Distribution map of the Green Alder Alnus alnobetula (syn. Alnus viridis) complex.
Subspecies[1]: 
     Alnus alnobetula subsp. alnobetula
     Alnus alnobetula subsp. crispa
     Alnus alnobetula subsp. fruticosa
     Alnus alnobetula subsp. sinuata
     Alnus alnobetula subsp. suaveolens
Caudullo, G., Welk, E., San-Miguel-Ayanz, J., 2017. Chorological maps for the main European woody species. Data in Brief 12, 662-666. DOI: 10.1016/j.dib.2017.05.007
Data: https://doi.org/10.6084/m9.figshare.5100730
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Giovanni Caudullo