Himalayan balsam
(Impatiens glandulifera)
An alien invasive species and noxious weed, introduced in the 19thC as a garden ornamental and now widespread throughout Britain, especially beside water and in other damp areas. Himalayan balsam is an annual (the tallest in Britain, growing up to 3m). The seeds of Himalayan balsam are released explosively and are projected up to 7m; they can also be carried in water.
This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
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