In a small biography on the life and work of Marion Campbell, which I bought in Tarbert, Isle of Harris, crotal * (in this case Parmelia Saxatilis), a coarse rock lichen, is mentioned as one of the dyes for wool. After I asked our host about it he went out and brought a handful. I was glad to see it – I find it difficult to look for lichen just with a book. I gathered some more from rocks and dyed with it at home. I forgot to take a photo when it was dry but here it is, soaked with water from the dyebath.
and here the colour it produced: merino wool on the left, silk chiffon bottom right, unbleached cotton muslin top right. None of them were mordanted, since lichens are substantive dyes and mordant is not necessary to keep the rich rusty red brown colour permanent.
* the name crotal was a common name for lichens in Scotland
Colour from lichens can be extracted by boiling, by fermentation or by both methods, in which case each method gives different colour. From Parmelia Saxatilis it is extracted by boiling only.
I dried the lichen and then crumbled it between my fingers. If used fresh, again, it’s recommended to bruise the plant, breaking across the whole center. The dye acids may lie under the skin of the plant or right in the center and are released much easier and better if the lichen is broken. This should be done when dyeing with any lichen. The crumbled plant went into a pot, water added and brought slowly to simmer. After about an hour I added some vinegar, books recommend about 2 tbs per gallon- and then fibres.
In the past alternate layers of wool and crotal would be packed in the vessel. Books say the plant doesn’t attach much to the fibre and can be easily shaken off. Well, I am sure this is true if eg. Scottish Blackface, common for making Harris Tweed, is dyed as it is coarse, almost double in micron than my merino 18 mic. The lichen in my pot ‘bonded’ with it and it will require some serious carding before I break this friendship. Next time I am going to tie the lichen in a muslin/chiffon bag to keep it separate from the wool, but I expect the hue will be weaker. I have noticed where bigger pieces of lichen were in contact with the wool the colour is much darker.
I left the fibres in the dyebath for about 3 hours, altogether cca 55 g per 80 g of dried lichen. I exhausted the bath with a lenght of silk ponge which dyed medium tan colour, similar to tea.
Parmelia Saxatilis is extremely common here and I have already gathered more to try the ‘separate’ method.
Literature:
- Gisela Vogler, A Harris Way of Life
- Robertson, Dyes from Plants
- Eileen M. Bolton, Lichens for Vegetable Dyeing
- Wickens, Natural Dyes for Spinners and weavers
Red 2 White 
Very very interesting, and the result on wool is striking !
I think I know a place (unfortunately not that close from where I am) where a similar lichen grows abundantly. You’re making me want to investigate & remember to pick some the next time I’ll visit that place.
Great post! Most helpful. Lucky you, on Harris!
Thank you.
Wendy
Lovely results! I’ve never tried it on silk myself. I have used Crottle a lot over the years and find that if the lichen is crumbled it is much harder to get out of the fibre, even though it does give a more even colour when crumbled… I also love the smell of Crottle which lingers for years, even with washing the fibre!
Just one really important thing about using lichen – I wonder if you could share this with your followers – it’s extremely slow growing and environmentally sensitive so caution and restraint is needed when gathering it. Only take a small bit from any one place, and preferably bits that have come lose from the rock. In many places lichen are endangered species (though thankfully not in the North of Scotland!) due to their intolerance of environmental pollution.
goprgeous colors. now i need to find some of those lichens 🙂
most interesting! thanks for sharing:)
the effect on different materials is amazing…