alerce, (species Fitzroya cupressoides), coniferous tree that is the only species of the genus Fitzroya, of the cypress family (Cupressaceae), native to southern Chile and southern Argentina. In the wild it grows to become one of the oldest and largest trees in the world. The alerce is thought to be a southern relative of the giant sequoia of North America. The oldest known alerce is believed to be about 4,000 years old. The alerce is often shrubby when raised in cultivation, but a native forest tree may reach a height of 45 m (about 150 feet) and attain a trunk diameter of more than 3 m (10 feet). The alerce’s small, narrow leaves are typically arranged in whorls of three and have distinct white bands running down their length. The tree’s reddish brown wood is lightweight and durable and is used for general construction.