Japanese name: スイバ（酸葉） Scientific name:Rumex acetosa
[Overview]
A perennial 30–100 cm tall, found on embankments, rice-field ridges, roadsides and similar places.
It has a thick, short, yellow underground stem.
The stem is cylindrical, tinged with red, and has lengthwise ridges.
There are basal leaves and stem leaves.
The leaves are oblong-lanceolate, 10 cm long; basal leaves and leaves on the lower part of the stem have petioles.
Leaves on the upper part of the stem are sessile or clasp the stem at the base.
It is dioecious.
Conical inflorescences at the stem tips bear dense small flowers.
There is no corolla.
The female inflorescence looks red because the stigmas of the female flowers are red.
The male inflorescence is pale yellow.
The fruit is an achene enclosed in the wing-like enlarged calyx.
[Uses]
In Japan the young leaves can be eaten as a wild vegetable.
In Europe it is used as a vegetable.
The roots and flowers are used medicinally.
The leaves are also made into herbal tea.
It contains oxalic acid, so eating large amounts may cause poisoning and caution is needed.
