Achyranthes aspera L.

Code

ACYAS

Growth form

broadleaf

Biological cycle

annual

Habitat

terrestrial

China: Achyranthes aspera flowers from June to August and fruits in October.
Nicaragua: Achyranthes aspera flowers and fruits from July to March.

Northern Cameroon: Achyranthes aspera is a weed growing at the middle and especially at the end of the cropping season. Germination occurs in June, regardless of plowing, when rains are abundant and regular. This phase of germination is very short (1 to 2 weeks). In unweeded fields, flowering starts late August and fruiting in October, a full cycle of four months. In contrast, in crops regularly weeded and mounded, a new short germination phase can occur in September, after the last cultural operation. The development cycle length is reduced to one month, from emergence to fruiting. The flowering of this species is induced by the reduction of the length of day. The plant disappears after beginning of the dry season (November-December).
Mayotte: It is an annual plant which grows all year round.
New Caledonia: Germination occurs after the first rains, growth is then fast enough to flowering that occurs in 1 or 2 months. Fruiting occurs until cool season before the plant dies.
West Indies: Achyranthes aspera flowers and fruits all year round.

Commonly found in disturbed areas. Prefers moist soil but can grow well in dry areas.

Northern Cameroon: Achyranthes aspera develops from the Sudanese to Sahelo-Sudanese regions. It is present in 20-30% of cultivated fields. In Sudano-Sahelian region, this species develops only on soils with high water retention (fersialitic soils) or with a water table near the surface (alluvial, waterlogged soils). In the Sudanese region, it develops over a wider range of soils, although it is very rare on ferruginous soils with degraded sandy surface horizon.
Central Africa: Achyranthes aspera grows in humid and shady places, frequent in swamps, mud of the water's edge, but also ubiquitous (savannah, sclerophyllous forest), thanks to a remarkable adaptability and to the process of dissemination (passive zoochory) of its fruits; it constitutes an invasive weed of the edge of roads, inhabited places, crops, pastures, fallow lands, following man even in dry stations, up to 1,600 m of altitude in the mountains of Kivu.
Comoros: The species is present in all the islands, both in humid and dry environments, up to 400 m altitude.
Madagascar: A. aspera is a fairly common species of rainfed crops in warm areas (low and medium altitudes), or on relatively rich soils  in recently cleared land plots and poorly maintained.
Mauritius: A. aspera is a ruderal species in disturbed areas and along roadsides, and also a weed of crops. It is more common in the northern part of the island.
Mayotte: Achyranthes aspera is a weed that is very present in ylang-tree plots and in forage crops. It can be found in fruit and food crops. It is mainly present in the dry zone of the south of the island, but it can also be found in the north.
New Caledonia: A. aspera is a weed of fallow land, disturbed areas and pastures. It particularly enjoys moist soil but grows well in dry soils of the coast and back over the islets.
Reunion: The species is common in Reunion island, occurring evenly from 0-900 m altitude. It grows particularly along rivers, in wet places, in disturbed habitats and, in general, as ruderal species and weed in irrigated plots of the West Coast.
Seychelles: This species is observed from coastal areas to higher altitudes.
West Indies: Achyranthes aspera is typically a very ubiquitous ruderal species, present from 0 to 1000 m altitude.

Local weediness

Northern Cameroon: A. aspera is a species characteristic of non-intensified or less intensified crops including traditional food crops (sorghum, groundnut). It is common in the recently cleared land in crops where pre-emergence herbicides are not applied and fertilizers less used. It is absent from older, intensively cultivated plots, receiving herbicides regularly. But this type of cropping system is important in the Sudanese region, which explains the low frequency of A. aspera. In addition, this species is easily removed by repeated weeding.

Comoros: A. aspera is a weed present in cassava plantations and at the border of all crop fields.

Madagascar: A. aspera is a common species in field edges and abandoned plots. It is less intrusive and rarely interfering. In the crop, it is relatively less frequent but sometimes locally abundant and harmful to crops that have a rather long cycle such as cotton, cassava. Due to its late vegetative development, it hinders harvesting operations (cotton, corn, peanuts, cassava).

Mauritius: A. aspera is an occasional weed in cultivated fields,  with a low competitveness.

New Caledonia: A. aspera is an introduced species: it was observed from the late 18th century. This is now a common species throughout the territory at rather low to medium altitudes. A. aspera is not an invasive species in pastures but its development is often related to overgrazing, it constitutes with other minor weeds a set of non or less patatable species whose abundance is involved in the degradation of pastures and decreases the production of forage species.

Reunion: A. aspera is present in 13% of surveys with an average cover of 7-15%. Present in 17% of surveys in sugarcane and 3% in vegetable crops, it does not constitute any particular problem when the weeds is well controlled. Conversely,  its cover can reach from 30 to 50% due to poor weed control.

Seychelles: A. aspera is a weed of crops, cultivated areas and fallow lands.

Food: Leaves of Achyranthes aspera can be eaten.
Medicinal: Achyranthes aspera is traditionally used to treat chest pain and stomach ache. In Chad, the boiled leaves are used against scabies (Yambata) and provide a remedy for headaches (Dundusana); incinerated after boiling, they yield cooking salt (Abok). In India, it is used to prepare potash and is said to be a remedy for scorpion stings.
Other: Fruits are eaten by birds.

Local Management

Madagascar: A. aspera is easily controlled by uprooting. Little information is available on its sensitivity to herbicides: A. aspera is well managed by postemergence 2,4-D or glyphosate. A. aspera is well controlled by a cover crop.

New Caledonia: In pastures, it is appropriate to prevent germination and propagation of A. aspera , an annual species, to a maxmum by maintaining a dense grassy cover. Livestock having stayed in infested areas must be quarantined. Isolated plants can be easily uprooted by hand with gloves. For established on stands, overgrazing of infested areas at an early stage of growth can contribute to weed out this species. Slashing only causes regrowth of the plant and can contribute to its spread, if carried to fruition. So we complement it with a herbicide spraying in targeted on isolated plots or in full if more diffuse infestation. Preference will be given to conventional herbicides such as 2,4-D, selective to grasses.

Herbarium pictures ReCOLNAT: https://explore.recolnat.org/search/botanique/simplequery=Achyranthes%2520aspera