African Daisy (Senecio pterophorus) is an erect, tufted, perennial shrub 1-1.5 m high, with several stems per plant. The stems are greyish-green and ribbed length-wise. The lower parts of the stems develop distinctive wings which extend down from the bases of the leaves. The leaves are leathery and lance-shaped, 5-14 cm long and 3-25 mm wide. The lower leaves have 2-8 forward-directed teeth and the upper leaves are generally without teeth. The upper surface of the leaf is glossy-green, and the lower leaf is white or grey with a cobweb like appearance. The flower heads are generally 10-20 cm across, with 40-200 or more individual flowers. The ribbed seeds are 1.5-1.8 mm long, brown or reddish-brown, with minute hairs in rows which are pressed to the surface of the seed, and topped with a ring of slender, deciduous, white hairs (Parsons & Cuthbertson 1992; Walsh & Entwisle 1999; Navie 2004).
For further information and assistance with identification of African Daisy contact the herbarium in your state or territory.
African Daisy is naturalised in south-eastern South Australia, from the Eyre Peninsula, south-west to the Victoria border. In Victoria it occurs in scattered populations, from the South Australian border, east to Garfield in south-central part of the State. In New South Wales it occurs in central-eastern New South Wales from Newcastle, southwest to the Blue Mountains (AVH 2007; National Herbarium of Victoria 2007). There is a single collection from the Australian National Botanic Gardens (ACT) in 1972 but it is not clear whether this represents a naturalisation or a casual introduction that did not persist.(Australian National Herbarium 2007; Lepschi pers. comm.. 2007)
- African Daisy (Senecio pterophorus) is an aggressive pioneer species that is native to South Africa, and readily invades disturbed sites.
- In natural ecosystems the African Daisy is strongly competitive, and can form dense thickets that exclude native species.
- In agricultural areas, it can greatly reduce productivity rates.
- Larger populations can be controlled by cultivation and grazing, slashing, and herbicides.
How it spreads:
The seed capsules of African Daisy are adapted for spread by wind, but because the outer shell is shed easily most of the seeds fall close to the parent plant (Parsons & Cuthbertson 1992). Most dispersal is by wind, water, animals and vehicles. However, some spread may also occur in contaminated soil and agricultural produce (Navie 2004).
Where it grows:
In South Africa, African Daisy grows in areas of moderate to high rainfall (500-1500 mm) (Parsons & Cuthbertson 1992), and in Australia, it tolerates a wide range of soil types (National Herbarium of Victoria 2007; State Herbarium of South Australia 2007). In Australia it often invades roadsides and railway lines, cleared paddocks, denuded grazing land, newly sown pastures, and native vegetation (Parsons & Cuthbertson 1992; National Herbarium of Victoria 2007). It grows in a variety of situations from well-drained hillsides to semi-waterlogged areas (Faithfull 2007), and in Spain, it forms dense infestations in riverbeds (Thorp & Wilson 1998 – ). Native vegetation invaded by the African Daisy include lowland grassland, grassy-woodland, heathy-woodland and dry sclerophyll forest, usually following disturbance, particularly fire (Carr et al. 1992; National Herbarium of Victoria 2007; Stajsic 2007, pers. comm.).
Flower colour: Yellow
African Daisy is an aggressive, pioneer species, which invades sites that have undergone some sort of disturbance such as clearing, soil degradation or fire (Parsons & Cuthbertson 1992; National Herbarium of Victoria 2007). It can outcompete other plants and become dominant. In agricultural areas heavy losses in productivity can result (Parsons & Cuthbertson 1992). In natural areas the plant is a strong competitor, forming dense thickets that exclude native species (Faithfull 2007). African Daisy contains the toxic alkaloids senecionine and seneciphylline but is apparently rarely eaten by grazing livestock (Parsons & Cuthbertson 1992). No stock deaths have been reported in Australia. However during feeding tests in South Africa sheep suffered severe jaundice and died (Parsons & Cuthbertson 1992).
African Daisy is native to South Africa (Parsons & Cuthbertson 1992; Thompson 2006).
African Daisy is believed to have been introduced to South Australia in ship ballast at Port Lincoln in about 1930 (Parsons & Cuthbertson 1992). From there it spread to the Adelaide Hills and occupied much of the southern Eyre Peninsula and south-east South Australia in areas with over 500 mm annual rainfall (Parsons & Cuthbertson 1992).
The first record of the species in Victoria is from Coode Island in 1908, but it did not become invasive in Victoria until about 1972 and current infestations are believed to be a result of spread from South Australia (Walsh & Entwisle 1999; National Herbarium of Victoria 2007).