Japanese name: センダングサ（栴檀草） Scientific name:Bidens biternata var. biternata
[Overview]
An annual 30–150 cm tall, found along roadsides, in vacant lots, and at the edges of ditches.
The stem is erect, branched, slightly 4-ridged, and covered with curled hairs.
The leaves are 1–2-pinnately compound, 9–15 cm long, opposite on the lower part of the stem and alternate on the upper part, and consist of 5–7 leaflets.
Both sides of the leaves are densely hairy, and the terminal leaflet is ovate.
The leaf margins have teeth.
Flower heads are borne at the branch tips on the upper part of the stem, each with 0–5 yellow ray florets.
The outer involucral bracts are linear, 8–10 in number.
The fruit is an achene with 3–4 awns (spines).
The awns have small downward-pointing barbs.
