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Birch family🌳
Betulaceae
カバノキ科
A family including birches, alders, and hazels. Distributed in temperate to boreal regions of the Northern Hemisphere, characterized by white bark and long catkin inflorescences. Alders form symbiotic associations with nitrogen-fixing Frankia bacteria and are pioneer species on wetlands and disturbed sites.
Key Characteristics
- ●Catkins (long, pendulous inflorescences)
- ●Wind-pollinated
- ●Fruit is a small winged nutlet
- ●Many species have peeling white bark
Morphological Traits
A family may include species with different trait values — multiple values indicate the range within the family.
Leaf arrangement
Alternate
Leaf type
Simple
Venation
Pinnate
Leaf margin
Serrate / Dentate
Growth form
Shrub / Tree
Evergreen/Deciduous
Deciduous
Leaf dissection
Undivided
Stipules
Present
Petal count
3 petals / 4 petals / No petals
Ovary position
Superior
Stamen count
1-2 / 3-4 / 5 / 6
Plant sex
Monoecious
Phylogenetic Position
Angiosperms > Eudicots > Fagales > Betulaceae
Divergence Era
Late Cretaceous to Paleogene
Representative Genera
Related Evolution Events
- ・Contributed to the formation of cool-temperate forests in the Northern Hemisphere