Night walk - Fall
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Welcome to a night walk at the Penquis virtual nature center. It's fall. The leaves are turning
color and dropping from the trees. We may not hear much tonight, but we can talk about things.
Such as leaves. Ever wonder why they change color and drop? Well, with the shortening days, the
chlorophyll, the green material that performs the photosynthesis, dies. Starch is withdrawn
toward the roots to feed the tree until spring, and what remains is colorful in some species. That
color has always been there; it just doesn't show until the chlorophyll goes away. Then a layer
of tissue forms where the leaf stem joins the twig. It's called the abscission layer, but don't
worry about that. It's purpose is to prevent the loss of moisture from the plant. Once that's
formed, the leaf drops off.
Well, we really aren't hearing much. It's getting sort of chilly, and there isn't much to
smell at this time of year. Only the asters and daisies are still blooming, and they don't
have much scent. Oh, check out this leaf. It is one of the recent casualties of approaching
winter. Feel the shape, sort of hand-shaped. Count the lobes. Those little projections near
the base count as lobes. Five. And the edges are smooth, except for some large, pointed teeth that
may even feel like secondary lobes. Sugar maple. Red maple generally has three lobes and
lots of small teeth. Norway maple which is planted on our streets has usually seven lobes and
feels like sugar maple on the margins.
OK, do you want to continue on, or head back inside?
Glad you stayed. Let's have a listen. It's pretty faint, but you can hear a twittering overhead.
You probably thought it was your ears. It's flocks of migrating birds. I know people who could
stand here and tell you what species were migrating overhead right now. At least, they say they
can. I have no way of checking. Oh, wait! There is one we can all
identify. (DVG) Canada geese heading south. I guess any hope we may have had that mother nature
was kidding us about winter coming goes south with them.
Stand quietly. Let your mouth open just a bit. It helps you locate sound. Oh, is that a sort of
grunting and groaning I hear? That might be a porcupine. It's rutting season for them, and they
make that sort of sound. Bad news for our hemlocks. They can strip a tree pretty quick. Not
much preys on porcupines but fishers, and they are rare around here.
What did you say? You heard else from that direction? Yes, I hear it,
too. (long)(WK) Good going. I guess there are a few bullfrogs that haven't settled down
for the winter yet.
Hey, there's something else lingering on! The loons move to the coast
and on south for the winter. The ponds freeze up, and they can't live on them. Incidentally,
most people don't recognize loons during the winter. That fancy black and white plumage turns
dull shades of gray and white. Doesn't help much to bird by ear at that time, either. They
rarely say anything. They are really common at the coast, though.
And there is our owl. Recognize him? Great horned owl. They are the
first to breed of the owls. This one is already setting up shop. Well, it is chilly, and
I doubt we are going to hear more tonight. Thanks for coming.