Black alder is a medium-sized, fast-growing, deciduous tree native to Europe, western Asia, and northern Africa, but has naturalized in other regions including the northeastern and central United States. It bears handsome, glossy, dark-green leaves from spring to fall, and its catkins provide mild interest in winter and early spring.
Requiring sun but thriving in most soils, it excels as a shade or screening tree in sites that are too damp or barren for other trees. It may be invasive in some situations. (Learn2Grow.com)
Not available for sale in Wisconsin.Genus - Alnus
|Seeds of alder requires 30-60 days cold moist stratification for best germination.
Stratification/ cold treatment: mix together equal amounts of sand and peat in a small container and moisten it with a little water. Mix the seeds in the medium and place it in the fridge at 40F (+2-+4C). Keep the medium moist throughout the stratification period.
After stratification sow on surface, keep moist at room temperature in the light place.