An alerce tree (right) grows amidst a grove of "ten" or cypress guaitecas (pilgerodendron uviferum), a rare coniferous tree that loves rainy places and prefers peat bogs. The alerce, also known as Patagonian cypress or lahuén (the name given by the Araucanian Indians), is endangered and is thought to be a southern relative of the giant sequoia of North America. It is among the oldest living beings on earth, and has greater longevity than either the coast redwood or the giant sequoia of California. A 3,631-year-old alerce in Chile has the second-greatest fully verified age recorded for any living tree (second only to California's bristlecone pine).

The alerce can reach 14 feet in diameter and 150 feet in height. Charles Darwain, who saw alerce trees reaching 130 feet in circumference, bestowed the generic name Fitzroya cupressoides in honor of Robert Fitzroy, captain of the H.M.S. Beagle.

These extremely slow-growing trees grow in rainy places and are found only in remote areas of the North Andean-Patagonian Regional Eco-Corridor. They contain resins that resist decomposition, making them especially valuable for exterior construction (for such materials as shingles and decks). As a result of this and other characteristics, such as their straight grain, alerce trees suffer from overcutting, which spirals into even more devastation because of their low reproductive rate.