Clethra arborea in the second week of October 1999 in Madeira

''Clethra arborea'', commonly known as the lily-of-the-valley-tree, is a flowering plant in the genus ''

Clethra ''Clethra'' is a genus of flowering shrubs or small trees described as a genus by Linnaeus in 1753.Macaronesia where it is native to

Madeira ) , anthem = ( en, "Anthem of the Autonomous Region of Madeira") , song_type = Regional anthem , image_map=EU-Portugal_with_Madeira_circled.svg , map_alt=Location of Madeira , map_caption=Location of Madeira , subdivision_type=Sovereign st ...

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

in the

Canary Islands The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...

, and considered an introduced species in the Azores. In Madeira its natural habitat is laurisilva forest.

Description

It is an evergreen narrowly upright

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

or small tree, growing to about 6 m tall and 4 m wide. The foliage is dense and glossy, with the leaves up to 7–10 cm long. The flowers are small, white and fragrant, similar in appearance to those of lily of the valley, hence the

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

. (Lily of the valley is not closely related, being a monocotyledon.) The flowers are grouped in terminal

panicle A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are of ...

s and bloom in early to mid summer.Cool Exotics. The plant is toxic to humans; it contains

andromedotoxin Grayanotoxins are a group of closely related neurotoxins named after '' Leucothoe grayana'', a plant native to Japan originally named for 19th century American botanist Asa Gray. Grayanotoxin I (grayanotaxane-3,5,6,10,14,16-hexol 14-acetate) is als ...

which may cause diarrhea and even sudden death.The Free Dictionary.

Cultivation

The tree prefers moist, acidic and well-drained soils, disliking alkaline soils. It is sensitive to

frost Frost is a thin layer of ice on a solid surface, which forms from water vapor in an above-freezing atmosphere coming in contact with a solid surface whose temperature is below freezing, and resulting in a phase change from water vapor (a gas) ...

and likely to die if the temperature falls below −3 °C. It is propagated by seeds, cuttings and air-layering.

References

Notes

Sources

* * arborea Flora of Madeira Flora of the Azores Endemic flora of Macaronesia Plants described in 1789 {{Ericales-stub