The correct spelling of the tree species commonly known as "Tree of Heaven" is Ailanthus altissima. The word "Ailanthus" is pronounced as /eɪˈlænθəs/ according to IPA phonetic transcription, with emphasis on the second syllable. "Altissima" is pronounced as /ælˈtɪsɪmə/ with emphasis on the first syllable. The word "ailanthus" comes from the Malayalam language and means "tree of the gods". Altissima is a Latin word meaning "tallest". This tree is known for its rapid growth and tolerant nature, making it a popular ornamental plant.
Ailanthus altissima, commonly known as the Tree of Heaven, is a fast-growing deciduous tree species native to northeastern and central China. It is categorized within the Simaroubaceae family of flowering plants. The name "Ailanthus" derives from the Moluccan term "ailanto," referring to the tree's resemblance to the vernacular species in the islands. "Altissima" translates to "very tall" in Latin, accurately describing its rapid vertical growth.
The Tree of Heaven is notable for its singular ability to thrive in diverse environments, adapting well to various soil types, pH levels, and climates ranging from temperate to subtropical. Mature specimens can reach heights of up to 80 feet (24 meters) with a distinctively straight trunk, smooth gray to brown bark, and light brown twigs. Its compound leaves consist of 10 to 40 oval-shaped leaflets with serrated margins, creating a graceful, fern-like appearance. In late spring or early summer, small, greenish-yellow flowers bloom in panicles which emit a distinctly unpleasant odor. Female trees bear clusters of winged seeds during autumn, called samaras, aiding in the species' wide dispersion.
While the Tree of Heaven is sometimes cultivated as an ornamental tree for its fast growth and attractive foliage, it is also considered an invasive species in many parts of the world, including North America, Europe, and Australia. Its aggressive root system and prolific seed production enable it to form dense thickets, outcompeting native species and disrupting ecosystems. Efforts are made to control its spread and limit its negative ecological impacts in affected areas.
The etymology of the word "Ailanthus altissima" is as follows:
The genus name "Ailanthus" derives from two Greek words. The first part, "aila", comes from the Greek word "ailao", which means "to swing" or "to move in the air". The second part, "anthos", means "flower". The name was coined by the Italian naturalist Filippo degli Albizzi in the 18th century to describe the tree's pendulous flower clusters.
The species name "altissima" comes from the Latin word "altus", meaning "high" or "tall". Therefore, "Ailanthus altissima" essentially translates to "the tallest or tallest-growing ailanthus tree". This name describes the tree's characteristic ability to grow to great heights.