Aerial root

"Pneumatophore" redirects here. For the air bladder of the Portuguese Man of War, see Portuguese Man o' War.
The grey mangrove (Avicennia marina)'s pneumatophorous aerial roots
A Heptapleurum arboricola indoor bonsai soon after branch pruning to show extensive aerial roots.
Banyan tree of undetermined species in Fort Myers, Florida
European beech with aerial roots in a wet Scottish Glen.
Hybrid elm cultivar with aerial roots, Edinburgh
Indian banyan tree in Kodungallur Temple, Kerala, India

Aerial roots are roots growing above the ground. They are often adventitious, i.e. formed from nonroot tissue. They are found in diverse plant species, including epiphytes such as orchids (Orchidaceae), tropical coastal swamp trees such as mangroves, banyan figs (Ficus subg. Urostigma), the warm-temperate rainforest rata (Metrosideros robusta), and pohutukawa trees of New Zealand (Metrosideros excelsa). Vines such as common ivy (Hedera helix) and poison ivy (Toxicodendron radicans) also have aerial roots.