Day 65: Excerpts from a letter to Arnie:
"That sound you hear is me beating my head on the wall.
"Bruce
McCune's new books are making me painfully aware that there is
absolutely NO hope of making a positive field identification of any but
the most common lichens in the Park, and that probably 30-60% of our
herbarium specimens are misidentified.
"In trying to ID a
crustose species, I read what he had to say about Placopsis gelida, a
species growing adjacent to the specimen in question. As far as I can
tell, the only herbarium specimens of Placopsis taken from the Park have
all been identified as gelida, but according to McCune, that's probably
wrong. P. gelida is "a more northern species, rare s. of Canada." He
further goes on to state that the only way to tell it apart from P.
lambii is through TLC (thin-layer chromatography). (Right...now you know
what I want for Christmas next year...)
"Other species
require complex chemical tests to determine the presence of various
lichen substances...I
don't have the skills or the facility even if I did have the reagents,
and I doubt the Park's little lab is adequate to the task either.
"It
looks more and more like field work will just give you a 'best guess'
and maybe get your specimen in the right genus (or maybe not).
Otherwise, we're just bumbling along here and really can't tell what we
have in the Park. Crow is feeling very frustrated right now, and about
ready to go back to the 'Oh, look! Isn't that pretty!' level of
research."
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