So, I ran into this observation. I thought, sure, it looks like Usnea, but it’s so in the middle of a residential area, right at the side of Helsinki, maybe 5 km from Helsinki-Vantaa International Airport, and even less from a busy highway (E18) that it just can’t be. I told as much, and said I think it might be Evernia of some weird kind (but also that it still looks more like Usnea than Evernia). I wasn’t sure one way or the other, so I just ID:ed it to Parmelioideae and left it at that. I’ve been taught, that Usnea are among the first to go if the air starts getting polluted.
Now there’s a biology student, focusing on lichens ID:ing it also a Usnea. I am very confused. I pinged her in a comment asking her to tell me how this could be, hopefully she’ll answer, but I’m just baffled. I’m also excited, since I might learn something new. Just had to get this off my mind here. If someone here can tell me something about this, I’d be happy for that also.
I havent heard the no cities thing. I have seen them in several cities. Growing off all sorts of things. Looking at usnea obs in some of the cities I have been in I see several usneas, which are ones I would expect.
" They vary in colour from pale green to yellow-green, grey-green, reddish, or variegated, and range in size from a few millimetres in polluted areas to over three metres long in species like Usnea longissima ."
I see wiki suggests they don’t grow as well in cities. But I haventt dug deep into that. I guess the ones I think of in cities, are a lot smaller than what I see in “goblin forest”
Apparently, Usnea are sensitive to SOx pollution, and that has dropped greatly (over 90%) in Finland since 1990’s (early 90’s would be about when I was taught this, so that’d explain). NOx is the second one, but not as bad. High smokestacks have also made the pollution much more diffuse.
To quote her on current limitations: “As a result the occasional Usnea thallus can now be found far into cities in many places again. The limiting factors will often be availability of suitable habitat, dispersal, and agricultural ammonia pollution especially in areas with intensive animal husbandry.”
All good, working in a national park visitor centre, my fave questions are ones along the lines of “I noticed that X, what/why/how is that”. Its always interesting to figure those things out.
Yeah. One of the coolest things was when I was working at a city bureau in the info. Normally, it was just routine, but sometimes people had really interesting questions. There was a wall relief next to the info, but it had no labels or markings. One time, a couple asked me about it, and I had to answer that I have no clue, but if they give me their email, I can try to find out and send them the info.
After many twists and turns, a lot of websearching, emailing and calls, I tracked it to be from the city’s own collections, the first appearance in the background of a photo from the late 50’s in a different place altogether. So I called the head curator of the city’s art collection. She was immediately interested and asked me to send a phot. The next day she sen me an email ecstatically telling that it’s one of the works that had become lost during the change of head curators and the information system in the early 2000’s, and gave me the background for the work, which I then passed on to the couple to their delight.
But what has seemingly become my motto is, what my father often said: “If you don’t know, ask. If no one answeres, find out.”