Hedera helix (common ivy)

description: evergreen vine

place of origin: Europe, western Asia, northern Africa

urban habitat: thrives in neglected landscapes, fields, climbing trees, sides of buildings, fences; spreads by small root-like structures which exude a sticky substances that allows it to adhere to various surfaces; grows along ground in its juvenile phase, climbing into tree canopies in its adult vertical phase covering branches and often killing trees by blocking light; can survive for decades.

ecological function: shade tolerant, disturbance-adapted colonizer; food and habitat for wildlife; has been shown to be effective at improving air quality by removing common indoor pollutants and by trapping atmospheric particulate matter outdoors.

history: Hedera helix is often confused with the related species Hedera hibernica (Irish Ivy) with which it hybridizes in the wild, and look extremely similar, being only definitively distinguishable using molecular markers, or by examining the trichomes (hairs) on the leaf surface. Recent studies have shown that of the two species, Hedera hibernica is more aggressive and therefore may be more prevalent in the US. Hedera helix was introduced from Europe in North America by early settlers for ornamental purposes, first documented in Virginia around 1800. It continues to be planted widely in the US as a ground cover. It is found throughout the eastern states to Florida, in many Midwestern states, Texas, and in California, Oregon, Washington, Arizona and is considered invasive in most US states. It has been introduced to South Africa, India, Australia, New Zealand, Brazil and Mexico. In European folk remedies, its leaves and berries were taken orally as an expectorant, as treatment for gout and rheumatic pain, and was used as a topical agent for its antifungal and antimicrobial properties. Recent research has shown that the leaves contain the compound 'emetine', which is an amoebicidal alkaloid, and also triterpene saponins, which are effective against liver flukes, molluscs, internal parasites and fungal infections. Hedera helix has other uses: a yellow and a brown dye can be obtained from its twigs and an extract of the leaves has been used to restore black fabrics and as a hair rinse to darken the hair. The leaves boiled with soda act as a soap substitute for washing clothes. Its woody stem can be used to create engraving blocks and its younger vines used to make paper.