""Most lichen are likable, but not exactly consumer friendly. What the lichen all share is acid and as such require proper preparation if they are to be eaten because unprepared and uncooked they will painfully attack your digestive track. Unprepared lichen taste like aspirin. That should motivate you to prepare it correctly. Never eat unprepared and raw lichen unless your life truly depends upon it.  It probably will not kill you but you will wish it had.""

Everything you need to know about lichen:
What's not to Lichen?