AlanS's picture

crustose, foliose, fruticose - are we being exploited?

There suddenly seems to be a glut of observations featuring lichens, but with no attempt at identification to species and concern only whether the lichen is crustose, foliose or fruticose (and often getting these wrong and misunderstanding the foliose/fruticose distinction - many foliose species have aerial branches!).

I have been providing identifications where possible, though the photographs are often of low standard, but I am starting to wonder about this whole phenomenon.

I note that all these posts are coming from Open University students. Has someone set them an exercise to go out and take low resolution, out of focus photographs, post them as observations with IDs only to "crustose, foliose, fruticose" and get mugs like me to tell them if they are right? If so, I have plenty of my own coursework and exam papers to mark.

Anyone trying to get to know the lichens of their own area will usually meet a lot of very poorly developed urban specimens of genera that are difficult even with good material. I for one am happy to help, when/if I can (displacement activity to put off my own marking), but I have decided to ignore posts that seem only interested in the flawed and arbitrary classification of convenience, applied by us humans, to the large and more or less continuous diversity of lichen structure.

And what about leprose, squamulose, etc.?




AlanS's picture

And is this the perfect example?


Posted as "foliose lichen"

I add a revision giving the name of the species.

Original poster attempts to change the ID back to foliose again by adding a redundant revision!

or how about:

I provide the species ID, original poster adds a new revision to keep foliose in the title

or how about:

Here the poster has accepted the ID, but posted it again herself as a redundant new revision, presumably to collect agreements?

or how about ....
well ok, I have made my point.

I am happy to help those who genuinely want to know what they have seen, and even if it is something common and easy, it may well be that the poster is primarily interested in another group. No one should be expected to own a complete set of field guides.

There is nothing wrong with somebody making an attempt at an ID and saying they know or think an unknown is foliose but they are stuck in taking it further. But when it comes to people using crustose, foliose and fruticose as pseudo-identifications, I think this is an abuse of iSpot and those of us who try to help.


DaveDenison's picture

Glut of lichen hunters?

I'd say your guess was right, Alan.

I've just joined up for my first OU course starting 14 May, S159 - Neighbourhood Nature. The first activity is a "lichen hunt". The three types defined in the Activity Notes are crustose, foliose & fruticose, and we are asked to go out and spot these around our houses. We are also asked to register on, and investigate iSpot(...though not necessarily log our specimens). So your detective work seems spot on!

Sorry if this is causing you some frustration, but as a new student, I'm just trying to get a grip of the materials I've been provided, in what - to me - is an unfamiliar environment.

Perhaps you can check up with the course organisers?

Dave D.

Gentiana's picture

Lichen ID

I am not a specialist in lichens - I appreciate them aesthetically and am not too bad at the big floppy ones in the atlantic oakwoods, but a while back decided to concentrate on other groups. I've been extremely fortunate in having patient, helpful people to support me - especially in the early stages when really the most important thing is to learn how to look at something, what the important features are and how to describe them. There are some really useful web resources - one of my favourites for lichens is, put together by Mike Sutcliffe. It has a great introduction to the structure and growth forms of lichens and to the sexual and vegetative reproductive structures. And it's really well illustrated with fantastic photos.

Hope that helps

Myra W's picture

are you being exploited?

Hi Alan,
Like Dave D, I have just started this OU course and the first instruction is to go out and see if we can find lichen and then write it up. As only three examples are given (crustose, foliose and fruticose), I'm afraid as a complete rookie in this field I couldn't contribute anything but the basic info. Even iSpot is new to me (and probably most of us)! I'm sure this must be so frustrating for you, but would it help if I told you that you have already helped and encouraged me by responding to my post. Still, maybe you should just ignore us newbies till we get the hang of it, now that you know we are just practicing and finding our way around the site. Regards, Myra

gardener's picture

Hi Alan, I came to the

Hi Alan,
I came to the conclusion a while back that this isn't the OU students fault but rather the responsibility of those who designed and run the Neighbourhood Nature OU course.

I queried this a while ago with Martin Harvey, and I hope he doesn't mind me quoting his reply below:

"The OU students on the Neighbourhood Nature course are given an exercise in recording lichens, but are only asked to specify the growth form and colour. They are not expected to get a full ID, and are not specifically asked to put lichen images on iSpot , but of course they get hooked and do end up putting lots of them on iSpot. The feedback that we’ve had shows that in many cases they are just seeking reassurance that they’ve actually allocated them to the correct growth form, and are very happy if they get a response that simply confirms something as being crustose or foliose etc. (in fact it is the choice between foliose and fruticose that seems to cause the most uncertainty). If a species, genus or group name can be given that is a bonus."

I'm glad to be able to help people with a genuine interest in learning more about lichens, but (feeling slightly cynical) wonder how much input into the lichen part of their course the OU lecturers actually provide.

AlanS's picture

Several issues

Thanks, folks, for clarifying the situation.

First of all I want to respond specifically to Myra - "Still, maybe you should just ignore us newbies till we get the hang of it, now that you know we are just practicing and finding our way around the site."

Absolutely not! I am glad I was of help, and giving help to "nubies" is one of the most important aspects of this site. There are various levels of nubiehood, and having been out with some of the real lichen experts on a British Lichen Society meeting in the last few days, I am acutely aware (as if I wasn't before!) that I have not yet passed beyond nubiehood myself. I have not forgotten various confusions of my own when I first became addicted to lichens, and if I can help other people through them, that's great.

But if someone is only interested in three arbitrary grown forms and doesn't want any further help, than that's where I feel others of us are wasting our time. I think this should be made clear in posts.

Judging by some of the incorrect claims of fruticose species, I do wonder what instruction has actually been given. Very often, foliose species, as well as being leafy, are pretty much flat on the substrate, while fruticose species usually have aerial branches, but there are common foliose species (e.g. Evernia prunastri) that are also much branched and hang out into the atmosphere. The critical feature is that foliose species have distinct upper and lower cortexes (i.e. they are different underneath) whereas fruticose species have a continuous cortex both sides if they happen to be flattened. This means that Evernia is foliose, while superficially very similar species of Ramalina are fruticose. And just as foliose species can stand away from the substrate, it can also happen that fruticose species are prostrate. (Only one example comes to mind as I write this, but I am sure there are others.)

I feel this exercise should require more detailed observation, making sure to look at undersides, and while I have to admit we use the same crustose-foliose-fruticose classification in our own first year classes, I would think that people who are going out to look at these things should be aware that not everything conforms to them and that there are other categories. The introduction in 'Dobson' is very good in this respect. And if students have to look at the lichen in some detail, this may well spark further interest.

I agree completely with Jenny's last paragraph.


ds9457's picture

Incorrect lichen id

First of all I would like to introduce myself as a 'guilty' party here. I too am just starting the OU S159 Course. I feel quite disappointed that I have obviously failed to a) be able to identify a basic lichen correctly and b) seem to have caused some 'waste of time'. However in my, and others', defence we were sent out on a very simple first activity as part of our course with what I now see was very simplistic information, including a few generic photos of 3 types of lichen.
I had no way of checking my own identifications and unfortunately was not aware of any other growth types. Hence why I thought it a useful idea to obtain assistance with id. However it appears that I may have not understood fully how ispot works or how to use its resource correctly!
The only other rescource of this type I have used in the past, was the Natural History museum website, which encourages users to upload photos for identification. They seemed quite happy to provide any necessary assistance to the keen and ignorant.
I have now removed my 'observation' as I don't regard it as a genuine ID. I for one certainly don't want to 'cheat' and obtain lists of agreements incorrectly.
Debbie Scott

ph4877's picture


I have just started the OU course S159 Neighbourhood Nature like many others. And as already mentioned the first activity on the course, has been to look close to our homes for lichen and the only information we have been given is the 3 types, crustose, foliose, and fruticose. So with this to hand thought the best place to get help and advice was on i-spot to help with identifications.

I am sorry for any problem I may have caused. I have now removed my "observation" where I changed my original ID. I thought at the time it was correct to change my original thoughts but that would appear to be the incorrect method to use on i-spot. Once again I am sorry and there is no way I would wish for anyone to think that I was cheating. Far from it, I just wish to learn.

I will in future try to take better photos for ID purposes and attempt to make correct identifications. At the time I was unable to see other lichen in my photo at the time, due to being a first time observer. However with the help of Alan I have learnt to see others.

So I would like to say on record a thank you to Alan for his help and advise and sorry to have cause any problems. And thank you to others who have helped with their thoughts.

Regards Pen

vs4369's picture

Neighbourhood Nature lichen.

As a previous Neighbourhood Nature student I would like to agree with your comments on the lichen study. Students are asked to hunt for lichen in their home area and classify it only by colour and type (crustose, foliose, fruticose). Then note and discuss what types of surface the lichens are found on and facing which directions etc. Everyone comes up with inconclusive, confusing and contradictory results which is to be expected and the conclusion is reached that to gain meaningful information from a study it must be done far more specifically and scientifically. Then the lichen part ends.

Whilst suddenly becoming very aware of and interested in lichens we students do not actually learn much more than they can be different colours, crustose, fruticose and foliose from this course. The exercise is not really about lichen at all, the subject could be anything and lichen are used because they are evident all year round to fit with the differing seasons the course falls in.

Personally I would have liked some more detail on the lichen part and the opportunity for some answers to the different questions raised in the study but the course moved swiftly on. Perhaps some people may feel inspired enough to develop a longer term interest in lichens but they are a very complex subject and this course definately does not do them justice.



Jonathan's picture

Dear Alan, Jenny and current

Dear Alan, Jenny and current S159 Students,

I think that there has been a misunderstanding that I hope I can clear up. As Martin said in his quote posted by Jenny (and thanks to her for doing that), S159 Students are not asked to post lichen observations on iSpot. The lichen activity is self-contained and does not depend on iSpot or iSpot experts. Guidance is given as to its purpose, and the exercise is not meant to be an introduction to lichens. Rather, lichens are being used as a means to an end.

We are very grateful to all the experts on iSpot for their contributions, and you must know that this feeling is shared by the rest of the growing iSpot community. One of the unique things about iSpot is that it successfully connects beginners and others with varying levels of expertise. Beginners make mistakes, but there are plenty of people to put them right on iSpot now if the mistake is elementary. If you have high expertise and there is a sudden rush of observations in your group (this can be due to seasons as well as S159!), I suggest you are more selective about which (if any) you respond to. It would be much better to do that, than to feel exploited.

Finally, iSpot is addictive. I understand that, but everything needs to be kept in proportion -- even (I hate to say it) iSpot.

University of Edinburgh and Biodiversity Observatory (OU)

gardener's picture

Clarification appreciated

Thanks for your input Jonathon, but I'd appreciate a bit more clarification as to the inter-relatedness of the OU courses and iSpot.

On the one hand:
"As Martin said in his quote posted by Jenny S159 Students are not asked to post lichen observations on iSpot. The lichen activity is self-contained and does not depend on iSpot or iSpot experts"

Yet, and not just from the post quoted, but from many other OU students:
"We are also required to register on iSpot and enter our findings."

From the OU website, course 159 Neighbourhood Nature:
"You will learn how to observe, identify and record the wildlife around you, building up a picture of a small part of your local environment. When put together with the observations of hundreds of other people, recorded on the iSpot website, a much broader picture of the wildlife of the country will be created. Changes over time will also become apparent as data accumulates."

Clarification appreciated!

Jonathan's picture

Dear Jenny,Students do the

Dear Jenny,

Students do the lichen study as an introductory exercise and this does not require the use of iSpot. Later, they are required to post 10 observations (not of lichens, though these are not disbarred) on iSpot and then to write about what they have found etc. From the point of view of other users of iSpot (eg yourself) the fact that some observations come from S159 students should be irrelevant. We certainly don't expect, or lead our students to expect, that their observations will receive special attention.

Does this clarify the situation?

I can tell you for a fact that students of other universities use iSpot, but I have no idea who they are, nor should it matter. If iSpot works, then some of these students will become the experts of tomorrow and the whole community will benefit. That's what we all want to happen.

University of Edinburgh and Biodiversity Observatory (OU)

diggleken's picture

Quite agree Alan,well said,

Quite agree Alan,well said, ID shallowness isnt right if we want science to be accurate and realistic.

Jonathan's picture

I'm a bit lost as to which

I'm a bit lost as to which comment this is in reply to, but want to point out that the observations of lichens in S159 are not used for naming purposes, but to introduce beginners to the variety that may be found in a taxon, before they get stuck in to the details of how to ID things. iSpot is a tolerant community and all the better (and unusual) for that. Let's keep it that way.

University of Edinburgh and Biodiversity Observatory (OU)

NormanK's picture

Are we being exploited

Alan S - I am disappointed by your post. I am an OU student doing the S159 neighbourhood Nature course. Our first Activity introduces us to obversation by looking for lichen, and attempting to classify it as crustose, fructose or foliose. We are also required to register on iSpot and enter our findings.
I don't know what you are expecting, but we are far from being experts, and what you see are the efforts of people new to the subject, but making an honest attempt. It is not a "phenomenon" as you put it, and if you have a problem I suggest you take it up with the OU - if you have time in between your own coursework and exam paper marking of course!

gardener's picture

Lichen identification key

I've a lot of sympathy with OU students who, for their first activity, are required to observe lichens - they're not an easy subject at the best of times!

There don't seem to be clear guide lines available on how to use iSpot either, so that makes things more difficult for people who are possibly new to the OU, digital photography and on-line forums.

For anyone interested in taking their identifications beyond the basic 'crustose-foliose-fruticose' stage the Natural History Museum has a good 'starter' key:

There is also a thread in the Fungi and Lichen Forum with links to some Lichen Identification Resources:

ph4877's picture

Useful links

Dear Jenny

Many thanks for your useful links.

Hopefully these links will help us who wish to understand the complex variety of lichens.


Martin Harvey's picture

Lichen links and iSpot guidance

Thanks for the helpful links in your comments above Jenny. There some more links in the "Fungi and lichens" group page on iSpot, available from the "Groups" link at the top of the iSpot pages or go direct to:

Jenny: you also said "There don't seem to be clear guide lines available on how to use iSpot". There is of course our Help page at:

but presumably you had something else in mind? Do let us know what sort of guidance you feel would be most useful and we'll see if it can be added.

Entomologist and biological recorder

Myra W's picture


Dear Alan
POOR YOU - I bet you are considering a new subject to study....the hornet's nest! I'm sure you didn't realise you would be stirring up such a furore!!! I can understand early posts (that would be me!) from people who weren't perhaps clearly directed by OU, but now that it's all been explained and anyone in this forum can see the depth of the discussion, I hope that's the end of it? Time to move on, isn't it? I hope you will continue to give your helpful input to the observation forums.......I might be posting a fungal "blob" (looks like a mushroom, but no stem)in a day or two, but I'm going to have a stab at identifying it myself first!
Good luck

Dioctria's picture


Yes, I too hope your valuable contributions will continue.

And while I'm about it I'd like to place on record my gratitude to all the experts and keen amateurs on iSpot who give so freely of their time and knowledge to help others understand and appreciate the natural world.

Thank you!


Jackie Williams's picture

S159 students

I do hope that following the recent 'discussions' regarding OU students posting lichen observations with oversimplified identifications won't lead to too many i-Spot users assuming that all posts by OU students are all likely to be of this type!

Personally, I read all the information supplied to me when I registered for this course in February and my understanding was that the lichens we found did not even need to be photographed, let alone posted on i-Spot. Indeed, most of those which I found were logged on the recording sheet provided and then discussed on the relevant OU student forum - this was what we were asked to do and even then, I doubt that anyone at the OU will be closely observing whether we have actually done this or not. To me, there clearly seemed to be no need to put any lichen findings on i-Spot unless we get to later activities and chose to select lichens as part of our field study for the final assessment.

I have since put one photo of a lichen on i-Spot with a tentative identification, as it was a particularly large and clear looking example that I found. In this case, AlanS was very helpful in pointing out that I had likely got the correct genus but probably not the correct species - unsurprising as a beginner but I was pleased that I wasn't so far off and I was very grateful for Alan's helpful pointers.

I hope that following the recent discussions above, there is sufficient clarification for us all to be happy to post observations on i-Spot in future with sufficient information to help other users to help us with our identifications.


debbieC's picture


I have just completed the Neighbourhood Nature course, and initially posted several of my lichen obs on ispot. I work nights, and often log on after work, to wind down a bit. One evening I read some very discouraging, and downright rude comments, not only about my ID, but ispot itself, from Alan S who was also online. Being new to the course, which is about HOW to observe, research, and ID nature, it put me off posting any more lichen. I'm not easily rattled, but the tone of the comments really threw me. I took deep breath, and went back to the post to respond, only to find he had edited it. It makes me wonder if others felt the same and stopped posting their findings.


Jonathan's picture

Debbie, I think that this was

Debbie, I think that this was all a storm in a teacup and if you read back over the earlier postings in this thread, the issue had been resolved. Things can get a bit overheated online, but it is remarkable how friendly 99% of the interactions on iSpot are, I hope you will agree. Alan is fantastically knowledegable and supportive.

University of Edinburgh and Biodiversity Observatory (OU)