Wednesday, December 29, 2010

Orion

Nature Watch
By Susan Thurn,
Cable Natural History Museum

The longest nights of the year are upon us, but at least we’re past the solstice and days begin lengthening again. With the addition of a new dog in our family, I find myself outdoors at night more often than previously. These walks are pleasurable for in spite of the cold, there is an amazing night sky to greet me. Even in early evening, sky-watching is worthwhile, as Orion, a constellation we see only in the winter, is peeking into view as night falls. Sirius, the brightest star in our night sky, also sparkles in the south. It makes for a lovely view!

Orion, known in historical legend as the hunter, shines in prime time during winter's long nights. It can be viewed in the east soon after nightfall. It is perhaps one of the most easily found and identified constellations we can view. Bright stars make up Orion’s three-star belt. Around the belt at similar distances are four bright stars that make up the outline of the hunter’s body. An orange star named Betelgeuse is Orion’s left shoulder, and a blue star named Rigel is brightly showing Orion’s right foot. Moving down from the belt is a small line of three stars that create the hunter’s sword, although technically the middle star is not a star but the Orion Nebula, which can be seen with binoculars as a glowing cloud of material. Sirius, the bright star to the south, is part of Canis Major, the big dog or big dipper.

Orion, the hunter, stands by other night constellations such as the river Eridanus, is accompanied by his faithful dogs, Canis Major and Canis Minor. Together they are said to hunt celestial animals such as Lepus, the rabbit, and Taurus, the bull. There are many stories in different cultures of how Orion came to be in our night sky with his dogs. In Greek mythology, Orion was in love with Metrope, a seven sister who forms the Pleiades constellation. Unfortunately, Metrope did not return his affections. Orion’s tragic life ended when he stepped on the scorpion, Scorpius. The gods then felt badly for him and put him and his dogs in the night sky, along with animals he could continue to hunt. However, Scorpius was placed far away from Orion in the night sky so that Orion could not be hurt again. Hungarian tradition also calls him a hunter, but believes that he is the father of Hungarians. The Chinese thought the three stars were a top a man’s head. Australian aboriginals believe Orion is called Julpan, a canoe. They tell the story of two brothers who went fishing, and caught and ate a forbidden fish. Seeing this, the sun sent a waterspout that carried the two brothers and their canoe up into the sky. Native Americans from a tribe in California thought that the three stars were the footprints of the god of the flea people. This legend states that when his five wives ran away because they were itchy, three times the god of the flea people looked in the sky for them. When his footprints are seen only in the winter months, the flea people go into hiding, a time when there were no fleas. Sumerians thought the pattern was a sheep, and Betelgeuse, meaning armpit, was the armpit of the sheep.

There is more than just Orion to take a peek at in our night sky this time of year. On December 29, the thin crescent moon rises in the southeast with the planet Venus to its lower left. Our Christmas star, Sirius, rises around 7-8 p.m. and is worth looking at with binoculars, as when it’s low in the sky it twinkles in flashing colors. In early January, Uranus and Jupiter can be viewed with binoculars. These are all sights worth getting outdoors in your own back yard!


For over 42 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Thursday, December 23, 2010

Balsam Fir

Nature Watch
By Susan Thurn,
Cable Natural History Museum

As we head into one of our biggest holiday weeks, some of my most favorite sights and smells include the lights and the smell of our holiday tree, a beautiful balsam fir. The history of the Christmas tree has many interesting and different stories. The Egyptians might not have celebrated a holiday with a fir or pine, but were part of a long line of cultures that treasured and worshipped evergreens. In fact, when winter solstice arrived, they brought green date palm leaves indoors to symbolize life's triumph over death.

Another balsam fir holiday story is associated with a German, St. Boniface, who cut down an oak tree in order to disprove the legitimacy of the Norse gods to the local German tribe, and was amazed when a fir tree sprung up from the roots of the oak. Another cultural tradition included a tree that was taken to the town market center and lit aflame to celebrate the holidays. Yet another story of the tree includes the decoration of a small tree with nuts, apples, pretzels and paper flowers for the children. Germans and Scandinavians placed evergreen trees inside their homes or just outside their doors to show their hope in the forthcoming spring. No matter what the celebration, today the balsam fir is still a perfect tree as it has the benefit of not shedding its needles when they dry out, as well as retaining good color and scent.

What is special about balsam fir? It’s a great tree to shake hands with, with very soft, individual flat needles. Balsam fir bark is thin, gray, and smooth except for numerous blisters on younger trees. The scientific name "balsamea" is so named because of the many resinous blisters found in the bark. These balsam blisters contain a sticky, fragrant, liquid resin and so they are sometimes called “blister pine.”

A balsam fir provides food and cover for red squirrels, moose, snowshoe hares, deer, ruffed grouse, crossbills, and chickadees. The needles are also eaten by some caterpillars. Porcupines eat the seeds.

The balsam resin has been used to produce Canada balsam, a type of turpentine, and was used as a glue for glasses, optical instruments, and for preparing microscope mounts. It has also been used as a cold remedy and an EPA approved nontoxic rodent repellent. It is a tree of many uses!

I don’t have to enjoy the tree in my living room, as balsam fir grows commonly in the forests around us. Be sure to get outdoors this holiday season and shake hands with a balsam fir!

For over 42 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Wednesday, December 15, 2010

Mistletoe

Nature Watch
By Susan Thurn,
Cable Natural History Museum


Having just celebrated six months of wedded bliss, this holiday season brings on great feelings of love and opportunity for family celebration. It is a time filled with candy canes, colored tree lights, and mistletoe, just a bit of the many things we can enjoy at the holidays. I’ll never forget the time I was preparing a lesson plan for area schools on symbiosis, a word that describes the relationships between organisms in the natural world. I discovered then that mistletoe is a parasite. Mistletoe, a parasite? I always thought it was so ironic that a plant that brings love and joy into our lives was also a plant that uses other plants as a host by taking nutrients out of the tree. What a surprise!

Mistletoe is a partial parasite, as the plant is still capable of photosynthesis. They have a special root system, called haustoria, which grow down into their hosts. They extract nutrients from the trees upon which they grow.

The common dwarf mistletoe grows in northern Wisconsin. Not looking like most mistletoe plants we hang in our homes, this dwarf plant grows less than 3 centimeters tall. In spite of its size it often causes a very conspicuous irregular growth known as a “witch’s broom.” A witch’s broom is created by the mistletoe as it causes the tree to grow a compact mass of branches that resemble a broom that can reach 3-10 feet in size. Its main host is black spruce, but it also will parasitize red, white, and jack pine and balsam fir.

To some, mistletoe might be considered a negative part of a forest, but actually mistletoe does have some benefits in many ecosystems. The density of the growth can provide habitat to birds and other animals. Some species of mistletoe can cause the host plant to grow more berries, increasing reproductive success and providing food to other animals.

Mistletoe has a history that is rich in human tradition that goes all the way back to Greek culture. Throughout time mistletoe was thought to bestow life, protect against poison, and increase fertility. It was also thought to ward off evil, or bring peace, as well as provide a prediction of happiness and long life. Mistletoe can certainly bring magic to this season’s holiday joy. May you all enjoy a wonderful, festive holiday, and be sure to find your way under the mistletoe!

For over 42 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Wednesday, December 8, 2010

Barred Owl

Nature Watch

By Susan Thurn,
Cable Natural History Museum

I’ll never forget the time I called in a barred owl using my voice, only to have both the owl and myself experience being dive-bombed by woodpeckers. Or the other time I called in five owls all part of the neighborhood around the house. I’ve been practicing a barred owl call for many years now, and its who-cooks-for-you song is noticeable enough in the forest to make it one of the most-known owls in our northwoods environment. It is with constant amazement and utter respect that I interact with these birds in our area.

A barred owl enjoys a variety of habitats that include deep, moist forested areas, wooded swamps and woodlands near wetland areas, preferring larger forest tracts. Their territory is thought to be up to one square mile of land. Barred owls eat small mammals such as voles, mice, shrews, squirrels, rabbits, and chipmunks. They also will eat birds up to the size of a grouse, woodpeckers, and even smaller owls, and are known to take prey from around bird feeders. They catch birds as prey at dusk when the birds are settling in to roost for the night, as the barred owl cannot usually take them while in flight. They also will eat bats, snakes, frogs, salamanders, mollusks, and insects. They have even been observed wading in water in search of crayfish and fish. In fact, the feathers on the front belly of the barred owl can sometimes have a pink tinge, possibly due to eating crayfish. In winter, barred owls rely on their excellent hearing to focus in on animals burrowing through snow.

Barred owls hunt mostly at dusk and night-time by sitting on a high perch and looking and listening for prey. They then catch their prey during a short flight to the ground. During the day they hide in dense foliage, usually high above us. They also roost on a branch close to the trunk, or in a natural tree hold.

A very territorial bird, barred owls use vocalizations that are more extensive than their familiar who-cooks-for-you. When feeling very territorial, they move from a short bark into a monkey-like call that is amazing to hear. To me these owls represent one of the best creatures of the northwoods. Their beauty, their night call, are all worthy of admiration.

For over 42 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Thursday, December 2, 2010

White/Black Fur

Nature Watch
December 3, 2010
By Susan Thurn,
Cable Natural History Museum


If the color black absorbs heat, why is a polar bear white? It turns out that dark or black fur isn’t always the warmest fur to have. Energy does come to animals when the sun is shining. This solar radiation penetrates into the fur, some of which is absorbed at the surface, and some all the way to the skin.

Because our winters have less sun, we have less incoming solar radiation, called insolation. Animals living in our region and latitude are exposed to a lower amount of insolation. Black fur absorbs solar radiation well, but even then, much of the energy is redirected back into the environment again, keeping the sun’s heat from reaching the animal’s skin. A contrast to this is white fur, which reflects some sunlight outward, but also reflects the sun down into the fur layer down to the skin. Add to this the thickness of the fur and how those fur pieces lay over each other, this white fur can more successfully warm the skin. Animals that have dark skin with white fur (as do polar bears) increase their ability to absorb heat. How interesting that white fur is not just about camouflage!

How do humans deal with constant exposure to cold? Can we, who live in the northwoods, ever get “used to the cold”? Evidence does show that humans can acclimatize themselves to colder environments, but usually only with prolonged exposures to that cold. Several groups of people have developed very specific adaptations to cold. Inuits, Norwegian fisherman, and Tibetan and Indian yogis have increased circulation and skin temperature in their extremities. Finnish outdoorsmen can have brown fat in strategic locations. Mailmen of Quebec City have lowered blood pressure and heart rates. Antarctic workers have a higher core temperature. Those with yoga training can exhibit a higher cold tolerance.

Sign me up for the next yoga class! And the next time I feel bad about the extra layers of fat around my body, I’ll just think of it as strategically located cold insulators. Whatever it takes, being outdoors, even in the cold, is worth making some adaptations!

For over 42 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.