Senecio species are possibly the largest genus of flowering plants with roughly 1500 species, of which approximately 50 are native to Australia (Richardson et al 2007). A well known specie of Senecio in South Gippsland is Ragwort (Senecio jacobaea). Senecios are distinguished by having yellow flowers and alternately rranged leaves that often have stem-clasping ear-shaped lobes at their bases. Known to colonise disturbed areas and germinate quickly following bush-fires, Senecios are pioneering plants. In the scheme of a plant community, Senecios are understory plants with some species becoming invasive under ideal conditions.
With so many types of Senecio, correct identification can be difficult. Provided you have a sample of parts of the plant; leaves, flowers etc. below can be used as a guide to at least identify the 'bad' from the 'good'.
The Bad guys
Number of introduced species of Senecio in Victoria? There are roughly 5 exotic/introduced species of Senecio in Victoria.
What are some of the ones that are found/could be found in South Gippsland?
Ragwort (Senecio jacobaea) is a major pasture weed in South Gippsland. Cattle selectively avoid grazing it so it proliferates. Poisonous to grazing mammals, both fresh and when dried in hay or chaff, ragwort causes liver damage, leading to photosensitisation, jaundice, wasting and sometimes death.
Fireweed (Senecio madagascariensis). There are *no recorded infestations of Fireweed in the South Gippsland region, (*at the time of publication) however the growing conditions are suitable for a potential outbreak. Fireweed, like ragwort, is toxic to stock and has the potential to out compete desirable pasture grasses. This plant is a Victorian Weed Alert Weed see Department of Primary Industries Weed Alert Fact Sheet; Fireweed (Senecio madagascariensis)
African daisy (Senecio pterophorus). Found in the Port Phillip region, African daisy as with ragwort and fireweed can cause heavy losses in agricultural productivity (being toxic to stock, avoided by cattle and costly to control). African daisy grows in a variety of situations from well-drained hillsides to semi-waterlogged gullies making it a threat to near by West Gippsland. For identification and control see the Landcare Note; African daisy (Senecio pterophorus)
Number of Senecio species native to Victoria? 50, (too many to mention!) 16 of these species can be found in the Melbourne area alone (Gray et al 2006).
What are some of the common natives found/could be found in South Gippsland?
Firewheel groundsel (Senecio linearifolius) can be found in wet and damp forests in higher hills and gullies. The plant has sharply-toothed, long leaves that are dark green in colour growing to 150mm long (the leaves of ragwort are 35cm long). Flowerheads are small with 5 petals (ragwort has 12-15 petals).
Rough Fireweed (Senecio hispidulus var. hispidulus) can be found in grasslands, dry and valley forests, coastal banksia woodland and tea tree heath. The plant has toothed to –lobed, long to egg shaped leaves growing to 60mm. Image of Rough Fireweed
Cotton fireweed (Senecio quadridentatus) is the most common and widespread Senecio species, found in riparian scrub, dry and valley forests and tea-tree heath. The plant has narrow, pointed leaves to 100mm long, becoming smaller up the stem.
If the above doesn't get you to a clear point of identification, (this is likely-considering there are so many species!) then there's some great reference material to help you discover exactly which Senecio you're dealing with. See below for details.
Richardson F.J., Richardson R.G. and Shepherd R.C.H. (2007). Weeds of the South-East an Identification Guide for Australia. R.G and F.J, Victoria
