Day 24: I've spoken in the past about "micro-ecologies," those little pockets where very specific conditions allow a species to survive, e.g., a sheltered bend on a streambank where sunlight falls only a few hours a day and snow fails to accumulate to any significant depth in winter, where soil pH and minerals meet tight criteria, and humidity is neither too high nor too low. Some plants are like Goldilocks: if it isn't "just right," it won't do. On a somewhat larger scale, an elevational change of a mere 500 feet can open a habitational window, limiting the range of some species while opening it up for different ones. Sometimes these species can be quite similar in appearance to their counterparts at higher or lower elevations, so it's always best to check and note important field characteristics for later identification. My hike to the Nisqually River yesterday yielded up two lichens I don't recall having seen previously. This one (Hypogymnia enteromorpha, or Budding Tube Lichen) caught my eye because it was more densely packed than those I find closer to home. Under scrutiny, I found its lobes demonstrated a tendency to bud along the margins rather than being exclusively dichotomously branched. Mentally noting small openings at the ends of the lobes and a black medullary ceiling led me to its identity, and I was able to leave it in the field, happy as Larry in its preferred environment.
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