
Appearance
"B. davidii" is a vigorous shrub with an arching habit, growing to 5 m in height. The pale brown bark becomes deeply fissured with age. The branches are quadrangular in section, the younger shoots covered in a dense indumentum.The opposite lanceolate leaves are 7–13 cm long, tomentose beneath when young. The honey-scented lilac to purple inflorescences are terminal panicles, < 20 cm long. Flowers are perfect, hence are hermaphrodite rather than monoecious as is often incorrectly stated.

Naming
"Buddleja davidii" has been classified as an invasive species in many countries in temperate regions, including the United Kingdom and New Zealand. It is naturalized in Australia and in most cities of central and southern Europe, where it can spread on open lands and in gardens.Within the United States, it is widely established as an escape from cultivation, and classified as a noxious weed by the states of Oregon and Washington.
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