Saturday, December 31, 2011

The Secret Shreveport

I am cheating. I just published this on Examiner.com.

The secret Shreveport A secret path through a hidden forest along a forgotten river exists in the eye of Shreveport. Surrounded by Youree Drive, Shreveport-Barksdale Highway, Clyde Fant Parkway, and Stoner Avenue, the Coates Bluff Trail is the calm center of an urban storm. The Coates Bluff Trail can be accessed by one of three sites (assuming you need to park a car): Viking Drive at Valencia Recreation Center, East Merrick Street across from Hopewell Baptist Church, and Sykes Street next to The Montessori School for Shreveport. The trail, sometimes called Coates Bluff Greenway, Coates Bluff Nature Trail, and Coates Bluff History and Nature Trail, is on city property and is maintained by the nonprofit organization A Better Shreveport. The Coates Bluff Trail is a spectacular place to bird watch, bicycle, and hike, but the intrigue of this buried treasure is that it might actually have buried treasure! This forested land, bluff, and bayou fragment along the city’s sewer line greeted the Freeman and Custis Expedition, Henry Miller Shreve, and Jefferson Davis as they traveled north via the Red River. All of Shreveport’s early settlers – as well as untold indigenous peoples here before them – touched this little piece of land. I know of one cemetery clutching the edge of the slope behind Stoner Hill Elementary School... and of one Oldsmobile from the early 1980s enveloped in cottonwoods behind Caddo Magnet High School. What other secrets does the Coates Bluff Trail keep?

Tuesday, October 18, 2011

Behavioral Adaptation

In the parking lot of McDonald’s in Alamogordo, New Mexico, I observe a Great-tailed Grackle.

The bird approaches the side of a sedan, peers up at the fender, and walks along the edge until it spots the bumper. It hops up, views the trunk, and then flies over the car to land on the front bumper. The grackle pokes its head into the grill and emerges with an insect. It cocks its head to the side, pokes its beak into the grill again, and again emerges with an insect.

In a semi-arid desert in the middle of a drought, I had thought birds would be struggling to find enough food and moisture, but this spry grackle has made an invaluable discovery! Parked cars have grills coated with insect remains.

Friday, October 14, 2011

Goodbye Grandpappy Pine


In the beginning, there are pine trees.

Pine trees are pioneer species that populate a disturbed (deforested) area. They thrive in full sunlight. As they ascend into the clouds, they form the forest’s canopy. Maples, ashes, and oaks sprout in the shadows of the pines. May apples, blueberries, and beautyberries fill in below the understory trees. Partridge berries, violets, and various vines spread across the forest floor.

But, in this vibrant, diverse community, there is no future for the pines. Unable to tolerate their own shade, their stillborn seeds lie on blankets of their shed branches and leaves. Birds and squirrels are nourished by the seeds; worms, beetles, millipedes, and cockroaches dine on the debris.

The day will come when the pine trees die. Their carcasses may stand for years, feeding and sheltering bees, bats, and birds. Once their bodies collapse from age or disease or wind abuse, they will serve amphibians and reptiles with warmth as a multitude of decomposers pulverize them.

Unless catastrophe rips a hole in the roof, the pine trees will fade into history.

That is the way it is.

Our beloved Grandpappy Pine is dying. We could lament the loss of the biggest, oldest tree in the nature park, or we could rejoice in the success of reforestation. Either way, the time for change has come, and we must say goodbye to the 119-year-old Shortleaf Pine tree.

The tree still stands, but to prevent damage to human life and property, we may have to control the way in which it falls. Come see (touch, hug) Grandpappy Pine while you still can.

Saturday, September 17, 2011

How to Tell Cloudywings Apart

Southern Cloudywings eat powdered pastries from Southern Maid Donuts.

Their faces are white.
Their wing spots are bright.
They even have some sugar on their antennae.

Northern Cloudywings are gloomy from dirty old snow.

Their faces are gray.
Their wing spots are faint.
Their antennae are dark, too.

Confused Cloudywings are just that. Sometimes they have a little powdered sugar, sometimes some dirty snow.

Friday, September 2, 2011

A Sad Reality about Science Education

I attended Back to School Night at my children’s school. I went into the science classroom eager to meet the teacher and to discover how she would be inspiring her students to love science and nature.

I departed in sorrow. The science teacher is also the social studies teacher. She happens to know there is very little science on the standardized test for this grade level, so she won’t be focusing too much on it.

If this is the sentiment of educators in a magnet school whose students were accepted for admission based on their above-average aptitudes, how could I hope it is any better in general population schools?

I knew there was much grumbling about ‘teaching to the test,’ but I could not have imagined that educators would forsake their higher mission. I have never met a person who said “I wanted to be a teacher so I can encourage learners to learn only what they must to get by.”

The pragmatist in me wants to scrutinize the curricula of social studies, and other subjects, to find areas where science overlaps in order to argue the importance of teaching science. I want to find the research articles that demonstrate that students with a solid science education score higher on those tests in other subject areas as well. I need to prove that programming at the nature park is worthwhile. I need to demonstrate why I – the natural science interpreter – am relevant to society. But, I can’t help but feel sad that I must show these things to – of all people – professional educators.

I wish the schools had the courage to put those standardized tests in their place and get back to the business of exposing young minds to existing knowledge and encouraging them to explore and make new discoveries.

Wednesday, August 31, 2011

The Scientific Method in the context of Nature

The words “science” and “nature” are often used together, yet they are often thought of as very different concepts. Science is a laboratory with beakers, test tubes, and microscopes, while Nature is a museum of plants, animals, and rocks. However, everything we know about our natural world has been learned through scientific investigation.

The first step in the scientific method is to identify a "problem."

The leaves of several deciduous trees dried up and turned brown and are either falling to the ground or hanging on the branches. Why is this happening?

Then you gather information:

The leaves of deciduous trees die and fall off during the fall and winter months. Leaves also die and fall off when the entire tree dies due to age, trauma, diseases, and pests.

Next, you form a testable question (aka, a hypothesis):

If the phenomenon is caused by a disease or pest, you will be able to see a relationship among the kinds of trees affected.

In question form… Are they all the same species of tree and is every individual of that/those species in the forest brown?

Now you need to come up with a way to find the answers:

Use field guides and dichotomous keys to identify the afflicted trees.
Use field guides and dichotomous keys to identify the apparently healthy trees in the same area.

What did you find out? (This is simply the observation. We often move so quickly from making an observation to drawing an inference that we do not realize that they are two separate steps.)

30% of the brown trees are flowering dogwood. 55% of the brown trees are oak species. 10% of the brown trees are hickory species, and 5% of the brown trees are maples. Green, apparently healthy dogwoods, oaks, hickories, and maples were observed in the area.

What do you think this means? (This is the conclusion or inference that you draw based on your observations. Often, results can be interpreted multiple ways. Always, the inference inspires further investigation to which the scientific method can be applied.)

This phenomenon is occurring in several species of trees, therefore, the trees are most likely not contracting a pathogen or pest that affects whole populations of a species such as Dutch Elm Disease, or Emerald Ash Borers. A disease or pest that attacks many kinds of trees would attack all compatible trees in the area, so it is unlikely that the brown, dead leaves are the result of a disease or pest.

Hmm… [And the Scientific Process begins again]

Problem: Did the trees die? Or did they go dormant early?

Information: We know that deciduous trees appear to be dead in the winter because their leaves turn brown and usually fall off. We know that below the bark, the part of the tree that grows new cells, called the cambium, is moist and green in dormant trees, and brown and dry in dead trees.

Hypothesis: If the trees are alive, but dormant, we will observe a healthy cambium layer.

Procedure: Use a small tool such as a pocket knife or a fingernail to cut away a small section of bark to examine the cambium.

Results: 95% of the trees tested have a green, moist cambium under the bark. 5% of the trees are brown, dry, and brittle beneath the bark.

Conclusion: Most of the brown trees have stopped photosynthesizing but are still alive. They have gone dormant in response to some kind of stress. A few trees have died. The dead trees may have been unhealthy to begin with and so were unable to endure the environmental stress. Those few trees may have even been dead before the phenomenon was observed, or died of an unrelated problem.

Further inquiries: We may want to know if the early dormancy impacts other organisms in the forest, or if the openings in the canopy allow other plants to grow, or if the deciduous trees will grow again before the fall. Then we may want to know how long deciduous trees can be dormant before they become unhealthy and die. The process of scientific investigation is continual.

In short, the more we know, the more there is to know. Nature is full of questions waiting to be asked and answered using the scientific method.

Wednesday, March 16, 2011

Forest Sing Along Variation (Easier)

"Wheels on the Bus" Variation

Deep in the forest, near a spot of sun
spot of sun, spot of sun
Deep in the forest, near a spot of sun
Lived a warty mother toad and her little toadie one

Deep in the forest, where the stream runs through
stream runs through, stream runs through
Deep in the forest, where the stream runs through
Lived a shiny mother fish and her little fishes two

Deep in the forest, in a hole in a tree
hole in a tree, hole in a tree
Deep in the forest, in a hole in a tree
Lived a chatty mother wren and her little birdies three

Deep in the forest, by the bayou shore
bayou shore, bayou shore
Deep in the forest, by the bayou shore
Lived an old mother muskrat, and her little ratties four

Deep in the forest, in a snug beehive
snug beehive, snug beehive
Deep in the forest, in a snug beehive
Lived a mother honey bee and her little bees five

Deep in the forest, in a nest of sticks
nest of sticks, nest of sticks
Deep in the forest, in a nest of sticks
Lived a black mother crow and her little crows six

Deep in the forest, in the leaves soft and even
leaves soft and even, leaves soft and even
Deep in the forest, in the leaves soft and even
Lived a cheery mother cricket and her little crickets seven

Deep in the forest, by a mossy gate
mossy gate, mossy gate
Deep in the forest, by a mossy gate
Lived a brown mother lizard and her little lizards eight

Deep in the forest, where the quiet pools shine
quiet pools shine, quiet pools shine
Deep in the forest, where the quiet pools shine
Lived a green mother frog and her little froggies nine

Deep in the forest, in a sly little den
sly little den, sly little den
Deep in the forest, in a sly little den
Lived a gray mother spider and her little spiders ten

For the tune, copy and paste this link http://kids.niehs.nih.gov/lyrics/wheels.htm in a separate window so you can read the words and hear the tune at the same time.

Forest Sing Along

Deep in the forest,
Near a spot of sun
Lived an old mother toadie
And her little toadie one
"Wink!" said the mother;
"I wink!" said the one,
So they winked and they blinked
Near a spot of sun

Deep in the forest,
Where the stream runs through
Lived an old mother fish
And her little fishes two
"Swim!" said the mother;
"We swim!" said the two,
So they swam and they leaped
Where the stream runs through

Deep in the forest,
In a hole in a tree
Lived an old mother wren
And her little birdies three
"Sing!" said the mother;
"We sing!" said the three
So they sang and were glad
In a hole in the tree

Deep in the forest,
By the bayou’s shore
Lived an old mother muskrat
And her little ratties four
"Dive!" said the mother;
"We dive!" said the four
So they dived and they burrowed
By the bayou’s shore

Deep in the forest,
In a snug beehive
Lived a mother honey bee
And her little bees five
"Buzz!" said the mother;
"We buzz!" said the five
So they buzzed and they hummed
In the snug beehive

Deep in the forest,
In a nest built of sticks
Lived a black mother crow
And her little crows six
"Caw!" said the mother;
"We caw!" said the six
So they cawed and they called
In their nest built of sticks

Deep in the forest,
In the leaves soft and even
Lived a cheery mother cricket
And her little crickets seven
"Chirp!" said the mother;
"We chirp!" said the seven
So they chirped cheery notes
In the leaves soft and even

Deep in the forest,
By the old mossy gate
Lived a brown mother lizard
And her little lizards eight
"Bask!" said the mother;
"We bask!" said the eight
So they basked in the sun
On the old mossy gate

Deep in the forest,
Where the quiet pools shine
Lived a green mother frog
And her little froggies nine
"Hop!" said the mother;
"We hop!" said the nine
So they hopped and they splashed
Where the quiet pools shine

Deep in the forest,
In a sly little den
Lived a gray mother spider
And her little spiders ten
"Spin!" said the mother;
"We spin!" said the ten
So they spun lacy webs
In their sly little den


Find the tune here: http://kids.niehs.nih.gov/lyrics/overmeadow.htm

Monday, January 24, 2011

Dead but Not Gone

Ever wonder why at this time of year a lot of deciduous trees look like this:
Instead of this:

How come the leaves died but didn’t fall off the tree? Do we need more wind?

There’s actually a word for it. It’s called marcescence. (I know. I just had to assure my spellchecker that it’s a real word.) Even though the word doesn’t exactly roll off the tongue, the phenomenon is interesting.

Normally, when deciduous trees sense that it’s time to close up shop for the season, they drain all the leaves of fluids (like water and chlorophyll), and form a scab where the stem of each leaf meets the branch. When the scab is complete, there is nothing holding the old leaf to the tree, and the slightest breeze blows it away.

The bare tree stands ready to tough out freezing temperatures and heavy precipitation (and I mean heavy in weight as well as volume).

But marcescent trees don’t finish that last part of the scab until winter is over, so the trees stand holding their dead leaves for three whole months. Why?

It’s a mystery.

It seems like holding all your leaves would be a liability if you were a tree in a climate prone to heavy snows and/or frequent ice storms, because the leaves would hold the precipitation and weigh down your branches until they broke off.

Marcescence occurs more frequently with young trees than old ones, and it is typical of only some species. Though no one is sure exactly why it occurs, there are a few interesting ideas…

The bare winter tree may look like a pile of sticks to us, but to an animal that just had to shift its diet from juicy green leaves to nuts, berries, and TWIGS, it looks like something else entirely. Leaf buds have formed on the branches. The buds and the branches are full of sugary sap (aka FOOD). A hungry deer may eat a small tree all the way to the ground.

But – to you, me, and the deer – a tree that holds its dead leaves looks like a dead tree, and dead trees are brittle and dry. The deer will skip over the dead-looking trees in search of juicier treats.

Another possibility is that the retained leaves act like thousands of blankets insulating the baby leaf buds from the cold. This may work out in climates where it sometimes gets cold enough to freeze water but not wet enough to weigh down branches.

Still another possibility is that the dead leaves function to keep moisture from evaporating out of the branches and buds. (Did you know that there are only two ways for water to get out of a plant? An animal takes it out, or it transpires through the leaves and stems. In essence, plants sweat.)

All of these ideas seem plausible. In fact, the marsescent tree may benefit in all of these ways.

Then again, maybe there’s still more to discover about the phenomenon. The forest is full of questions waiting to be asked.