I’ve recently been observing a lot of lichen in Mass. and was looking at two different locations in the state (one town near Boston and one in the Cape). I noticed that there were no fruticose lichen closer to the town near Boston in the area I was taking data from, and there was a surprising abundance of fruticose lichen in the Cape. I was under the impression that fruticose lichen were much rarer and I didn’t expect to find so much of it, does this mean the Cape area is really good in terms of air quality or are fruticose lichen much more common than I think? Also, does the lack of fruticose in the town closer to Boston really impact the air quality there even though I found a lot of crustose and foliose lichen?
another student asking questions for a school project…
do you actually have reason to believe that air quality near Wellesley is worse than air quality near Cape Cod? (if so, by what measures? so says what source?)
how common do you think they are?
are you suggesting that the presence or absence of these lichen has a noticeable impact on air quality?
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Just to say I read before deer feeding on lichen. It is a lifeform that supports other creature. From a gardener’s point of view, lichen do not look great on tree bark. It is impossible to control it though.
The presence of diverse lichens is a sign of healthy air quality. It does not cause it.
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Lichen does no harm at all on tree bark. It is good biodiversity and should never be removed.
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wait until the sun has gone down, and then shine a UV light on them.
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From another gardener’s perspective, lichens are gorgeous. I have water oaks in my yard which is a common native species here that has an annoying habit of dropping lower limbs*. I always save them and put them in and around my flower beds because they are covered in a vast array of lichens, orange crowded parchment fungus, various jelly fungi, and sometimes a pretty purple crusting fungus.
*I currently have a water oak limb stuck up in a juniper tree where it’s bending down a bunch of branches making a big ugly hole. It’s too heavy to push up to get it over the branches it’s stuck on because it’s not rotted. The oak limb still had a small number of green leaves on it before the tree went “I’m done with this now.”
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Lichen growth form is mostly a function of moisture type and availability, it’s not quite as simple as fruticose=good air, crustose=pollution tolerant. Lichens are very good indicators of air quality as well as things like nitrogen levels in all habitats. In many deserts and open shrublands, soil lichens are indicative of high-quality habitat that is not heavily disturbed by humans or doimestic grazers. Mediterranean habitats like the Cape have a lot of lichen diversity, especially on the coasts where fog is abundant. I would expect the high levels of fruticose lichens in the Cape is more a function of climate than air pollution, especially if you looked near large cities in the Cape as well.
Edit: I just realized you mean Cape Cod and not the Cape of Africa, so discount what I said about mediterranean climate, but I am sure the ocean does have some effect.
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Nonsense. Lichens look marvelous on tree bark. They add all sorts of interesting patterns and colors, many kinds are beneficial as well.
A wide range of lichens are nitrogen fixers, benefitting the plants in their immediate area and enriching the soil. This is true both of soil crust lichens and lichens on trees and rocks.
Thread-like and foliose lichens also benefit trees enormously in foggy areas by providing condensation surfaces, adding to the available water the plants need.
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Lichens are also an important source of food, habitat, nest material, and camouflage for a variety of creatures. Just on a single red maple in the yard of my childhood home, I would find grizzled mantids blending in with the lichens perfectly, lacewing larvae and bagworm larvae using lichens as part of their camouflage, and lichenicolous fungi growing on the lichens. Without lichens, none of those organisms would have been there. I wonder what lichen-dependent species are absent from the places you visited that once occurred there (if lichen diversity was indeed higher there in the past). I’d also like to add that fruticose lichens could include Cladonias, which are some of the most common lichens anywhere.
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In every place there’re specific species of lichens that survive only in better air conditions, like Lobaria, their presence means it’s a very fine place, lots of random lichens is a sign it’s probably still good, just a dozen of common urban species would mean you’re looking at a tree in the middle of the city. And as others said, lichens are mark species you can use to check the quality of air, they themselves don’t affect it.
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My Cape - but agree with you about moist sea air probably makes a difference. Come to think of it, not much lichen on my garden trees, but I see it on our more coastal walks.
It reads suspiciously like homework to me
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By what mechanism might lichen, or lack of, impact air quality?
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If this is a homework question, then my question is why don’t teachers teach how to effectively use search engines?
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47 observations, 48 of which are of lichens, but all but they are all lumped on two days only in two locations. The distribution and timing looks a lot like the sort of assignments given out in field labs in undergrad courses.
It’s not definitive, but it does lend credence to the idea that it’s class related.
And this post is similar, and for the same area:
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Well, at least they went out and made observations I guess (hope)
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That is directly adjacent to the first single-day batch of lichen observations, as well as the 1 earlier non-lichen observation.
When I was a TA for ecology based classes in grad school in New England it was common to take a class lab or field session out to a nearby park, ideally one walking distance from campus. After that individual students were encouraged to find their own locations for individual projects.
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