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.

Avian Refugees: Brown Creepers

Wet and mild winters make Northwest Louisiana a haven for wildlife. Walter B. Jacobs Memorial Nature Park is alive with bird species that have migrated here from parts north.

Brown Creepers are among those refugees.

. They can be found throughout the park.
. Listen for a very high-pitched “See…see.”
. Watch for movement from the base of a tree spiraling up, and then sinking through the air toward the base of another tree.
. They cling to tree trunks and glean small insects and spiders from grooves in the bark.
. They don’t usually eat at the feeders, but can often be seen on the trees around them.
. They have cousins who live in the Great Lakes, New England, and Pacific States all year long, but they spend their summers in Canada and their winters here with us.
. They usually leave Shreveport around the middle of March, but once one was recorded on April 15th.

If you spot a few of them in a group, you can impress your friends with this fun fact: A group of creepers is called a "sleeze," or a "spiral."

Dark-eyed Junco

Every winter an older gentleman from the Spring Lake area phones the nature park to ask about “these birds at [his] feeder.” And every year we deduce that they are Dark-eyed Juncos. He knows the juncos are the same kind of birds he sees every year, but he just can’t seem to remember that name “junco.”

It is an odd name. Some people think it’s an ugly name because it sounds like “junk” and these adorable little sparrows are not “trash birds.” I don’t understand the name, really – even when I know what it means in Latin – but I can offer you this memory tool: “Are they ‘junk?’ No!” (Get it? “Junk No/Junco.” I know, I know. Awful.)

While you try to wash that terrible pneumonic out of your brain, consider how to identify a Dark-eyed Junco:

There’s a bird in your yard (or more probably, a few of them)…
It spends a lot of time on the GROUND around the bird feeder instead of on the feeder.
It’s a bit round.
Its tail is longer than a wren’s tail is.
Its tail is not cocked up like a wren’s tail is.
It has a lot of solid gray or charcoal around the face and head.
Its belly is white, or whitish.
It has white strips along the edges of its tail that you see when it flies.
Its bill is pink.
Its whole eye looks black.
Okay, right here is where things get a little muddled. All of the statements above describe a Dark-eyed Junco, and if you can identify a Dark-eyed Junco you are doing as well as any birder needs to, but there is more…

Dark-eyed Juncos are all over the continent and all over the continent they interact with and interbreed with Dark-eyed Juncos of five separate races. At one time in the history of bird watching, these races were considered separate species. Now – because they so readily interbreed – they are lumped together as one.

Look carefully at the Slate-colored, Red-backed, Pink-sided, Oregon, and Gray-headed Dark-eyed Junco images to see if you can discern the differences. (Photos are in that order).

A flock of Dark-eyed Juncos at your feeder – of any and all races – is a delight. Just imagine! They could have flown all the way from Inuvik!

Check out the Shreveport Bird Study Group's Chart of Seasonal Occurrences to see when the juncos are usually in our area.

It's Beginning to Look a lot Like Christmas Bird Count Time

There's no better way to become a better birder than by spending time in the field with experienced birders!

Beginning on Christmas Day 1900, ornithologist Frank Chapman, an early officer in the then budding Audubon Society, proposed a new holiday tradition - a "Christmas Bird Census" - that would count birds in the holidays rather than hunt them.

So began the Christmas Bird Count.

From December 14 through January 5 tens of thousands of volunteers throughout the Americas take part in an adventure that has become a family tradition among generations. Families and students, birders and scientists, armed with binoculars, bird guides and checklists go out on an annual mission - often before dawn. For over one hundred years, the desire to both make a difference and to experience the beauty of nature has driven dedicated people to leave the comfort of a warm house during the Holiday season.

The data collected by observers over the past century allow researchers, conservation biologists, and other interested individuals to study the long-term health and status of bird populations across North America. When combined with other surveys such as the Breeding Bird Survey, it provides a picture of how the continent's bird populations have changed in time and space over the past hundred years.

If you are interested in participating in a Christmas Bird Count for the first time, visit the Shreveport Bird Study Group website or join us on Facebook. We will put you in touch with the compiler who can pair you with an experienced local birder. Or, if you happen to live within the count area, you can phone in the species and numbers you observed on the count day.

Upcoming CBCs include the Claiborne CBC, Shreveport CBC, Natchitoches CBC, and the Bossier-Caddo-Bienville CBC (the BCBCBC).

For more information on what a CBC is, visit http://www.audubon.org/bird/cbc/index.html

The Weed of Cortez

Caddo Parish parks are crawling with people – and I mean ALL of Caddo Parish’s parks are crawling with people! Noah Tyson Park in Rodessa is so far from the urban center that most people haven’t even heard of Rodessa, let alone Noah Tyson Park. Robert Nance Park in Hosston is usually the same way – usually.

But twice a year the parks get a boost from the treasure hunters. The Holiday in Dixie treasure in the spring, and the Holiday Booty in, well, you know how that goes “Christmas starts earlier every year…” The clues always seem to suggest one of our parks is the treasure site: The treasure is always hidden on public property; it’s always NOT on a busy highway; it’s often away from the hustle and bustle; there are children playing and a proximity to a body of water.

This year there are old coots and the Weed of Cortez.

“Not far off
The weed of Cortez
Knowing where to find it
Would be for the best.”

At first, we scoured the native plant databases and field guides and vascular flora books looking for a native plant named after, for, or by someone named Cortez. Then we realized something: The people who wrote those clues aren’t botanists or horticulturists. They probably have no science background whatsoever, and they are hinting at something more mundane…

So who was Cortez and what is his weed? This naturalist thinks the clue writers were referencing the Spanish explorer Hernando Cortez, and “Cortez = Spanish” and “Weed = Moss.” My apologies in advance to everyone who knows better and wants to tell me that Cortez had nothing to do with Spanish moss and Spanish moss isn’t even moss, it’s a bromeliad, hardly a weed.

And where does Spanish moss grow? On cypress trees in the bayous and lakes of South Eastern/Gulf States, of course!

Well, it doesn't grow anywhere in Walter B. Jacobs Memorial Nature Park that I know of, but I know you can find it at Noah Tyson Park, Robert L. Nance Park, and Earl G. Williamson Park. You might also check out Horace M. Downs Park, Milton "Hookie" Cameron Memorial Park, the Historic Caddo Lake Drawbridge, and Norris Ferry Boat Launch. Check out http://www.caddoparks.com/ for more information, or call the parks office 318-929-2806 for driving directions.

Happy Hunting!

WBJ Park this Late October

As of yesterday, we've received 13.93 inches of rain. We anticipate breaking the monthly rainfall record of 14.00 inches when we check the gauge tomorrow.

Ozark Trail is almost completely submerged. Ouachita Trail sports a dead fish here and there. As it nears the Ozark junction, it, too, goes underwater. Miracle Trail is washed out from the irises to Fordney Bayou. Caddo Trail is under water from Fordney Bayou to Shettleworth Bayou on both the north and south ends of the park. Adai goes under just north of the Yatasi intersection.

Even the paved Audubon Trail shows signs of recent high water, its south bend coated with mud.

This is the "occasional flooding" of a forested wetland. The palmettos and cane are thriving. The frogs and toads are booming. Dragonflies race to keep up with the plague of mosquitoes.

The Louisiana State Fair is in town, and not surprisingly, many folks would rather be down at the fair grounds than here sloshing through the water, ducking spider webs, and fending off ticks and mosquitoes. But, from the picture windows of the Interpretive Building, the fall colors are vivid: Chartreuse leaves frame fuchsia berries; turmeric, terra cotta, rust, and sulphur highlight the forest green, chocolate, and slate palette of evergreens. It seems unfair to have this view all to myself.

Craft Solution

Problem: We’re going to the National Hunting and Fishing Day Wildlife and Forestry Festival to set up a booth. About 500 festival-goers will swim past. What can we bring that will draw them in, that will distinguish us from the other exhibitors, that will send them home thinking “I’m gonna have to check out that Walter B. Jacobs Nature Park?”

The objects we bring overlap with the fur trappers’ exhibit. The animals we bring overlap with the falconers’ exhibit as well as the Department of Wildlife and Fisheries’ booth with the baby alligators.

Pamphlets and fliers end up lost on the grounds of the recreation area more often than they make it all the way back to the cars.

Solution: Crafts! And more precisely, crafts that directly relate to our traveling exhibits. We have that old alligator on a stick! If we label the craft with the park’s contact information, it might just make it all the way home.

To complement the live owl, I came up with an Owl Mask. It met all the criteria in my wanted ad for a craft: It would be a memento of meeting the live owl; it would illustrate the relative size of owl eyes to human eyes; it would have the park’s contact information on the back; it would be pre-cut and ready to decorate in the interest of saving time; and it could be decorated any way the maker wanted, using markers, crayons, glitter, etc. (Okay, the glitter part wasn’t optional. We painted every eyeball with gold glitter paint.)

The mask was a raving success! All over the festival there were children wearing owl masks.

“Where did you get that mask?”

“At the Walter B. Jacobs Nature Park booth over there!”