Resilient andean trees show promise in long-term forest restoration efforts

High in the Andes Mountains, an extraordinary species of tree is proving that nature’s toughest survivors can also be conservation success stories. Polylepis trees, known locally as queñual, represent some of the world’s most resilient forest ecosystems, thriving at altitudes up to 16,400 feet where they endure extreme conditions that would kill most other vegetation.

These remarkable trees, with their distinctive gnarled trunks and twisted branches, have adapted to survive intense solar radiation, freezing nighttime temperatures, powerful winds, and seasonal droughts. Despite their stunted appearance, the 28 species of Polylepis trees and shrubs serve crucial ecological functions across the high Andes. Their small, waxy leaves act like natural water collectors, capturing moisture from fog and channeling it into mountain soils that feed streams and rivers flowing to coastal regions. The trees also prevent soil erosion and reduce flood risks while providing local communities with firewood and medicinal plants.

However, centuries of livestock grazing have decimated these unique woodlands, reducing them to just 2% of their historic range in Peru and 10% in Bolivia. The trees now survive primarily in the most inaccessible mountain locations—steep slopes, boulder fields, and sheltered ravines where cattle and sheep cannot reach.

Recent research by environmental scientist Tina Christmann from Southampton University and other restoration groups suggests that decades-long efforts to restore these Andean forests are showing promising results, offering hope for recovering these critical high-altitude ecosystems that play outsized roles in regional water cycles and mountain stability.