Outstanding Features:
Dark green foliage, interesting small cones. Tolerance to wet soils.

Description:
Height: 15-50'
Width: 15-30'
Hardiness Zone: 3a

Alders are large shrubs or small to medium sized trees. They grow naturally in bogs or along stream banks where the soil is often quite wet. The European Alder (Alnus glutinosa) is a medium sized tree with a narrow pyramidal crown. It grows rapidly and often develops an irregular form. It can be somewhat short lived, especially if grown in dry, stressful sites. Foliage is clean, glossy dark green. The fruiting structure is about 1/2 inch long and resembles a small, dark brown pine cone. White Alder (Alnus incana) has a pyramidal to oval form and grows to 30-50' tall. It is very cold hardy and does well in wet sites. There are attractive cutleaf (`Laciniata') and weeping (`Pendula') forms of White Alder. Speckled Alder (Alnus rugosa) is native in boggy areas in the Great Lakes region. It is a large, upright growing shrub about 12-15' in height.

Requirements and Culture:
Prefers a moist, cool soil but tolerates drier soils. Full sun or partial shade. Good choice for difficult wet soil sites. Adaptable to a range of soil pH.

Limitations:
Alder psyllid and alder blight aphid can cause damage to the foliage. Plants are not widely available in nurseries.

Photo Credit: 1 E.Hasselkus; 2 MLA. Photo 1 is A. glutinosa, 2 is A. incana.

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