Euphorbia hirta L.

Code

EPHHI

Growth form

broadleaf

Biological cycle

annual

Habitat

terrestrial

Northern Cameroon: E. hirta is able to grow and produce seeds throughout the year, when the humid conditions allows it. In cultivated plot, it is very common in early cycle (43% of the plots) and can be relatively abundant. After weeding in mid-cycle, its frequency decreases sharply (28% of the plots) as well as its abundance. However, in the end of cycle, its frequency increases again around 41%, but its abundance remains low. The germination begins in May, during the first heavy rainfall. The first flowering can then intervene very quickly (15 days). These emergences can be easily removed by plowing or weeding, but a new short germination phase takes place after each cultural operation. It can take place until September or later in the case of delayed maintenance. Flowering occurs 2 to 4 weeks after emergence, followed two weeks later by fruiting. The plants disappear after drying in late November.
Mayotte: E. hirta flowers and fruits all year round.
New Caledonia: The plant is able to grow and to produce seeds all the year in condition of sufficient moisture. The germination takes place with the first abundant rains. Flowering occurs very quickly within 15 to 30 days, followed by fruiting 15 days later. The plant dies in dry season.

Northern Cameroon: Euphorbia hirta is a heliophilic species encountered as ruderal on roadsides and as a weed of crops. It is globally present in 40% of the plots, but its frequency increases with rainfall, 20% in Sudano-Sahelian zone (600-800 mm annual rainfall) to 48% in Sudan region (1200-1500 mm of rainfall annual). It has a strong preference for sandy or gravelly soils, like ferruginous soils; it is less frequent in planosol and on more clayey, fersialitic soil and very rare on vertisol and hydromorphic soil because of their very high clay content and their clogging. It is absent from the recently cleared plots and appears only after 4 or 5 years of cultivation. It is part of the floristic of Commelina benghalensis corresponding to a flora of ancient plots, slightly or intensively cultivated (mechanized tillage, fertilizer and repeated use of pre-emergence herbicide on cotton).
Comoros: cosmopolitan, pantropical and ruderal species that grows very quickly. It is present on all three islands, along the roads, in the courtyards of the houses and cultivated fields up to 700 m altitude.
French Guiana: Very common species in ruderal vegetation, gardens and cultivated plots.
Madagascar: Species cosmopolitan and widespread throughout the island especially in areas of low and medium altitude.
Mauritius: common weed in crops, fallow land, vacant land, especially near the coasts and on outcrops of coral rock.
Mayotte: E. hirta is a very common exotic species, naturalized in a wide range of open degraded environments, villages, crops, roadsides, rocks. It is particularly present in the center and the south of the island.
New Caledonia: It grows in very sunny environment and can be found on dry places as well as in humid areas. However, it is not present at altitude and on mining soils. It prefers very much sandy or gravel soils.
Reunion: E. hirta is an invasive plant which spreads very quickly. It is a species occurring in very sunny areas that occurs both on dry land and in the humid areas. However, it is not present at altitude. It clearly prefers sandy soils or gravelly.
Seychelles: Species present in all soil types, at all altitudes.
West Indies: Euphorbia hirta is a indigenous species. It occupies both urban and rural environments. It is very common in cultivated plots and is present on both sandy and clay soils. It establishes and maintains itself in plots with low tillage frequency.

Local harmfulness
 
Benin: rare but abundant when present.
Comoros: E. hirta is a very common weed in vegetable crops and in cassava culture.
French Guiana: It is occasionally abundant in fruit crops (especially banana). It is also observed on the edges of vegetable plots but very rarely in cultivation.
India : Invasive, however without harmfulness, this species is very frequent in the fields of rice, corn, sugarcane, peanuts and potatoes.
Madagascar: very common species but with rather limited dominance due to its relatively small size. It can be harmful in certain crops such as groundnuts, vouandzou or upland rice.
Mali: rare but abundant when present.
Mauritius: very common weed in crops, but has a low harmfulness in general.
Mayotte: E. hirta is a very frequent weed, present in 34% of cultivated plots. It is abundant in pineapple crops. It is also frequent in vegetable crops and can be found in food crops.
New Caledonia: Introduced in New Caledonia in the middle of the 19th century, it can be invasive because of the development of sometimes very dense stands, but it remains without significant harmfulness in pastures.
Reunion: A weed of common culture, though without great harmfulness. The species is very common in young sugar cane fields.
Seychelles: Species that could become a serious weed in vegetable and ornamental crops.
Tanzania: Frequent but not abundant.
Uganda: Frequent and abundant.
West Indies: Euphorbia hirta is a very common weed but not very harmful to crops. It is rarely abundant and easily controlled by weed control techniques.

Medicinal: The latex of Euphorbia hirta is used to heal small open wounds and cuts. The extracts of Euphorbia hirta have anti-anaphylactic effects (avoid allergic reactions). In the Comoros, the whole plant tea is used to treat diarrhoeal disorders. The leaves and latex are used against intestinal diseases, ulcers and bronchitis, and the latex for conjunctivitis.

Other: It may have slightly poisonous properties and is useless as fodder for livestock.

Global control
 
For weeding Advice of broadleaf annual weeds of irrigated rice and lowland in Africa, visit: http://portal.wiktrop.org/document/show/19

Local control

New Caledonia: Euphorbia hirta is not in itself an invasive species of pastures but it participates in the degradation of a pasture by adding its abundance to that of other non palatable species. Moreover, its toxicity deserves to be identified and controlled from the first appearances. A simple mechanical action remains inefficient and temporary because the deep root system causes regrowth. It will therefore have to be combined with a selective grass herbicide application (2,4-D) in view of the disseminated structure of the invasions (see table of treatments).

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