Interim profile, incomplete information
Taxonomic name: Rumex acetosella L.
Synonyms: Acetosa acetosella (Linnaeus) Miller, Acetosa hastata Moench, Acetosella acetosella (L.) Small, Acetosella tenuifolia (Wallr.) A. Löve, Acetosella vulgaris (Koch) Fourr., Acetosella vulgaris Fourreau, Rumex acetosella ssp. angiocarpus (Murb.) Murb., Rumex acetosella var. pyrenaeus (Pourret) Timbal-Lagrave, Rumex acetosella var. tenuifolius Wallr., Rumex acetosella var. vulgaris W. D. J. Koch, Rumex angiocarpus Murb., Rumex tenuifolius (Wallr.) A. Löv
Common names: acedera (Spanish), acedera menor (Spanish), acederilla (Spanish), common sheep sorrel (English), dock, field sorrel (English), hierba de cristo (Spanish), hierba roja (Spanish), himesuiba (Japanese), kuzu kulagi (Turkish), lengua de vaca (Spanish), oseille (French), oseille de brebis (French), oseille sauvage (French), pactilla (Spanish), patience petite-oseille (French), petite oseille (French), red sorrel (English), romacilla (Spanish), romacilla aceitosa (Spanish), sangre de toro (Spanish), sheep sorrel (English), small sorrel (English), sorrel (English), sûrette (French), vinagrerita (Spanish), vinagrillo (Spanish), vinette sauvage (French)
Organism type: herb
Rumex acetosella is an herbaceous perennial plant which occurs in disturbed areas, such as roadsides and pastures, but also in degraded forests. A fairly common weed, it invades natural habitats more rarely as is the case in a Réunion. Rumex acetosella contains oxalic acid which can be toxic to livestock in large quantities.
Rumex acetosella is a dioecous spreading perennial herb with creeping rhizomes (Alaska Natural Heritage Program, 2006). Its stems are numerous, erect and branchy, growing 10-50cm in height (Archer & Martin, 1979). Lower leaves with petioles, lanceolate, 1-5cm in length, 1.5-2mm in width with a lanceolate or ovoid-lanceolate top part and two smaller blades. Upper leaves are prostrate, lanceolate or lanceolate-linear (Agroatlas, 2009). A membranous sheath surrounds the stem at each node
Flowers are arranged in branched loose, leafless, terminal panicles (infloresences) 3-40cm long.
Male and female flowers are borne of separate plants. Male flowers are orange-yellow; female flowers are red-orange. Female flowers have a single basal ovule; male flowers have six anthers (Pickering et al. 2003). Flowers consist of three scale-like sepals and three petals (Alaska Natural Heritage Program, 2006). Sepals of male flowers are reddish yellow, red or purplish or rarely pale green; sepals of female flowers are pure red to dark red or purplish (Agroatlas, 2009).
Fruits (achenes/nuts), often called are small (0.9-1.5 x 0.6-1mm), pale yellow-brown to slightly reddish brown, smooth, shiny (Agroatlas, 2009) and enclosed in three persistent flower scales (Alaska Natural Heritage Program, 2006).
agricultural areas, natural forests, planted forests, ruderal/disturbed
In its native range Rumex acetosella provides food for larvae of butterfly species that may be in decline, including the meadow brown butterfly (Maniola jurtina) and the scarce copper (Lycaena virgaureae) (Schneider et al., 2003).
While sheep sorrel contains oxalic acid which is poisonous to some livestock and wildlife species (Cal-IPC in Alaska Natural Heritage Program, 2006), it is grazed by mule deer. The seeds are rich food source for birds (Wilson et al. ,1999 in Alaska Natural Heritage Program, 2006).
It has also been used for revegetation in mining regions. (Alaska Natural Heritage Program, 2006) and is
eaten as a food in Turkey. A recent study demonstrated that it has antioxidant properties (Alpinar et al., 2009).
Rumex acetosella is extremely variable and taxonomically complicated polyploidy complex which includes diploids, tetraploids, hexaploids and octoploids (eFloras, Undated).
Native range: Eurasia, Chile.
Known introduced range: Australia, New Zealand, Canada, United States, Hawai'i, Alaska, French Southern Territories.
Introduction pathways to new locations
Agriculture: Seeds can be distributed with nursery stock or in contaminated seeds and hay (Gooch, 1963 in Alaska Natural Heritage Program, 2006).
Road vehicles (long distance): Seeds can be transported on vehicle tyres (Gooch, 1963 in Alaska Natural Heritage Program, 2006).
Translocation of machinery/equipment: Sheep sorrel can be transported on agricultural equipment (Gooch, 1963 in Alaska Natural Heritage Program, 2006).
Local dispersal methods
Consumption/excretion: Seeds remain viable after passing through the digestive systems of animals and birds (Evershed & Warburton, 1918 in Alaska Natural Heritage Program, 2006).
On animals: Insects (ants) are known to disperse seed (Houssard & Escarre, 1991).
Water currents: Seeds can be dispersed by water (Houssard & Escarre, 1991).
Wind dispersed: Rumex acetosella seeds are usually wind dispersed (Houssard & Escarre, 1991).
Manual: Hand pulling of plants can be effective when the infestation is small and does not yet have extensive roots and rhizome systems. Caution must be used to prevent the spread of root and rhizome fragments which can resprout. Repeated cultivation can also control sheep sorrel as continued removal of top-growth will eventually starve the roots. Manual means, are however, highly labour intensive (USDA Forest Service, 2006; GOERT, 2009).
Chemical: In general control of Rumex acetosella can be achieved with readily available general herbicides such as dicamba or triclopyr. Follow label and country requirements (USDA Forest Service, 2006). Herbicides are most effective when applied to young and actively growing plants. As R. acetosella prefers acidic soils, control can be increased when combined with liming to increase soil pH (GOERT, 2009).
Other: Rumex acetosella infestations may actually increase after grazing or burning, as it survives via rhizomes in the soil or through seeds buried in the soil. These techniques are not recommended (GOERT, 2009).
Rumex acetosella reproduces both by seed and vegetatively (Putwain et al. 1968). Clonal reproduction occurs through producton of horizontally creeping roots. Short vertical rhizomes initiate from creeping roots to the ground surface and produce clumps with one or several ramets at their tips (Fujitaka & Sakai, 2007).
Plants are dioecous, meaning female and male flowers are borne on separate plants. Flowers are wind pollinated (Houssard & Escarre, 1991). Plants can produce up to 10,000 seeds (1mm in length). Optimum temperature for seed germination is 20-22°C. Seeds cannot germinate if buried more than 8-10cm below the surface. They retain germination capacity in the soil for as long as five (Agroatlas, 2009) or seven years (Steinbauer & Grigsby 1958 in Putwain et al., 1968), although up to 80 years has been reported (GOERT, 2009).
Reproduction via seedling establishment is common in recently disturbed regions, while in dense cover vegetative propagation is more common (Putwain et al., 1968).
Rumex acetosella is a short-lived perennial herb. It grows year-round and flowers from Mayto September (in the Northern hemisphere) (GOERT, 2009). It possesses both flowering and leafy ramets. Flowering ramets consist of several leaves and a stem containing dozens or hundreds of florets; leafy ramets consist of several leaves without a flowering stem. Flowering ramets appear from early to mid summer, with flowering lasting several days. Male flowering ramets senesce after flowering, but female flowering ramets last until fruit ripens (Fujitaka & Sakai, 2007).
Male and female plants exhibit sexual dimorphism in terms of growth patterns and resource allocation. For example, males allocate more resources to below-ground organs (Fujitaka & Sakai, 2007) and appear to be more drought tolerant Zimmerman & Lechowicz, 1982). These mechanisms may have evolved to enhance reproductive success (Fujitaka & Sakai, 2007).
Compiled by: Interim profile: Comité français de l'UICN (IUCN French Committee) & IUCN SSC Invasive Species Specialist Group (ISSG)
Updates with support from the Overseas Territories Environmental Programme (OTEP) project XOT603, a joint project with the Cayman Islands Government - Department of Environment
Last Modified: Monday, 4 October 2010