A Northwoods Almanac
for October 16 – 29, 2015 by John
Bates
"Another
equinox is tallied off and officially another summer ends . . . And now the
nights will have the smell and touch of frost and the days will have the crisp
leaf rustle of fall, the brown and yellow of another season's growth come to
maturity. That is the predominant note of Autumn: Maturity. Not death, nor even
hibernation. It brings a summing up, a sweetness in the apple and a ripeness in
the grain. Spring was a sprouting, an eager reaching for the sun, and Summer
was lush growth and blossom and the beginning of fruitfulness. But Autumn is
harvest, the maturity toward which the bud, the leaf, the blossom all reached
in their time.” Hal Borland,
Sundial of the Seasons
Snapping Turtles
Arlene Bozicnik sent a photo of a
baby snapper she found on 9/20. The hatchling had to dig itself out of the nest
and somehow know to head straight for the nearest water, even if it couldn’t
see it. But Arlene helped it on its way, placing it along a shoreline. Snapping turtle hatchlings are about the
size of a quarter and have temperature dependent sex determination, which means
that the sex of the turtle depends on the temperature at which the egg was
incubated – warm summers make more females, cooler summers more males.
The hatchlings typically live for
their first few years in shallow, heavily vegetated small streams where they
can reach the surface while standing on the bottom. As the turtles mature, they
migrate to ponds, rivers, marshes, and the shallow areas of large lakes to
establish their adult territory.
While some snapping
turtles may still be moving around now, they typically will have all have moved
to their hibernating areas by mid-October. In the winter, snappers hibernate in
shallow water, buried in the mud, where their body temperature is reduced to
about 34°F, or just above freezing. In the northern part of their range – our
area – they literally won’t breathe for more than six months, since ice covers
their hibernating sites for most of that time. They can, however, get oxygen by
pushing their heads out of the mud, which allows a gas exchange to take place
through the membranes of their mouths and throats, a process known as
extrapulmonary respiration.
Spring Peepers
Singing in October?
The peeps of male spring peepers
can still occasionally be heard this time of year. Unlike in the spring,
these calls are not coming from bodies of water but from the woods
nearby. And they are single peeps coming from individual peepers, not the
chorus of "sleigh bells" one hears in the spring. This
phenomenon occurs so regularly in the fall that herpetologists have given it
a name: the “fall echo.” They speculate that the calling of peepers
is spurred by light and temperature conditions, when fall climate
conditions are similar to those in spring.
Spring peepers will soon dig down
into the forest duff, burying themselves in a few inches of soil to wait out
the winter. Remarkably, they freeze, but they will thaw out one night in April
and begin again the pandemonium singing of males hoping to impress a mate.
Stacking Wood
Mary and I now buy our firewood
cut and split, but we still need to stack it, a task we accomplished over the
last few weekends. We bought almost entirely northern red oak this year, which is
about as good of firewood as one can find. It’s all about BTUs, or British
Thermal Units. One BTU is the amount of work needed
to raise the temperature of one pound of water by one degree Fahrenheit, or to
consume completely one four-inch wooden kitchen match. Here’s how
various northern tree species stack up, from best to worst, as millions of BTUs
per cord (note: different charts give different values, but the rankings are
usually the same):
Ironwood 26.8
Beech 24.0
Maple, sugar 24.0
Oak, red 24.0
Ash, white: 23.6
Birch, yellow 21.8
Birch, white 20.3
Maple, red 18.1
Pine, red 17.1
Spruce, black 15.9
Aspen, quaking 14.7
Pine, white 14.3
Basswood 13.5
Harris’s Sparrow
We’ve been
graced with two Harris’s sparrows at our feeders since 10/1, an unusual treat given
that they are uncommon migrants through our area. In summer, they breed in the
transition zone between the subarctic boreal forest and the low Arctic tundra
of northern Canada. They then leave their breeding grounds in late August and
arrive on their wintering grounds in the central Great Plains region in mid-November
to early December. They winter primarily from northern Nebraska and central
Iowa to Texas, but occasionally spend a winter in southern Wisconsin.
Because of
their remote breeding habitat and secretive nesting behavior, Harris’s sparrows
have been one of the last passerines in North America to have their nest and
eggs described. In fact, until recently, little was known about even the most
basic aspects of their breeding biology.
So whenever
we see them, we feel quite fortunate. They’re hanging out below our feeders
with a flock of other sparrows, including white-throated, white-crowned, and
fox sparrows.
The bird is
named after Edward Harris, a companion of John James Audubon on several of his
important ornithological expeditions, including in 1843 when Audubon ventured
into the far northwest via the Missouri River. Here is an excerpt from a letter
Harris wrote to a friend on 5/19/1843: “Since I wrote from Independence, the
most important event that has occurred has been my discovering a new Finch – a
larger bird than the white-crowned sparrow which it very much resembles . . .
but the head and throat are black with an ash-colored patch on each side of the
head.” A few days later, Harris wrote about their discovery of the western
meadowlark: “We have seen today the Arkansaw Flycatcher [a Say’s flycatcher]
and a Meadow Lark which must prove to be a new one, its note is so entirely
different from ours [the Eastern].”
Frost?
We had our first hard frost in Manitowish on 9/30,
perhaps the latest frost we’ve had in the 31 years we’ve lived here. Numerous
areas of the Northwoods, particularly those close to lakes, have yet to have a
frost. This is wonderful for ripening tomatoes, of course, but not so wonderful
for maintaining the biological integrity of our northern forest whose character
depends on cold weather.
We used to expect a frost
by August 20th at our home, and hauling green tomatoes indoors to
ripen was the norm. Now, we always get lots of red tomatoes and can pick them for
weeks on end. Our area is no longer a zone 3 for plants, but is now a zone 4,
and these late frosts are one of the results. Our late fall colors, often two
weeks later than the norm a few decades ago, are also part of the new mix.
Lady Bugs!
The downside to an extremely warm day in October (79
degrees last Sunday, 10/11) is the lady beetle invasion that inevitably occurs.
They came by the thousands to our home, showing up all at once as if they had
all read the same bus schedule. And in a manner of speaking, they did. If Asian
lady beetles want everyone to get together, they don’t text; they simply emit
aggregation pheromones, a chemical signal that must be a narcotic for them. In
response, the ladybugs gather in crowds on the south sides of houses that are
exposed to full sun. Here they crawl into cracks in walls or soffits, or find
gaps between sill plates and your foundation, then go into a hibernation-like
state called diapause and spend the winter enjoying the radiant heat your house
is losing. In diapause, insects can withstand subfreezing temperatures by
dropping their metabolism to as little as one-twentieth of their usual rate,
allowing them to survive on stored body fat.
Celestial Events
Venus, Mars and Jupiter all meet
up in the last week of October to present the closest grouping of the three
planets until January of 2021. You can also faintly see Mercury below this
planetary trio. Mars and Jupiter will share the same binocular field from about
October 12 to nearly the end of the month. Jupiter will catch up with Mars on October
17 to exhibit these two planets’ first conjunction since July 22, 2013. Then,
Jupiter will head toward Venus, showcasing their third and final conjunction of
the year on October 26. They’ll be like twin beacons before dawn. If you have
binoculars or a telescope, it’s fairly easy to see Jupiter’s four major moons.
The peak Orionid meteor shower
occurs during the pre-dawn on 10/21 and 10/22. The radiant point for the
Orionids is in the direction of the constellation Orion. The meteors often
don’t become visible until they are 30 degrees or so from their radiant point,
and since they will be streaking out from the radiant in all directions, the
meteors will appear in all parts of the sky. The Orionids are a relatively
modest shower, offering about 10 to 20 meteors per hour.
The full moon – the
Hunter’s moon – occurs on 10/27.
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