Day 145: Far be it from me to miss an opportunity which literally falls from above, so when the combination of wind and snow dropped a long, heavy fir branch in my yard, I simply had to check it for lichens. I was hoping for Kidneys, but no such luck. I settled instead for a chance to improve my skills at identifying Usneas. I made a little checklist, and if you flinch at my flood of weaving terminology, you should probably quit right here, because we're diving into a whole 'nother language which includes isidia, soralia, medulla, cortex, axis, fibrils, papillae, foveation, annular rings and stereomes. With a hand lens trained on a rather dry specimen, I marked off presence/absence, colour, shape and UV reaction until I had narrowed the field down to two: pacificana and subfloridana. Although I would have preferred to have a fully hydrated subject in hand, the ratio of thickness between cortex, medulla and axis suggested Usnea pacificana. As always, I reserve the right to be wrong, because both species are common in western Washington at this elevation.
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