Sicyos angulatus ("Arechiuri")

Japanese name: アレチウリ
Scientific name: Sicyos angulatus

[Overview]
A climbing annual found in sunny vacant lots, riverbeds, roadsides and similar places.
The vines are covered with coarse hairs and, clinging to other plants with tendrils that fork into three, grow to several to over ten meters long.
The leaves are alternate and round-heart-shaped with 5–7 shallow lobes, and the lobes are pointed.
Both surfaces of the leaves are rough.
The petioles are long.
There are male and female flowers, both borne in inflorescences arising from the leaf axils.
The male flowers are borne in corymb-like inflorescences 10–15 cm long; they are yellowish white and 1 cm across, and the stamens are fused into a single mass.
The female flowers are borne in large numbers in short head-like inflorescences; they are pale green and 0.6 cm across.
The flower stalks bear sparse glandular hairs.
The fruit is a long-ovate to elliptic berry, borne in clusters shaped like konpeito (star-shaped sugar candy), and densely covered with soft hairs and prickles.
Each fruit contains 1 seed.

[History]
It was identified in 1952 at Shimizu Port, Shizuoka, and has become widely naturalized from the Tohoku region southward.

[Notes]
It is designated a "Specified Invasive Alien Species" under the Invasive Alien Species Act.

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