Euonymus fortunei, the spindle, Fortune's spindle, winter creeper or wintercreeper, is a species of flowering plant in the family Celastraceae, native to east Asia, including China, Korea, the Philippines and Japan. E. fortunei is highly invasive and damaging in the United States, causing the death of trees and forest in urban areas.[1]
It was first described in 1863 as Elaeodendron fortunei by Nikolai Turczaninow,[2] who named it in honour of the Scottish botanist and plant explorer Robert Fortune. It was transferred to the genus, Euonymus, in 1933 by Heinrich von Handel-Mazzetti.[3]
It is an evergreen shrub which grows as a vine if provided with support. As such it grows to 20m (70feet), climbing by means of small rootlets on the stems, similar to ivy (an example of convergent evolution, as the two species are not related). Like ivy, it also has a sterile non-flowering juvenile climbing or creeping phase, which on reaching high enough into the crowns of trees to get more light, develops into an adult, flowering phase without climbing rootlets.
The leaves are arranged in opposite pairs, elliptic to elliptic-ovate, 2–6 cm long and 1–3 cm broad, with finely serrated margins. The flowers are inconspicuous, 5 mm in diameter, with four small greenish-yellow petals. The fruit is a smooth, dehiscent capsule with reddish arils.[4]
There are two or three varieties:
It has an extensive native range, including many parts of China (from sea level to 3400 m elevation), India, Indonesia, Japan, Korea, Laos, Myanmar, Philippines, Thailand, and Vietnam.[5] It has also been introduced to North America as an ornamental, and is considered an invasive species throughout much of the Eastern United States.[6] [7] It resembles Euonymus japonicus, which is also widely cultivated but is a shrub, without climbing roots.[8] It also is related to a variety of similar species, including Euonymus theifolius, or Euonymus vagans and also a number of named "species" which are found only in cultivation and better treated as cultivars. Its habitats include woodlands, scrub, and forests.[9]
Euonymus fortunei is widely cultivated as an ornamental plant, with numerous cultivars selected for such traits as yellow, variegated and slow, dwarfed growth. It is used as a groundcover or a vine to climb walls and trees. The following cultivars have gained the Royal Horticultural Society's Award of Garden Merit:[10]
Plants propagated from mature flowering stems (formerly sometimes named "f. carrierei") always grow as non-climbing shrubs. Some popular cultivars such as 'Moon Shadow' are shrub forms.
Most of the cultivated plants belong to var. radicans (Huxley 1992). It is generally considered cold hardy in USDA zones 5 to 9, and is considered an invasive species in some parts of the world, notably the eastern United States[16] [17] and Canada.[18]