Alnus spaethii Leaf (28/07/2012, kew Gardens, London)
Position: Full sun to light shade
Flowering period: Late winter
Soil: Moist, well drained
Eventual Height: 20m
Eventual Spread: 15m
Hardiness: 4a – 9a
Family: Betulaceae
Alnus spaethii is a medium sized, fast growing, deciduous tree with a wide pyramidal habit. Its mid/ dark green leaves are alternate, elliptic with serrulate margins and are up to 15cm long. Its bark is gray brown and slightly fissured. Its flowers are monoecious, the male being a hanging brown catkin. The female flowers are erect catkins which develop into cone like fruit which is up to 2.5cm long. Its roots form an association which enable them to fix nitrogen in the soil.
Alnus spaethii (28/07/2012, kew Gardens, London)
Alnus spaethii is commonly known as Spaeth’s Alder. Alnus spaethii is a hybrid between Alnus japonica and Alnus subcordata. Alnus spaethii is synonymous with Alnus x spaethii.
The etymological root of the binomial name for Alnus is the old Latin name for Alder trees. Spaethii is named after the location of the origin of this tree, Späth Arboretum, Berlin, Germany.
The landscape architect may find Alnus spaethii useful as an avenue or street tree. This tree is tolerant of urban pollution.
Ecologically, A. spaethii is attractive to some species of bird who eat its seed.
A. spaethii prefers moist, fertile, well-drained soils. It tolerates most pH of soil. It will tolerate wet soils.
Alnus spaethii Bark (28/07/2012, kew Gardens, London)
Alnus spaethii requires little maintenance.