All your photos here listed under Erigeron compositus are actually some Leuchanthemum species, probably L. vulgare. --Pitke (talk) 21:39, 28 April 2013 (UTC)
Hi Pitke, Thanks for your message! First of all, I would like to thank you for all the nice categorization work I have seen lately with detailed close-up of ... categories and various other improvements. Very nice! Concerning the erigeron compositus - are you really sure it is misidentified? If so, why?
I recall that back then I felt very certain that it was indeed erigeron compositus. It is almost six years ago, so I do not exactly remember why, but one of the factors was that distribution maps in the Grenlandic flora books I had did not really indicate that there were really no other options then erigeron compositus for this flowing plant located in Ilulissat if it were to match the distribution maps I had. But, these did not completely cover invasive species near towns and settlements I should say, so you may have a point.
Since then I have also lost most of my competences in id'ing arctic plants, as I have not maintained my skills (or lacking skills :-) ) since I had the oppurtunity to stay in North-West Greenland for three months in the Summer of 2007. I have three different flora books dealing with the flora of Greenland, which I have used as a reference, but they are now archived in my attick (this case could trigger me into retrieving them).
I know that the photos do not look very typical of other photos available of this plant, but I think it may have something to do with the location. The plants were situated in a moist area where water from households where flowing on the ground. So I guess it was a very nutricious environment, so the plants may have been more nourished than typical when found wild?
You mention it could be some Leuchanthenum species, probably Leuchantenum vulgare. If I take a look at en:List of flora of Greenland#Asteraceae, Leuchantenum vulgare is indeed mentioned as an introduced species in Greenland - and the only species of the Leuchantenum Genus in Greenland. If I do a Google search for "leuchantenum vulgare Greenland" I find This perennial species is perhaps persisting vegetatively but not seed-reproducing in southwestern Greenland (Pedersen 1972). Now, I do not have this reference and it is also old, so things may have changed, but I do not consider Ilulissat as part of South-West Greenland. Actually, the climate in South-West Greenland is (as I perceive it) significantly milder than in Ilulissat. But maybe this has changed significantly since 1972 or new evidence has been collected? Anyway curious to hear your comments.
Back in 2008 I also discussed the erigeron compositus photos without another photographer of this plant, which adds some details I had forgotten now.
I would be interesting to hearing your comments to this. --Slaunger (talk) 22:03, 29 April 2013 (UTC)