Friday, February 28, 2014

Conference Time

This next week I will be busy attending conferences.  Tomorrow I will be attending (and helping to run a booth) the Quiet Water Symposium.  The following two days I will be at the Wildflower Association of Michigan (WAM) annual conference.  Then on Friday and Saturday of next week I will be attending the Michigan Science Teachers Association (MSTA) conference. 

I really enjoy all three of these conferences, but my favorite is the WAM conference.  Of all the conferences and workshops that I have attended over the last few years, I always learn the most at the WAM conference.  The focus the last few years has leaned heavily toward using native plants to attract and conserve populations of pollinators.  This is something that I feel very strongly about.  I have written several times about the relationships between pollinators and host plants, about gardening for Monarch butterflies, and about native pollinator gardens in general.

I thought I would share a photo from one of the four native pollinator gardens that I have helped install in the local area.  This garden is located at Winn Elementary and was planted two years ago.  2014 will be its third Summer and I can hardly wait to see how the garden will take off this year.

Thursday, February 27, 2014

Good deer, bad deer - A Cartoon from 1960

Last week I shared a cartoon by Oscar "Ozz" Warbach from the January - February 1961 issue of Michigan Conservation.

I thought I would share another Ozz Warbach cartoon from Michigan Conservation (March-April 1960).

One of the biggest complaints that we hear in our office is about wildlife damaging crops and other plants.  At the same time, many of the programs that we work on in our office are designed to help wildlife by improving habitat.  As illustrated by Mr. Warbach, the issue was much the same 50 years ago.

Wednesday, February 26, 2014

A scene from Summer (26 AUG 2013)

I thought I would share a picture from exactly six months ago to remind you of Summer.

Ants and aphids

This photo shows a Common Milkweed (Asclepias syriaca) plant in a field near Mt. Pleasant.  This milkweed was covered with hundred of small aphids.  The aphids were being guarded by a number of ants.  The ants protect the aphids from predators and are rewarded with a sugary substance (honeydew) that is secreted by the aphids as they feed on the plant.

Summer will be here before we know it.

It's only 22 more days until the Vernal Equinox, 111 days to the Summer Solstice, 209 days to the Autumnal Equinox, and only 298 days until the Winter begins again.

Enjoy each season while it is here.

Monday, February 24, 2014

A case of mistaken identity...

I make mistakes.

We all do.  Sometimes due to lack of care.  Sometimes due to lack of information.

One of my biggest mistakes is misidentification.  Often, when I find myself looking back at the photographs on my computer, I will find that I have made mistakes when naming the flowers that I photographed.  I found another one yesterday.

Aster identification can be confusing.

This flower has been misidentified on my computer files since September 2008.  I have variously listed it as a Small White Aster (Symphyotrichum racemosum), Panicled Aster (Symphyotrichum lanceolatum), and Heath Aster (Symphyotrichum ericoides).

Turns out that each of those identifications was wrong - each for different reasons.

Small White Aster (S. racemosum) is not found in Michigan.  Whoops!

Panicled Aster (S. lanceolatum), which is also know as Tall White Aster or White Field Aster, does grow in Michigan, but a close look at the photo shows that the leaves of this plant are wrong for a Panicled Aster.  The leaves of a Panicled Aster would be longer, wider, and hairless.

The same close-up also shows why this plant is not likely to be a Heath Aster (S. ericoides).  Heath Aster, which is also known as Many-flowered Aster, does grow in Michigan, but these flowers have too many petals to be a Heath Aster.  A Heath Aster Flower will have between 8 and 20 petals, with around 12 petals being the average.  Each of these flowers has twenty or more petals.

This leads me to identify the plant in these photos as the Frost Aster (Symphyotrichum pilosum).  Based on the information available to me, this is the best identification that I can come up with.

Frost Aster (Symphyotrichum pilosum)- image from September 2008 at Mill Pond Park in Mt. Pleasant, MI

So how did I come to realize that my identification was incorrect?  I started looking at the many books on my shelves.  I also started looking on the internet.  Some of the websites that I find most useful for wildflower identification include the USDA PLANTS database, the Ladybird Johnson Wildflower Center database, the Illinois Wildflowers website run by Dr. John Hilty, the University of Wisconsin-Stevens Point Wildflowers of Wisconsin database, and the Minnesota Wildflowers Information database.

Friday, February 21, 2014

Native Species Profile - Nodding Trillium

Despite the current weather, Spring is not far away.  With the arrival of Spring, wildflowers will not be far behind.  Although a few flowers will begin blooming as early as late February - I'm talking about you, Skunk Cabbage - the main bloom of Spring ephemerals will peak between the third week of April and the second week of May. 

One of my favorite spring wildflowers is the Nodding Trillium (Trillium cernuum).  Most Trillium species are known for their large showy blooms that rise above the plants whorl of three leaves.  Of these, the Large-flowered Trillium (Trillium grandiflorum) is the showiest and most well known.  Their large white blooms can be seen from a great distance in the Spring woodland.

The large showy flower of a Large-flowered Trillium

The Nodding Trillium is different.  Like other trilliums, it sports a whorl of three leaves.  It also has flowers with three petals and three sepals.  However, instead of having a flower that rises above its leaves, the flower on the Nodding Trillium is hidden on a stalk that droops below the leaves.  The opening of the flower points down toward the ground. 

The cernuum in Trillium cernuum means "nodding or drooping" in Latin.  Although the plant can grow quite large (6 - 24 inches tall), this drooping habit makes these flowers much harder to spot in the woods than other species of trilliums.  To really see this flower you have to get down on the ground and look up at it.

Despite being hidden, the flower of the Nodding Trillium is quite large - up to 1.5 inches across.  The three sepals are green and the three petals are white.  Both the sepals and petals curl upward, exposing the flower's pistil and six stamen.  The pollen covered anthers (tips of the stamen) are pink-purple colored.  This anther color is one of the identifying marks of this flower and distinguishes it from the similar looking Drooping Trillium (T. flexipes) which bears white anthers.

Nodding Trillium - not the up-curled petals and pinkish-purple anthers
Like other Trillium species, Nodding Trillium often forms wide colonies of plants.  The colonies probably spread outward by the activities of ants which carry the seeds into their burrows to consume a fleshy coating on the seeds before discarding the hard seeds in their midden (garbage) piles.  The colony of nodding trillium that I have been observing for  several years has probably doubled or tripled in size since I discovered it.

Part of a colony of Nodding Trillium

The Nodding Trillium prefers a more damp habitat than the Large-flowered Trillium.  While the Large-flowered Trillium grows in rich, moist deciduous woodlands, the Nodding Trillium prefers cool wet woods like the borders of swamps and floodplains.  It is listed by the USDA as a Faculative Wetland species - meaning it is usually found in wetlands, but may occur in upland habitats.  The USDA lists the Nodding Trillium as occurring in 22 northeastern states (south as far as Virginia and reaching west as far as the eastern counties in the Dakotas) and across Canada from Newfoundland to Saskatchewan.

Nodding Trillium - note the white flower drooping below the whorl of three leaves.

Across its range, Nodding Trillium blooms between May and late-June.  In Mid-Michigan, I can usually find it blooming during the first or second week of May.  In any patch of Nodding Trillium, it is typically only the largest plants which bloom.  Producing flowers (and fruit) requires a large expenditure of energy and it may take several years for a plant to store up enough energy to produce a bloom.

Nodding Trillium - note the upturned petals and purple anthers

After the flowers are pollinated, a bright red fruit develops.  This fruit will be oval-shaped and up to 1 1/8 inches long.  This fruit will commonly persist on the plant into early fall. I commonly find them in September.

Nodding Trillium leaves and fruit

Nodding Trillium fruit

Basic Information

Nodding Trillium 
Trillium cernuum

Height:  6-24” tall

Habitat:  wet deciduous woods

Flower Color:  white

Bloom Time:  May –late June

Thursday, February 20, 2014

Feeding Birds in Winter - A Cartoon from 1961

I love old science and nature magazines and books.  Although some of the information in them is outdated, the illustrations are often better than those found in newer magazine.  Among my collection of old books and magazines are several issues of Michigan Conservation from the 1950s and 60s.  One of the best things about the old issues of Michigan Conservation are the cartoons by Oscar "Ozz" Warbach.  Ozz was a trained biologist who used his cartoons to teach people about nature and wildlife.  Among other positions, he worked as a "conservation illustrator" for the Michigan Department of Conservation from 1954 to 1977.  The Michigan Department of Natural Resources still sells a book of Ozz's illustrations titled Mother Nature's Michigan.

This cartoon about feeding birds appeared in the January-February 1961 issue of Michigan Conservation.

Wednesday, February 19, 2014

Soil Particle Sizes - Sand, Silt, and Clay

One of the programs that I do with students is called "Soil Science".  In this program we discuss the different materials that make up soil (minerals, organic matter, water, air, etc.) and the idea that soil particles come in different sizes.  To show that soil particles come in different sizes, the students perform two different experiments.

In the first experiment, the students perform a sedimentation test.  In this test, a sample of soil is placed in a plastic test tube.  A small amount of ammonium aluminum sulfate (also called ammonium alum or just alum) is added to the test tube.  The alum bonds to any organic matter in the soil.  Then the test tube is filled with water and capped.  The students then vigorously shake the test tube for about 30 second to a minute before placing it in a rack for 15 to 20 minutes.  During this time the soil that was mixed with the water settles.  The larger (heavier) particles sink faster than the smaller (lighter) particles.  This means that the soil will settle into distinct layers based on size.  The bottom layer will consist of sand particles of varying sizes.  This will be topped by a layer of silt.  Finally, if we allow the sample to sit long enough a layer of clay particles will settle on top of the silt - the clay usually is still suspended in the water after 20 minutes and may take as long as 24 hours to fully settle out.  Any small particles of organic matter in the soil will float to the top of the test tube - the alum bonds to the organic matter and helps it float.

The second experiment that the students perform involves sorting soil particles with the use of a sieve.  The sieve that we use has a series of 4 mesh screens of decreasing diameter.  These screens allow the students to separate the soil into five different parts by size.  The first screen removes any large particles from the soil (pebbles/gravel/etc.).  The next three screens sort out sand particle of varying sizes - coarse, medium, and fine.  The soil that remains at the bottom of the sieve is a combination of  silt and clay (and possible some very fine sand particles).  The sand particles all have that familiar "gritty" texture that can be felt between your fingertips.  The combination of silt and clay, when just touched has a fluffy texture like flour, but if you take a small amount between your finger and thumb it will feel "slippery" when rubbed together.

So what do these particles look like?  When magnified the difference in size is quite astounding. 

First up is the coarse sand.  These particles are quite large.  The first image shows the coarse sand with only front lighting.  The sand is composed of particles of several different minerals of varying colors.

Coarse Sand - 2X magnification
The second image shows the same particles with back-lighting.  The particles are large enough that most of them are opaque - meaning you cannot see light shining through them.

Coarse Sand with back-lighting - 2X magification
The next two images are of a medium grain sand. These particles are about 1/4 to 1/2 the size of the coarse sand.  The first image shows the sand with front-lighting only.  Again the sand is composed of several different mineral types.  The second image shows the same sample with back-lighting.  In this image, most of the grains are small enough that they are now translucent - meaning light shows through them.  Another difference from the coarse sand is that while the coarse sand was quite angular, most of the edges on the medium grain sand have been rounded off.

Medium Grain Sand - 2X magnification

Medium Grain Sand with back-lighting - 2X magnification
The next two images are of a fine grain sand.  The grains here are about 1/4 to 1/2 the size for the medium grain sand and about 1/16 to 1/8 the size for the coarse sand.  Again the different minerals can be differentiated based on color.

Fine Grain Sand - 2X magnification
At this size, all but the darkest particles are translucent when back-lit.

Fine Grain Sand with back-lighting - 2X magnification

The final two images show a combination of silt and clay.  There are also a few very-fine grain sand particles in this sample (the largest particles).  The clay is best seen in the second image as very small black dots against the back-lighting.

Very-fine Sand, Silt and Clay - 2X magnification
Very-fine Sand, Silt and Clay with back-lighting - 2X magnification.  The clay appears as very small black dots in this image.
As you can see from these image (all taken at the same level of magnification) there is a great degree of difference in the size of soil particle from the largest to the smallest.  One way to think about this size difference is this:  Imagine if a particle of sand were the size of a basketball; at this scale a particle of silt would be the size of a softball; and a particle of clay would only be about the size of a golf ball.

UPDATE (12MAY 2015):

I recently did a follow-up to this post showing the results of the soil sedimentation experiment detailed above.  Check it out here.

Tuesday, February 18, 2014

When will the snow and ice finally melt?

It snowed again last night and local schools cancelled classes again. 

Snow on February 17th is not unusual.  What has been unusual is the amount of snow that has fallen across the United States this Winter and the cold temperatures that have persisted across much of the country.  Many cities are experiencing some of their highest snowfall amounts on record and some of their coldest temperatures on record.  This means that much of the snow that has fallen since the beginning of December remains on the ground - we have not had our typical cycle of repeated snowfall followed by melting. 

This presents an interesting question. 

When will the last snow and ice melt this Spring?

My last photos of snow and ice from the Spring of 2013 dates to April 23rd.

Unless we have an unusually warm Spring, I expect that I may be able to find some remaining ice as late as May 1st.  I guess I will have to wait and see.

Friday, February 14, 2014

A Natural Valentine

My Valentine to you.

The heart shaped flowers of Dicentra canadensis (better known as Squirrel Corn)

Thursday, February 13, 2014

Public Events - MAY and JUNE 2014

I have several public events coming up later this year in and around Mt. Pleasant.  Be sure to mark these on your calendar.

May 3rd          Celebrate International Migratory Bird Day at the Ziibiwing Center (6650 E. Broadway, Mt. Pleasant).  See a live birds of prey presentation, dissect an owl pellet, handle real and replica bird specimens, make bird crafts, and much more.  This event runs from 1PM to 4PM and is appropriate for all ages.  Free and open to the public.

May 4th          Join me at Millpond Park (607 S. Adams, Mt. Pleasant) for a nature walk as part of the Chippewa River District Library and Broadway Playhouse Kids event "Hi Ho, Hi Ho to the Park with Snow White We Go" event to promote the Broadway Playhouse Kids production of Snow White.
This Event has been cancelled due to scheduling conflicts.
May 14th         Learn about Aquatic Macroinvertebrates at the Veterans Memorial Library (301 S. University, Mt. Pleasant).  Join me at the Chippewa Valley Audubon’s regular monthly meeting as I give a presentation about insects, clams, and other underwater residents.  This event runs from 7PM to 9PM and is free and open to the public.

June 21st         Experience the nocturnal world of Moths and Owls.  Join me and expert birder Stan Lilley at Mission Creek Park (1458 N. Harris, Mt. Pleasant) at 9PM for this Chippewa Valley Audubon Club outing as we set up lights and sheets to attract moths and call for owls while we wait.  Free and open to the public.

June 26th        Aquatic Invertebrate Sampling at Hall’s Lake.  Join me and members of the Chippewa Watershed Conservancy at 9:30AM at Hall’s Lake in western Isabella County to search woodland ponds and streams for underwater life.  This program is for all ages and is free and open to the public.

Wednesday, February 12, 2014

2014 Isabella Conservation District Spring Tree Order

The deadline for ordering trees from the Isabella Conservation District 2014 Spring Tree Order has officially passed.  

Pickup of orders is scheduled for Sunday May 4th (8:00AM to 5:00PM) at the Isabella County Fairgrounds at 500 N Mission Road, Mt. Pleasant.

There may be limited quantities of extra trees available for purchase at pickup.  If you are interested in purchasing any of these extra trees, I recommend you show up early on the day of pickup as some species are gone quickly.

Look back later in the year for our Fall Tree Order (conifers only).

Program Reminder - 12 FEB 2014

Tonight (12 FEB 2014) the Chippewa Valley Audubon Club will be holding its regular monthly meeting at 7:30PM at the Veterans Memorial Library in Mt Pleasant.

Our speaker this month is Professor Daniel Patterson of Central Michigan University.   Dr. Patterson will be discussing journals from John James Audubon's 1943 journey in the American West.  From the CVAC website:

      "The discovery of three original journals from Audubon’s 1843 expedition to the confluence of
        the Yellowstone and Missouri Rivers leads us to a new and more accurate understanding of 
        what the namesake of the Audubon Society actually thought about how humans should relate
        to wildlife.  Throughout his career, his gunning ethic was a messy work in progress, but by the
        time he was done (1851), he was one of the first to advocate for the ethical consideration of
        birds and human restraint in the environment.  Daniel Patterson discusses."

This event is free and open to the public.

Tuesday, February 11, 2014

Can I eat that?

Some students in a 4th grade classroom asked a very good question yesterday.  They have been reading the book Hatchet by Gary Paulsen.  In the book, the main character Brian observes birds eating some berries and decides that they are safe to eat based on that observation.  They wanted to know if you see a bird eating berries, does that mean that those berries are safe for you to eat?

Cedar Waxwings eating the fruit from Eurpoean Buckthorn and Riverbank Grape

Fruits and berries can be placed into three categories. Some of them are edible (can be eaten) for people, some of them are inedible (may taste bad or cause sickness), and some are toxic (highly poisonous).  Birds commonly eat fruits from all three of these categories.  A bird eating a fruit or berry does not mean that it is safe for you to eat.

Let me repeat that:  A bird eating a fruit or berry does NOT mean that it is safe for you to eat!

Would you eat this berry if you found it in the woods?

Monday, February 10, 2014

Watch the Winter Olympics!

A break away from the usual science and nature blogging to remind everyone that the XXII Olympic Winter Games are currently taking place in Sochi, Russia.

I love the Winter Olympics.  I was too young to remember the 1980 Lake Placid Games, but since the 1984 Sarajevo Games I have eagerly awaited the arrival of each Winter Olympics.

The Winter Olympics feature few sports that are familiar to most Americans.  Most of the sports are never shown on the major American broadcast networks with the exceptions of ice hockey, alpine skiing, figure skating, and snowboarding.

But, once very four years we are reminded of other winter sports such as bobsled, luge, cross country skiing, ski jumping, skeleton, etc.

My favorite moment of the Olympics so far this year was watching 40 year old Ole Einar Bjørndalen win a Gold medal in the 12.5km Pursuit (Biathlon).  This marks Bjørndalen's 7th Olympic Gold medal (and 12th medal overall) in the biathlon.  He has competed in every Winter Olympics since the 1994 Games in Lillehammer, Norway. In 2002, at Salt Lake City, Bjørndalen won four Gold medals. Since then he has been on of my favorite Olympians.

For those that don't know, biathlon combines cross country skiing and target shooting with a small bore (.22 Long Rifle) rifle.  Imagine skiing as fast as you can then coming to a complete stop to shoot at a target 50 meters away that is no more than 4.5 inches wide from the standing position or 1.8 inches wide from the prone position.  Then go immediately back to skiing at full effort.  To make it worse, if you miss a target you have to complete a lap around a penalty loop - one loop for each shot you miss.

Another exciting moment (to me at least) was watching long track speed skaters form the Netherlands go 1-2-3 in the Men's 5000m.  I also got a thrill from watching the greatest Olympic wrestler of all time Aleksandr Karelin carry the Olympic torch during the opening ceremonies.

I eagerly anticipate the rest of these Olympic Games.  I hope everyone will tune in to watch the games and support the athletes from every country as they pursue their Olympic Dreams.  Unlike professional athletes in basketball, football, and baseball, most of the athletes in these sports will never become rich.  Many of them work other jobs during the year to support their participation in the sport.  They compete for the love of their sport.  Passion like this is something to aspire to.  In other countries besides the United States, Olympic competitors and especially Olympic champions are celebrated as national heroes.  Unfortunately, this is something we do not do very well in the United States - once the games are over these athletes go back into the shadows where they continue to work to improve so they can represent their country int he sport they love.  These men and women should be revered for their athletic prowess and devotion to something that they love. 

Watch the Olympics!  Be a fan and supporter of all Olympic athletes.

Friday, February 7, 2014

Standing in the middle of the river...

I have been looking back at my photos from past years to find something interesting to share and I came across a set of images from 02 February 2009.  I remember taking these photographs because of the unique circumstances.  A few days earlier, on January 27th, I had visited the Chippewa Watershed Conservancy's Sylvan Solace preserve

I remember the temperature on January 27th was very cold for Mid-Michigan.  Looking at weather records for that date show a low temperature of about -5 degrees Fahrenheit at 9:00AM.  I snow-shoed from the parking area along the River Loop.  Even with the cold air temperatures, the river was flowing freely with only a little ice along the edges.  Because the river was warmer than the air temperature, vapor was rising up and condensing in the air over the river.  Some of it was forming hoarfrost on trees along the river.  A mostly sunny sky made for some nice pictures.

I took several pictures and an idea formed in my head.

Thursday, February 6, 2014

Knowing Nature

Pop Quiz time!

Take out a piece of paper.

I want you to write the names of 100 species of plants or animals.  One rule:  every plant or animal must be native to the region in which you live.

This means no pets, farm animals, or zoo animals are allowed. 

The plants have to be native plants too.  This means no houseplants, no garden plants, no agricultural crops.

Be specific... What species of oak tree, bat, deer, mouse, etc.?

Can you name 100 species?

Here in Michigan, there are a vast number of species to choose from. 

The Field Manual of Michigan Flora lists over 2,700 species of plants.

The Michigan Audubon Society lists over 350 species of birds on its state checklist.

There are currently 66 species of mammals found in the Michigan.

Fifty-two species of reptiles and amphibians can be found in the state.

The Michigan DNR also lists 153 species of fish.

The insect species in the state number in the thousands.

It seems like it should be easy to name 100 native species, but a majority of people probably can't.  Try it and see.  Let me know if you can name 100 species for your area.

Wednesday, February 5, 2014

Next stop, the Subnivean Zone!

Last week I wrote a post about the winter habits of the Eastern Cottontail Rabbit.  In this post I mentioned that some smaller mammals make use of a space called the subnivean zone.  The word subnivean comes from the Latin root words sub "under" and nives "snow" - so subnivean translates to "under the snow".

The subnivean zone is mostly hidden from humans.  We might look at a snow covered field and see this.

A snowy field with evidence of rabbits.

Rabbit tracks, feeding evidence, and scat only show part of the story about what is going on in the field.  The snow in this picture is more than 12 inches deep.  The rabbit that left its tracks was only interacting with the surface.  More of the story is buried under the snow.

Try this some time.  Wait a few days after a snowstorm and then go find a grassy field that is covered with more than six inches of snow.  Look for an area with no visible signs of animals.  Take a flat shovel and scrape off the top inch or two of snow from a path six feet long (make sure you don't step in the path of your shovel).  You may not find anything unusual at this level.  Continue scraping off layers of snow from this path.  At some point the path you shovel will probably intersect a horizontal tunnel through the snow.  This tunnel will probably be about 1 - 1.5 inches across. 

Found it - a tunnel in the snow
Once you find one of these tunnels, gently use your shovel to follow the tunnel.  Scrape snow from the surface along the direction of the tunnel to expose it to the surface.  Be careful not to fill in the tunnel with the snow you are removing.  This tunnel will likely travel for many feet in one direction.

The subnivean world - tunnels within the snow.
Sometime those tunnels will intersect with perpendicular tunnels.  In other places the tunnels will go vertical with a shaft rising to the surface or diving downward to the ground.

The subnivean world - cross-tunnels and vertical shafts.
Find one of the spots where the tunnel drops vertically to the ground.  Dig downward at this point until you come to the bare ground.  Look closely at the sides of the hole that you just dug.  The snow is probably not the same density from the top to the bottom.  The upper few inches are probably fluffy and not compacted.  At the level where you found the horizontal tunnels, you will probably find that the snow has formed a hard crust.  This crust usually forms the floor of the tunnels.  Below this crust, the snow will often be densely compacted.  In areas without vegetation, this layer of compacted snow may go down all the way to the upper surface of the soil.  In areas a dense covering of plants, the vegetation will suspend the snow up above the level of the soil.  A lens of ice will form at this level, supporting the layers of snow above - creating a space between the snow and the surface of the soil.  This space is the true subnivean zone.  This subnivean zone will not be free of ice and snow.  Hoarfrost often develops here as water vapor rising from the soil hits the ice lens where it freezes.

A hole dug through 12+ inches of snow to reach the subnivean zone.

Here is the same image with the lines to show the crust and ice lens.

The subnivean world - snow crust (blue line) and ice lens (red line)
So what animals are creating these tunnels and using the subnivean world?  In Mid-Michigan, the most likely suspects are several species of mice and voles (kind of like a chubby mouse with a short tail).  Other animals will use the tunnels to hunt including shrews and sometimes weasels.  Even with this intrusion by predators, the subnivean world provides  freedom of movement and safety to the rodents that utilize it.  Mice and voles can move about this zone without being seen from above - they can still be heard and sometimes you will find where a fox or owl has intruded feet first into the subnivean zone to snatch a meal. 

This zone can also substantially warmer than the world above the snow.  The snow and ice eliminates the effects of windchill to the inhabitants of the subnivean zone - allowing them to retain more heat than they would if they were  inches trapped above the snow.  Snow is a great insulator and the layers of ice within the snow prevent heat from the earth from rising upward, creating a pocket of warmer air trapped just above the soil's surface.  When I was taking these pictures I sunk my shovel down into the soil with no resistance - the ground in this field has not frozen.  In areas where the snow cover is thinner (or nonexistant) the two months of cold temperatures have caused the ground to freeze to a depth of 6 inches or more. 

So next time you go outside and think that those barren snow-covered fields are devoid of life you will know that there is a whole world going on within and under the snow.

The subnivean world - tunnels criss-crossing within the snow.

Welcome to the Sunbivean Zone...

Tuesday, February 4, 2014

Two boulders, both alike in dignity...

Last month I wrote several posts about geologic concepts (cross-bedding, original horizontality, and superposition).  Every photo that I shared in those three posts was of sedimentary rocks (sandstones and shales).  This focus on sedimentary rocks was not intentional - I did not intend to ignore the fans of igneous rocks and metamorphic rocks.  In order to make up for this oversight, and to restore peace in the geologic community, I would like to share an image of a igneous rock and one of a metamorphic rock.  Both of these photos were taken over this past summer during my vacation to Maine.

The first rock is a granite boulder with a very coarse texture.  The size of the crystals in this boulder indicate that the magma that formed this rock cooled very slowly, deep below the surface of the earth, allowing large crystals to form.  Three minerals can be easily seen in this boulder:  black crystals of Biotite Mica, smoky gray Quartz, and large tan Feldspar crystals.

A coarse granite boulder

The second rock is a boulder with metamorphic origins.  Metamorphic rocks are rocks that have been changed from one rock type to another by intense heat and pressure (or through chemical interactions).  This boulder is composed of a type of rock known as Ellsworth Schist.  The dark grayish-green rock is called Chlorite.  The pale layers between the the Chlorite are bands of Quartz or Feldspar.  The layering within the rock is called foliation.  Foliations form when the the pressures that cause the rock to metamorphose are unevenly applied.  The folding within the foliations show that this rock was subjected to further pressures perpendicular to the plane of the foliations.

Details of a Ellsworth Schist boulder

Monday, February 3, 2014

I predict...

Yesterday was Groundhog Day.  Groundhogs are in short supply in Mid-Michigan during the middle of Winter, but I went outside and saw my shadow.  Therefore, I predict that winter will end in six weeks,  exactly when it is supposed to, on the Vernal Equinox (March 20th).

This Groundhog saw its shadow back in June 2013.