Locust tree fungus (0/1)

Beverly Erlebacher bae at
Thu Feb 6 12:11:13 EST 2003

In article <r9rt3vcuc14k4qocqdj2lqedras1s32jbd at>,
 <intercon at> wrote:
>I have a couple of groves of flowering locust trees (don't know there
>official name).  I was just noticing that the north side of this grove
>of trees is covered in a greenish/yellowish fungus or mold.  I took
>some digital pictures that I am attaching to see if anyone can tell me
>whether this is a benign fungus or something to take action on.  If I
>am to take action, what should I do?
>Thank you....

Your picture, being a binary, didn't make it here.  You don't tell us
what climate you live in, but it's pretty common for "stuff" to grow on
the shaded side of trees, which is the north side in the northern
hemisphere.  This is the source of the boy scout or literary proverb
about finding north when lost in a forest.

In a really moist climate, the "stuff" may be actual moss, but in less
humid areas it's likely algae, in particular Protococcus IIRC, which
may no longer be officially an alga, but rather a cyanobacterium.  In
either case, it's completely harmless and natural, so just enjoy it for
the way it enhances the natural beauty of your groves.  It's just using
the dead outer surface of the bark for support.

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