"Alder is the common name of a genus of flowering plants, Alnus, belonging to the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes." - (en.wikipedia.org 17.09.2020)
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