Cyperus odoratus (fragrant flatsedge, "Kingayatsuri")

Japanese name: キンガヤツリ （金蚊帳吊）
Scientific name: Cyperus odoratus

[Overview]
An annual 20–70 cm tall, found in damp places such as wetlands and the banks between rice paddies.
The stems are thick and triangular in cross section.
The leaves grow near the base; they are linear, 0.5–0.8 cm wide, and the sheath at the base is tinged with red.
At the stem tip it produces 5–8 branches bearing spikelets, and the base has several long leaf-like bracts.
The spikelets are golden-tinged, linear, about 1–2 cm long and 0.1 cm wide, and are borne in large numbers spreading out from the axis of the inflorescence.
The scales are arranged in 2 rows; they are broadly elliptic, about 3 mm long, slightly blunt at the tip, with a green midrib and a rounded back.
The fruit is obovate with 3 ridges, 1.2–1.5 mm long and 0.5 mm wide.
Even when the fruit ripens, the scales remain in contact with one another, and the axis of the spikelet becomes a cork-like wing that encloses the fruit.
There is a joint between the base of the spikelet and each scale, and when the fruit ripens the spikelet breaks apart and falls.

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