Home Flora of Missouri
Home
Name Search
Families
Volumes
Hedera helix L. Search in The Plant ListSearch in IPNISearch in Australian Plant Name IndexSearch in NYBG Virtual HerbariumSearch in Muséum national d'Histoire naturelleSearch in Type Specimen Register of the U.S. National HerbariumSearch in Virtual Herbaria AustriaSearch in JSTOR Plant ScienceSearch in SEINetSearch in African Plants Database at Geneva Botanical GardenAfrican Plants, Senckenberg Photo GallerySearch in Flora do Brasil 2020Search in Reflora - Virtual HerbariumSearch in Living Collections Decrease font Increase font Restore font
 

Published In: Species Plantarum 1: 202. 1753. (1 May 1753) (Sp. Pl.) Name publication detailView in BotanicusView in Biodiversity Heritage Library
 

Project Name Data (Last Modified On 8/4/2017)
Acceptance : Accepted
Project Data     (Last Modified On 7/9/2009)
Status: Introduced

 

Export To PDF Export To Word

1. Hedera helix L. (English ivy)

Pl. 219 c; Map 910

Plants lianas, less commonly bushy shrubs. Stems to 20 m or more long, the climbing phase sparsely branched, becoming anchored by adventitious roots, the young stems densely stellate-pubescent. Leaves alternate in the climbing phase, sometimes opposite or whorled in the shrubby phase, evergreen, simple, the blade 2–12 cm long, ovate to nearly orbicular, entire or more commonly palmately 3- or 5-lobed, rounded to pointed at the tip, rounded to cordate at the base, the margins entire or slightly wavy, leathery, dark green on the upper surface, whitened along the veins, yellowish green on the undersurface, stellate-pubescent when young, becoming glabrous or nearly so at maturity. Inflorescences thus far not produced in Missouri material, solitary from the branch tips or in a short raceme, consisting of 1 or more simple umbels each with a stalk 2–8 cm long. Sepals 5 minute teeth or a low, 5-toothed crown. Petals 2.5–3.5 mm long, elliptic-ovate, greenish yellow. Style 1. Fruits 7–10 mm long, globose or somewhat obovoid, black, with 3–5 stones. 2n=48. July–October.

Introduced, uncommon, known thus far from Madison County and St. Louis (native of Europe; widely cultivated, escaping sporadically in the eastern U.S.). Mesic upland forests; also old homesites and railroads.

English ivy is commonly cultivated as an evergreen ground cover or trellis plant, sometimes also to hide fences and old walls. The heavy growth and the adventitious rootlets by which the plant becomes fastened as it climbs can damage trees, wooden structures, and mortared walls. Plants persist for many years after abandonment and can also occasionally spread from stem pieces that become rooted. The creeping/climbing phase does not produce flowers and generally has lobed leaves, but older plants may sometimes produce stiff, branched stems forming bushy shrubs, which become fertile at the branch tips and have unlobed leaves (Robbins, 1957). This shrubby phase is not known outside cultivation in Missouri. Steyermark (1963) noted that all parts of the plant are poisonous to humans if eaten and can cause dermatitis when handled in some people.

A number of infraspecific taxa have been described for H. helix; the few specimens from outside cultivation in Missouri appear to represent the diploid var. helix (2n=48), which is characterized by having whitened veins on the upper leaf surface. However, the tetraploid var. hibernica G. Kirchn. (2n=96), which is known as Irish ivy or Atlantic ivy and differs most notably in its green veins (Lawrence, 1956; McAllister and Rutherford, 1990), also is cultivated widely and may eventually be recorded as an escape in Missouri. Numerous cultivars are sold commercially as well.

 


 

 
 
© 2020 Missouri Botanical Garden - 4344 Shaw Boulevard - Saint Louis, Missouri 63110