Here At Lichen Labs...

Day 1 of Year Six: Yes, I've decided to continue 365 Caws for another year if the Fates and Google will allow. Hard to believe I've been at this project for five years already. So, without further ado...

Here at Lichen Labs, we have entered a new phase in the tricky business of lichen identification, i.e., chemical testing. There are only a few qualifying reagents available to the home scientist, among them household bleach (the "C test") and caustic soda, aka lye (the "K test"). Both need to be handled with care to prevent chemical burns or degradation of materials from accidental contact.

To perform the tests, a small amount of reagent is applied to a specific section of lichen and then the tissue is examined under a microscope in order to observe any changes in colour. Even the simplest test can be useful in separating one genus from another, perhaps even one species from another. More sophisticated tests can be performed in a professional laboratory if one is available. Of course, a well-trained observer may be able to differentiate species by eye, but for the neophyte, a determination confirmed by chemical means is always best.