Achyranthes aspera is a common weed in fields: a full introduction to its characteristics and medicinal value

Achyranthes aspera (rough chaff flower) is an annual or perennial herb in the genus Achyranthes of the Amaranthaceae family. Also known as tu-niu-xi, dao-gou-cao and cu-mao-niu-xi, it is very common along field edges, roadsides and sunny grasslands in southern China. Its name sounds unfamiliar, but many people have actually seen it on country paths, they just cannot name it.

The plant usually grows from several tens of cm to about one meter tall, with four-angled stems bearing coarse hairs and opposite leaves that are mostly elliptical or obovate. In summer and autumn it sends up slender spike-like inflorescences, and the bracts of the small flowers bend outward to form tiny hooks that easily catch on people's clothing or animal fur. This is exactly where the names dao-kou-cao and dao-gou-cao come from.

In traditional folk use, Achyranthes aspera is mostly used as a whole-plant medicine, generally believed to clear heat and remove toxins, promote diuresis and reduce swelling. In some areas it is also used for sore, swollen throat and rheumatic discomfort. In a few places its tender stems and leaves are even gathered as a wild vegetable. It should be noted that before using it medicinally, it is best to consult a professional to avoid misidentification and misuse.

Achyranthes aspera is highly adaptable, tolerant of drought and poor soil, and prefers a sunny environment. It is not demanding about soil and is usually propagated by seed; after harvesting in summer and autumn, it can be washed, sun-dried and stored. It is easily confused with the related Achyranthes bidentata, which looks similar but is not used in exactly the same way. When harvesting, carefully distinguish the leaf, inflorescence and root characteristics to make sure the right species is used.