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Tall Goldenrod🌼
Solidago altissima
セイタカアワダチソウ
An introduced species from North America. Forms dense colonies with yellow flower spikes in autumn. Known as an invasive alien species, forming large stands along riverbanks and wastelands. Once mistakenly blamed for hay fever, but it is insect-pollinated and not a cause of pollen allergies.
Identification Points
- ✓Yellow paniculate inflorescences arch outward in autumn
- ✓Stems are tall (over 1-2 m) and upright
- ✓Leaves are narrow and alternate
- ✓Forms large colonies on riverbanks and wastelands
Habitat
Riverbanks, wastelands, vacant lots, roadsides
Season
October to November (flowers)
Morphological TraitsAI-estimated, needs verification
Leaf arrangement
Alternate
Leaf type
Simple
Venation
Pinnate
Leaf margin
Serrate
Leaf shape
Ovate
Growth form
Herb
Petal count
5 petals
Petal fusion
Fused
Flower color
Yellow
Flowering season
Autumn
Habitat
Wetland
Ovary position
Inferior
Stamen count
1-2
Phylogenetic Positionキク科 →
Phylogenetic Position
Angiosperms > Eudicots > Core eudicots > Asterales > Asteraceae
Divergence Era
Late Cretaceous to Paleogene (approx. 80–70 million years ago)
Sources & References
AI-generated, needs verification