S. junceum is a perennial shrub, 2-4 m tall. Slender stems erect with few branches. Stems cylindrical, rush-like, and green when young, maturing into woody branches. Mature plants have one to several trunks. Leaves are caducous, oblong-linear to lanceolate, 2-2.5 cm long, smooth-margined. Leaves are ephemeral, remaining on the plant for four months or less. Inflorescence is an open terminal raceme with several flowers. Flowers pedicellate, pedicels with a small caducous bract at base and two bracteoles at apex;corolla yellow, 20-25 mm long, anthers with a tuft of hairs at base. Fruit is a linear, dehiscent legume, 5-10 mm long and 5 mm wide, with 10 to 18 black seeds (Wagner et al., 1999;Zouhar, 2005).
Related crop
- Euphorbia
- Rumex
Related invasive species
- Euphorbia
- Sonchus
- Rumex
- Artemisia
Related Farm Practice
- Invasive species
- Hosts
S. junceum negatively impacts populations of Corema album and Picconia azorica, two species listed as endangered in the Azores, as well as populations of the endemic species Erica scoparia subsp. azorica. Across the Canary Islands it affects populations of Aeonium ciliatum, an endemic species listed as vulnerable, as well as the following endemic species: Genista canariensis, Hypericum grandifolium, H. canariense, Andryala pinnatifida, Rumex lunaria, Artemisia canariensis, Argyranthemum frutescens, Euphorbia lamarckii, Sonchus acaulis, S. congestus, Micromeria varia and Adenocarpus foliolosus (Silva et al., 2008). Other species native to the Azores and the Canary Islands are also affected by the invasive nature of S. junceum (Silva et al., 2008).