a finding that contradicts the common assumption that agroforests established on open land are biodiversity-poor imitations of the real thing.

There were differences, to be sure. Trees in forest-derived agroforests were thicker at breast height, reflecting the presence of old, mature individuals, and community composition differed subtly between the two types, with species such as Croton macrostachyus, Ficus sur and Millettia ferruginea more abundant in forest-derived plots and Vernonia amygdalina more common in open-land plots. But the most notable feature was the extensive overlap in composition. Unlike open-land agroforests elsewhere in the tropics, which are often dominated by a handful of non-native shade trees, the Ethiopian agroforests in the novel range were built from a diverse set of native species, either planted from seeds and saplings gathered in nearby forest or regenerated naturally from seed banks and adjacent woodland. Management choices, whether trees were planted, allowed to regenerate naturally, or both, left little imprint on the resulting communities, suggesting that native tree recruitment in this landscape is remarkably resilient.

The forward-looking part of the study may prove the most consequential. When the researchers asked the thirty neighboring farmers without coffee whether they planned to establish it, 87 percent said yes, and all but one of those planned to plant on open land rather than in forest. Every one of these prospective adopters expected a better income, and half anticipated no challenges at all beyond the well-known burden of high initial investment costs, which was also the only disadvantage cited by established farmers. The researchers identify two positive feedback mechanisms that should accelerate adoption. First, farmers imitate successful neighbors, so each new agroforest becomes a visible advertisement for the next. Second, a crop-raiding spiral may take hold: as more of the landscape converts to woody agroforestry, wild animals gain more shelter and raiding pressure on remaining annual crop fields intensifies, pushing still more farmers toward coffee.

The implications ripple outward from the Jimma highlands. Modeling studies have warned that 39 to 59 percent of the land currently suitable for Arabica coffee in Ethiopia could become unsuitable by the end of the century, threatening the livelihoods of millions of smallholders and the genetic reservoir of the crop itself. An upward migration of coffee farming has long been proposed as an adaptation pathway, and this study provides the first detailed empirical evidence that the migration is already underway, driven not by top-down policy but by farmers’ own accurate perceptions of a changing climate. Because the new agroforests are overwhelmingly established on open land and are rich in native woody species, the shift is expected to increase tree cover, biodiversity and ecosystem services, including carbon sequestration, shade, soil water regulation and erosion control, at higher elevations of the Afromontane landscape, an area that has historically suffered some of the region’s highest deforestation rates precisely because coffee agroforestry was absent there.

The authors are careful to note the caveats. The full landscape-scale consequences for forestation will require quantifying natural forest cover, mapping tenure rights and assessing how regulations are observed in practice, and complementary studies at the lower edge of the coffee range are needed to understand the complete regional picture. Hidden social costs, including increased household labor burdens and effects on children’s schooling documented in earlier work, also deserve attention. Yet the core finding stands as a rare piece of good news at the intersection of climate change, agriculture and conservation: in the birthplace of Arabica coffee, a warming world is nudging an entire farming system upslope, and the farms it leaves behind on the open hillsides are filling with native trees. What looks like retreat may, in this corner of Ethiopia, be a quiet expansion of the forest itself.

Subject of Research: Climate-driven upward shift of Arabica coffee agroforestry and its reforestation consequences in southwestern Ethiopia

Article Title: Climate-mediated upward shift of coffee agroforestry and associated reforestation in Arabica coffee’s native range

Article References: Abebe, F. B., Hylander, K., Nemomissa, S., Bekele, T., Zewdie, B., & Tack, A. J. M. (2026). Climate-mediated upward shift of coffee agroforestry and associated reforestation in Arabica coffee’s native range. Ambio. https://doi.org/10.1007/s13280-026-02470-3

Image Credits: AI Generated

DOI: 10.1007/s13280-026-02470-3

Keywords: climate change, coffee agroforestry, Arabica coffee, Ethiopia, Afromontane forests, reforestation, biodiversity, ecosystem services, smallholder farmers, elevational shift, crop raiding, tree cover