Ethiopia planted eucalyptus to fight deforestation; decades later scientists found the trees can threaten springs and water supplies

Eucalyptus trees were introduced to Ethiopia more than a century ago as the country struggled with shortages of firewood and construction timber. Their rapid growth made them an attractive answer to the pressure on natural forests, and later government reforestation programmes encouraged their wider planting. Over time, eucalyptus became one of the most widely planted trees in the country, supplying fuelwood, timber and income while reducing some of the demand that drives deforestation. But decades of expansion have also exposed a difficult trade-off: trees planted to ease pressure on forests can consume substantial amounts of water in areas where supplies are already limited. A 2025 review, ‘Socioeconomic and Environmental Impacts of Eucalyptus Plantations in Ethiopia: An Evaluation of Benefits, Challenges, and Sustainable Practices,’ by Kiros Getachew Belachew and Wondwosson Kibrie Minale, examined these competing effects.How eucalyptus became a solution to Ethiopia’s deforestation problemEucalyptus first arrived in Ethiopia in the late 19th century, when it was planted to address shortages of firewood and construction wood around the capital. Its appeal was straightforward: the trees grow quickly, produce useful timber and can provide a regular source of income for households. As demand for wood increased with population growth, agriculture, construction and energy needs, eucalyptus spread far beyond the areas where it was first planted.The expansion accelerated further during the 1980s, when fast-growing eucalyptus species became part of government re-greening and plantation programmes. According to the review by Belachew and Minale, eucalyptus plantations now cover around 506,000 hectares of Ethiopia. For farmers, the trees can be particularly attractive because they provide marketable wood relatively quickly, while their cultivation can reduce reliance on natural forests for some wood products.That success, however, came with a growing environmental debate. Researchers and communities began reporting concerns about eucalyptus plantations near farmland and water sources, including reduced water availability, declining soil fertility and the displacement of native vegetation.Why the same trees can put pressure on springs and groundwaterThe concern is closely linked to the way eucalyptus grows. Fast-growing trees require substantial amounts of water, and eucalyptus has extensive root systems and high evapotranspiration rates that can draw moisture from the soil and groundwater. The 2025 review found that eucalyptus plantations can alter runoff, reduce soil moisture and decrease groundwater recharge.One finding highlighted in the review is particularly striking. In Ethiopia’s central highlands, converting cultivated land to eucalyptus plantations was associated with a 51.1% decrease in soil moisture and a 48.9% reduction in spring water flow. Research from the Koga watershed in the Amhara Region also found that eucalyptus plantations close to water sources could contribute to springs drying up completely.The effects can become even more pronounced during dry periods. In the Lake Tana Basin, researchers observed substantial groundwater fluctuations associated with eucalyptus plantations. The review reports that evapotranspiration from eucalyptus plantations during dry periods could reach 2,300 millimetres, around 1,400 millimetres more than in areas without eucalyptus.Scientists found that eucalyptus is not simply a “bad” treeThe water concerns do not mean eucalyptus has provided no environmental or economic benefits. In fact, its rapid growth is precisely what made it valuable to Ethiopia in the first place. The trees supply fuelwood and construction material, generate household income and can reduce pressure on native forests by providing an alternative source of wood.Research has also shown that the effects can depend heavily on location and management. A nine-year field study in Ethiopia’s Debre Mawi watershed, for example, found that expanding eucalyptus cover was associated with reductions in runoff and sediment concentrations. The researchers also noted a potential downside: eucalyptus could dry wells during the dry monsoon period, something they said required further investigation.This makes the question less about whether eucalyptus should exist in Ethiopia and more about where and how it should be planted. Planting large stands in water-scarce areas or close to springs can create very different consequences from planting trees in locations where their water demand does not threaten essential supplies.Ethiopia now faces a difficult choice over its fast-growing forestsA newer review published in 2026, ‘Environmental Impacts, Land-Use Trade-Offs, and Sustainable Management Pathways of Eucalyptus Plantation Expansion in Ethiopia,’ by Yohannes Gelaye and Kiros Getachew, reached a similar conclusion. It concluded that eucalyptus plantations generate economic benefits through timber, fuelwood, and household income but can also be a source of water shortage, soil degradation and loss of biodiversity.The authors call for better land use management rather than outright ban of eucalyptus. Some of the proposed methods include agroforestry, mixed planting, especially mixed with indigenous multipurpose trees such as Cordia africana, Faidherbia albida, and Acacia abyssinica. It aims at maximizing the economic benefits from the fast-growing tree without having adverse effects on the environment.This is a very surprising lesson from the Ethiopian experience on reforestation. The planting of trees may help deal with the shortage of timber and minimize deforestation of natural forests, but having more trees does not always mean having more water or healthy ecosystem. In landscapes where springs, groundwater and farmland depend on limited moisture, the species chosen, and where it is planted, can matter just as much as the number of trees put into the ground.Catch the latest World News and Live updates. Download the TOI app.