ebgood's picture


Observed: 16th February 2011 By: ebgoodebgood’s reputation in Fungi and Lichens

Lichen. Crustose observed on sandstone wall.Yellow, powdery. Very sparse on wall.


Caution: Do NOT use iSpot to identify fungi to eat!

Some fungi are very poisonous so a mistaken ID could have serious consequences.

Species interactions

No interactions present.


gardener's picture

Spot tests

Your ID could well right but you need to spot check it with K to be certain that its not a Caloplaca. Candelariella sp. are K-, Caloplaca sp. are K+ red

BLS Lichen reagents:

ebgood's picture

Thank you Jenny. As this is

Thank you Jenny. As this is only the 3rd lichen I have looked at I don't even know what spot checks are. I assume K to be potassium or a solution of (did chemistry 50 yrs ago!) Will try to find out more about testing thank you once again.

gardener's picture

Spot tests

There are chemical compounds present in some lichens which will produce different coloured reactions to a (tiny) drop of the reagent.
The link in the post above takes you to a page on the British Lichen Society that gives more information.

K (Caustic soda) and C (cheapest, thinnest household bleach with no additives e.g Tesco's) can be obtained easily and you can get small dropper bottles from most chemists.

I've given spot test results for all the species included on the Irish Lichens website: www.irishlichens.ie
Clicking on the thumbnail images opens an information page for that lichen. (The species shown are also found in suitable habitats in the UK)

The iSpot Fungi and Lichen forum has a couple of threads with links to Lichen identification keys and resources:

ebgood's picture

Thank you very much. Very

Thank you very much. Very much a novice with lichen. I will certainly look up your sites.