No one really knows why
woodpeckers drill into utility poles. It is a fruitless endeavor for the
birds, since the kiln-dried, pressure-treated poles do not contain the
insects they seek with such staccato effort.
In
Canada, the problem is severe enough
that utilities affix metal owls to poles, trying to scare the
woodpeckers away.
Chicago
is not a woodpecker-rich environment, however, and so they aren't as
much of a threat to the 300,000 or so utility poles ComEd maintains in
the area. The poles ComEd uses range in height from 30 feet to 110 feet.
The shorter ones are made from southern yellow pine, the taller ones
from Douglas fir.
Nationwide, there are 100
million or so utility poles, with 3 million new ones installed each
year.
A tree needs to be about 35
years old to become a utility pole. The poles are dried and treated to
discourage insects and rot using one of three substances: creosote,
which dyes the poles blackish, or penta chlorophenol, which dyes them
greenish, or CCA, short for chromated copper arsenate, which also gives
poles a greenish cast.
The poles taper slightly -- 1
inch every 10 feet -- from the bottom, or "butt," toward the top. A
typical 40-foot pole weighs 1,272 pounds and will have 6 feet sunk into
the ground.
That 40-foot pole will set
you back about $300, delivered, and takes a crew of three 90 minutes to
plant, "if they're humping," said Carl Segneri, ComEd's vice president
of quality services.
A pole will last 80 years if
well-tended and 40 years if not.
"There may be poles in
Chicago
that are 75 years old," said Brent Gray, general manager of the Thomason
Company of Philadelphia,
Miss., one of the nation's top producers of
utility poles.
Despite the moisture, poles
do not -- as one might expect -- rot under the ground, because there's
no oxygen there, nor above ground, where there's air but less moisture,
but right at ground level.
Like much in the
communications business, the wood utility pole market is troubled --
"stagnant to shrinking," in Gray's words. Wood poles face three foes --
increasingly popular underground cable burial, high-tech microwave
transmission, and poles made of steel, concrete or fiberglass.
And, of course, woodpeckers.
"Woodpeckers have always been
a problem with poles,'' said Todd Shupe, professor of wood science at
LouisianaState
University's Ag Center in
Baton Rouge. "There's been a lot of speculation
as to why -- they like the noise, they're bored, they've got nothing
else to do? Who knows? But it's a serious problem."
I said it seems odd a
woodpecker could structurally undermine a telephone pole, and Shupe said
the problem isn't the hole itself, but that the anti-rot treatment only
seeps into the first few inches, not throughout the entire pole. So if
the woodpecker drills deep enough through the "treatment envelope," it
can expose untreated wood, inviting in termites, fungi and such.
While he had me, Professor
Shupe put in a plug for LSU's new utility pole initiative. Basically,
they're grinding up the old poles and constructing recycled hollow poles
as strong as regular poles.
"We are going to a pilot plan
right now," he said, noting that LSU has hired two new professors to
bring composite poles to the public in about a year.
At least now we have
something to look forward to.
Today's chuckle...
Early one
morning a foreman sent out two groups of workers to put up telephone
poles along a new highway, telling them to report at the end of the day.
The crews returned just as the sun was setting.
The
foreman asked the leader of the first group how many poles they
installed.
"Eleven,"
he said.
The
foreman patted the guy on the back and said, "Not bad."
Then he
asked the leader of the second group the same question.
"Two," he
said.
"Two! All
you installed were two?!" the foreman exclaimed, angrily. "The other
guys installed 11!"
"Yeah,"
the leader of the second group answered, "But you should have seen how
much they left sticking out!"
