The Myth That Eucalyptus Trees Deplete Soil Water—A Review

The increase in demand for timber and global eucalyptus cultivation has generated controversy regarding its potential impact on water resources, especially in regions with limited water availability, with the myth that “eucalyptus dries out the soil” being spread. In this regard, this review study addresses the factors that influence water consumption by eucalyptus, providing solutions to reduce, mitigate, or even avoid any impact on water resources at a given site. In this manuscript, the authors reviewed 200 works published from 1977 to 2024 to survey all information to confirm if the factual background allows someone to state if eucalyptus can deplete soil water. With a solid scientific basis, many research studies show that eucalyptus’ water demand is comparable to that of native forest species and crops worldwide and that species, age, edaphoclimatic conditions, and forest management practices mainly influence water consumption. On the other hand, it is a hasty conclusion that some eucalyptus species can contribute to reduced soil water. Effectively, without proper management, the environmental impacts of a eucalyptus plantation are the same as those of poorly managed crops. Indeed, if cultivated with proper agroclimatic zoning and correct management practices, the growth of eucalyptus culture is an environmentally correct activity. By adopting measures such as maintaining sufficient native forest cover to ensure ecosystem services, cultivation based on zoning maps, and considering local specificities (e.g., deeper, sandier soils are preferable), selection of species appropriate to the carrying capacity of each region, adoption of lower planting densities, and reduced rotation, eucalyptus cultivation will not negatively affect water resources. Sustainable eucalyptus cultivation has several economic and environmental benefits, in addition to positive social impacts on surrounding communities in terms of employment and family income, and its sustainable management can guarantee its viability, demystifying the idea that eucalyptus trees cause water scarcity. The works reviewed herein demonstrated no solid ground to sustain the eucalyptus’ water depletion myth.