Polylepis woodland in central Peru. This stand of Polylepis trees is located in a ravine exposed to cloud circulation, hence its lush appearance.
Definition: Polylepis Woodlands are forest formations growing well above normal tree line at elevations over 5000 meters (16,304 feet). Polylepis woodlands are largely composed of Polylepis trees of the genus Polylepis, associated with grasses and scrubs. The genus Polylepis includes twenty-eight recognized shrub and tree species. Polylepis trees appear to be the highest naturally occurring arborescent angiosperm genus in the world.
Interior of a Polylepis Woodland showing the dead twigs and trunks with and multi-layer bark.
The appearance of Polylepis Woodlands and Trees
Polylepis trees are usually gnarled in shape and short, but in certain areas, some trees are 15–20 m (49-65 feet) tall and can reach 90 cm-thick trunks. The bark is thick, rough, and densely layered for protection against low temperatures. The name Polylepis is, in fact, derived from the Greek words “poly” (many) and “letis” (layers), referring to the shredding, multi-layered bark that is common to all species of the genus.
The foliage is evergreen, with dense small leaves. Trees often have large amounts of dead twigs hanging down from the underside of the canopy. Due to the harsh environment in which many species of Polylepis grow the growth of the tree’s stems and branches are generally contorted. This abnormal growth is often associated with windy, cold, and arid habitats.
Patches of Polylepis growing in more arid conditions at elevations ranging near 4500 meters (14,763 feet) of altitude.
Where are the Polylepis Woodlands found?
Polylepis forests exist primarily as small, widely isolated fragments surrounded by shrub and scrub communities, paramo habitat, and Puna Grasslands. Polylepis stands are usually restricted to steep, rocky slopes in sheltered valleys and more rarely in exposed windswept Andean plains.
Most species of Polylepis grow best at high elevations between 3500 and 5000 meters. However, there are occurrences of species at altitudes as low as 1800 meters.
Polylepis woodlands growing on a windswept hillside. The prevailing conditions here are arid and Polylepis trees have a scrub-like appearance.
Polylepis Woodlands are confined to the high tropical South American Andes Mountains, with the most abundant concentrations of Polylepis ranging from northern Venezuela to northern Chile and adjacent Argentina. The most extensive Polylepis tracts are found in the Cordillera Blanca and adjacent mountains of west-central Peru.
Polylepis woodlands provide protection against erosion and are habitats for a set of birds, some of which are almost restricted to life in this forest formations and currently face conservation challenges.
A stand of Polylepis trees growing in rather humid conditions in Abra Malaga, Cusco-Peru. Notice the forest floor covered in moss.
Since Polylepis woodlands occur in extremely high elevations, it has played an important role in the culture of various Andean human groups by providing building material and firewood. Polylepis woodlands are also affected by the destruction of seedlings by domesticated animals. Many of the pristine Polylepis woodlands are confined to “inaccessible” slopes. The trees are also used as decoration; planted in front of buildings and houses.
See more Neotropical bird habitats.
Antamina | Environment | Polylepis Conservation in South Conchucos.” Antamina. N.p., n.d. Web. 4 Nov. 2011.
Fjeldså, Jon; Kessler, Michael (1996). Engblom, Gunnar and; Driesch, Peter, eds. Conserving the Biological Diversity of Polylepis Woodlands of the Highland of Peru and Bolivia: A Contribution to Sustainable Natural Resource Management in the Andes. Copenhagen, Denmark: NORDECO.
Neotropical Birds: Ecology and Conservation. Stotz Douglas F., Fitzpatrick
John W., Parker Theodore A. III, and Moskovits Debra K. University of Chicago Press, 1996.