Inconclusive sighting

Yes including (scientific name), Fireweed (Senecio madagascariensis) would ensure the message is unambiguous. Photos were pretty unmistakable though.

Chris the common name of Senecio madagascariensis is "Fireweed" according to the ACT Census of vascular plants, PlantNet (https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Senecio~madagascariensis) Canberra Nature Map (Senecio madagascariensis) Atalas of Living Austalia https://bie.ala.org.au/species/https://id.biodiversity.org.au/node/apni/2903107 and many other sources, in fact all sources that I checked and trust. Sometimes Madagascar ragwort or groundsel are used, however "Fireweed" is the most common used and agreed Common Name; so if we have to use common names, I'd suggest to stick with those agreed common names.

That's good to clarify that it is Senecio madagascariensis. My main point was that having the scientific name, as well as common name, on the poster makes is far easier to go straight to this species on CNM rather than having to go through the 12 species with Fireweed in their name.

Yeah, so this poster does refer to Senecio madagascariensis (Madagascan fireweed, Fireweed etc.), which is (as the name suggests) native to Africa and a weed of national signficance over here. However it is also worth noting that the name "fireweed", while it is often used to refers specifically to Senecio madagascariensis, may also be used to refer to the other senecio species or the genus more generally. In the ACT we have over 20 native species of Senecio, which are protected within our nature reserves. For the most part they are easily distinguished from Senecio madagascariensis, with perhaps the exception of Senecio pinnatifolius var. alpinus (but that is a plant of the high country as the name suggests).

Generally, I would say here that using the name "fireweed" is ok here. It is a widely name for the species in question, however I do feel that including a quick detail about its similarity to native species would be great. I have seen many examples of natives senecios being removed by folk with good intentions, when they are refered to as fireweeds.

Btw, Waltraud. There is not really any such thing as an offical common name, rather it's just what people choose to refer to a species as. Personally I've always thought of senecio madagascariensis as madagascan fireweed, and this is no less valid that using the common name "fireweed". Many species will have multiple common names, or no "offical" common name, hence it is really up to the individual observor to decide which name to use if any.

Also I think I will flag this sighting as inconclusive, there isn't any evidence of an organism. But it is worthwhile keeping the disucssion on platform.

I know the common name is a fickle thing and may be used according to preference by the user; "Fireweed" is the most used Common Name for the species as far as I can see. Now, I must admit I was one of those uneducated with good intentions. When I came across weedy looking Senecio, I pulled them out along Casuarina trail. Turned out to be S. bathurstianus. It was a very important lesson for me when a friend pointed out my mistake. I know the Senecio genus from Germany (hated them when i had to id) and wrongly assumed it was one of those and exotic in Australia. BTW there are/were 100s on mt Majura - so no way to eradicate....

Madagascan fireweed arrived in Australia last century but as pointed out there are many native fireweeds; usually they have an adjectival prefix. By the way, the list of Senecio does not get as far as S. quadridentatus (cotton fireweed) as the dropdown list is limited to 20 entries; this is a fault with trying to access Collections. Just to ensure this discussion of fireweeds doesn't get lost, I have added it to the Collection 'Discussions' (rather than 'Talking Points' which got knocked off the list.).