I've reviewed a pamphlet on managing trees in order to encourage lichens, bryophytes and fungi here: http://www.permies.com/t/54169/books/Managing-trees-Scotland-open-habitats
Lichens contribute to a healthy, diverse habitat in two main ways, besides being intrinsically valuable, aesthetically appealing, and generally interesting.
* Some fix nitrogen and
* All provide food and shelter for microorganisms and invertebrates.
They also contribute to rock weathering and thus soil formation: just how fast this is depends on the rock, the lichen and the habitat.
A few may have adverse effects on trees but, given that healthy forest habitats are often dripping with lichens, this can't be a major problem. It's possible some may have symbiotic relationships with higher plants, but this is a new subject for research, and I don't know anything about it.
A diverse Permaculture habitat may provide conditions for many different species.
I've learned a few tips and tricks for encouraging lichens, but haven't tried any myself.
Basically, some people think that painting suitable nutrients on the right substrate will help get them started:
* cow or sheep manure mixed with water
* horse urine
* rice water
* various combinations of the above
I don't know how quickly this is just going to wash off, so it might work best in areas where there is limited rainfall for part of the year, allowing spores to adhere to the surface, but this is probably something you'd need to experiment with, unless someone can find evidence from someone who's tried it. Lichen lovers recommend painting or spraying just before a rainy season, and have their own tried and tested mix, which they call Formula 29: http://lichenlovers.org/lichen_growth_formula.phtml They also explain the theory of how this works.
Mixing in scraped lichen from another source might help you to propagate lichens. Many can cope with extended periods of desiccation (although they often prefer humidity).
It might also help if you matched the acidity of the mix to the acidity of the substrate to encourage the right lichens for the substrate. Many lichens are limited by the acidity of the substrate on which they grow. According to the British Lichen Society:
* larch and pines (down to pH 3.2)
* birch and oak (pH 3.8-5.8)
* rowan, alder, beech, lime and ash (pH 5.2-6.6),
* elder, sycamore and field maple, apple, poplar, willow and elm (pH 4.7-7.1).
I haven't been able to find figures for fruit trees other than apples, but I suppose scraping the bark surface, powdering it and mixing it with distilled water might give you a figure (but this is guesswork: if anyone has a better method this would be good).
Does anyone have experience with this? Any more tips and tricks?
Rebecca Norman wrote:What does your lichen growth formula consist of? I'd love to do this. I've heard of putting yogurt, water and lichen in the blender and painting onto rocks, but I'd rather know what you did that actually worked.
1 pint milk
1 teaspoon flour
1 teaspoon yeast
1/2 teaspoon gelatin
1 tablespoon green algae powder
(These days, I would add 1 tablespoon of dried mushroom powder)
1/16 teaspoon water soluble fertilizer
Bring almost to boil, cool to body temperature or below. Then add:
2 teaspoons of lichen flakes collected from common lichens growing in a similar microenvironment to where the new lichens are wanted.
2 teaspoons of healthy soil collected from an area near where lichens are currently growing.
Use a paintbrush to apply to rocks or trees. Additionally, I placed lichen covered rocks on top of the cement blocks hoping that they would shed some propagules.
Growing lichens is an interesting study in patience...
Just wanted to mention to all those who like edible forest gardens, that many lichens are edible also.
The only thing to watch out for is to avoid all yellow, or yellowy (orange) species,
as they may contain poisonous levels of vulpinic acid or usnic acid (both of which are yellow).
for rocks are rock tripe (which is black), Parmotrema perlatum )whic
for ground iceland moss
and reindeer moss (which is white) though note if it gets much sun exposure it accumulated usnic acid.
for trees Wila (brown versions) mostly in humid mountains,
also likely any white/green/black lichens should be fine also.
generally since they are so slow growing they are a delicacy,
but still if you manage to grow a large amount it can become a regular spice.
For most of them it seems best to cook in order to make it easier to absorb,
so as a spice to add to raw ingredients of soups, stir fries and other cooked dishes.
Another thing to note is that the environment affects all plants/lichen,
so even if it is a suitable color but growing in a toxic environment,
or on a poisonous tree (yew) then it would be best to avoid it.
Lichen is also a good pollution indicator:
Lecanora conizaeoides typically looks like green pots filled with yellow,
it can grow in very high pollution environments. I'd avoid eating them.
Lepraria incana looks overall pale green and fuzzy,
it can grow with high pollution.
Hypogymnia physodes and/or Parmelia saxatilis or P. sulcata are pale green with branching "leaves",
these can grow in moderate pollution, and would probably be the first level safe to eat.
Usnea ceratina a green hair like lichen appears in fairly low pollution environments,
these hair-like ones are likely as good as Wila to eat, and increase the growing area by extending outwards,
so if you can, certainly do grow them.
As a final note, I think there can be a time and a place for yellow lichen,
such as places which you don't want animals to eat, or don't want yourself to accidentally consume.
One idea for it is around the trunks of young saplings, as an alternative to other winter protection schemes.
Another would be to grow in known toxic areas, such as where there were chemical spills.
it is similar to the yellow of caution tape, but longer term and self-renewing.
 Lichens for food https://en.wikipedia.org/wiki/Ethnolichenology#Lichens_for_food
 Lichens for air quality http://www.air-quality.org.uk/19.php
Anne Christgau wrote:Hello from across the pond,
At our local park in South East London lichen can be seen growing on the tarmac paths
At first I thought I was looking at gobs of chewing gum, on closer inspection lo and
I'm on your side of the pond, but from Beyond the Wall.
This is actually known as Chewing Gum Lichen (Lecanora muralis to us geeks). It grows just outside my front door.
I love lichens and photograph them wherever I travel. I have a few guide books on them and choose not to eat them because I feel they grow to slowly and that's not sustainable. I feel they're better left alone. I did just cut up a birch tree that was quite old and rotten and had to be removed. I saved some of the logs because they were covered in several lichen species/varieties. I am not sure what to do with the logs yet, but so far they're just sitting upright in the woods. I want to put them somewhere that they can continue to live until the bark rots away (and with birch that could be a while!)
How a Guy From a Montana Trailer Park Overturned 150 Years of Biology
Sensational title aside, it's a lovely alternative education story combined with loads of juicy lichen science. The science being how lichen is not just the symbiosis of only one fungi and one alga, but often (usually? sorry, too much skimming here) two fungi. It also seemed to indicate that the word symbiosis originated in the study of lichen.
And the guy in the story is from Montana.
Here is the link to the actual research: