Amaranthus retroflexus (red-root amaranth, "Aogeito")

Japanese name: アオゲイトウ （青鶏頭）
Scientific name: Amaranthus retroflexus

[Overview]
An annual 0.5–1 m tall.
The stem is erect and branched.
Leaves are simple and alternate, rhombic-ovate, 5–10 cm long; the upper surface is almost hairless, and the veins on the underside have soft hairs.
The leaf margin is entire.
The inflorescences arise from the leaf axils; those in the upper part of the stem branch densely, and the flower spike at the stem tip is short and dense.
The flowers are male or female, with 5 spatulate tepals that have a short awn at the tip.
The bracts are hard and end in a long awn.
The fruit is a utricle.

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