Alder, European Alder
Betulaceae (Birch family)
Origin: Italy, Corsica, 1920
of Los Angeles - Department of Public Works
Bureau of Street Services
Form - Deciduous. Vertical in youth, spreading with age. Grows to a height
of 40' with a 30' spread and pyramidal in habit.
Trunk - The balk is a gray green or greenish brown that changes to a soft
gray brown with age. Many lenticels are visible onthe branches.
Foliage - Heart shaped simple 4" leaves are borne alternately. Tops are
a glossy rich green. Paler undersides have distinctive rusty hair along
Flowers/fruit - The male flowers are 3 - 5" catkins while the female are
distinctly oval 1 -1 1/4" strobiles or cones, borne before the leaves
appear. The fruit is a 1" nutlet borne in the persistent strobiles which
remain on the tree in winter.
Significant pest problems are Armillaria root rot, aphids, and flatheaded
Sunset zones: 8, 9 and 14 - 24.
Clearances - Suitable for 8 - 12' parkways or 10 - 20' medians.
Good for streetsides, medians, parks and lawns.
Thrives in poor and dry soil and tolerant of acid or slightly alkaline
soils. Has invasive roots.