Lichen

They're beautiful. Reminds me of underwater life forms in a coral reef.

I know very little of Lichens. Is now a particularly good season to see them or something?

Perhaps you'll know. 

I was talking to a lady who does local woolen things at the market, and she mentioned her experiments of dying wool with various types of lichen, some of the reactions created or catalysed by urine (a common enough thing in history chemistry, apparently), but she couldn't be specific. 

Any idea what species might be involved in her endeavours? 

Common Haggis.

Specifically Communus Haggii.

First discovered when a highland sorcerer fell in a pool of haggis urine (they all urinate in the same spot, having compacted the ground and lined it with lichen). When he was dragged out his previously plain skirt was dyed in a perfect tartan.

Used to to be a useful commodity did urine, along with other animal excrements. Thinking dog shit for leather tanning, Guano, sheep shit for paper etc etc. Not sure what our piss was used for but I've a memory that saltpetre can be derived from it or something, and also used for leather.