Today's Ramble
was led by Dale Hoyt.
Here's the link to Don's Facebook album for today's Ramble.
(All the photos in this post are compliments of Don, unless otherwise credited.)
Today's post was
written by Dale Hoyt.
Today’s Focus: Seeking what we find on the Purple and
Orange Trails.
21 Ramblers met
today.
Announcements:
1.
This
weekend is the big fund-raising event for the State Botanical Garden of
Gerogia. Andrea Fischer told us that the contributions from this year’s Ball
will be earmarked for the Conservation program.
2.
Friends First Friday, is usually, as the name implies, held on
the first Friday of each month. But due to preparations for this weekend’s Gala
it has been postponed until the following Friday,
May 10. Our very own Don Hunter will be talking about the Nature Ramblers
and other activities he is involved with. Expect plenty of wonderful
photographs. Sign up soon if you plan to attend.
Today's
reading:
Dale read an excerpt from the book Crow
Planet by Lyanda Lynn Haupt; Little, Brown & Co., 2009, pp. 4-5:
Many nature writers
send dispatches from their wooded homes with the brook babbling outside the
ever-open window; they go on weeks- or months-long solitary rambles in remote
places. They bring us along, in their writing, on these adventures and in the
musings they inspire. And they do inspire. Certainly, I believe that
wilderness experiences are both restorative and essential on many levels. . . .
But in making such experiences the core of our "connection to nature"
we set up a chasm between our daily lives ("non-nature") and wilder
places ("true nature"), even though it is in our everyday lives, in
our everyday homes, that we eat, consume energy, run the faucet, compost,
flush, learn, and live. It is here, in our lives, that we must
come to know our essential connection to the wilder earth, because it is here,
in the activity of our daily lives, that we most surely affect this earth, for
good or for ill.
Today's Route:
From the plaza across
the Flower Bridge and through the formal gardens to the head of the Purple
Trail, which we to the Orange Trail and then walked downstream on the Orange
Trail, following it around the beaver marsh up to the upper parking lot.
LIST OF
OBSERVATIONS:
Visitor
Center Plaza Fountain:
 | |
| Pitcher plant flowers; the expanded end of the pistil is well displayed by the flower on the left. You can see three of the five stigmas. |
Pitcher
plants: There are
several species of pitcher plants growing in the plaza fountain pool, some of
which are in flower. The flowers face downward and in the center of each flower
there is a structure that looks like an upside down opened umbrella. This is
the expanded end of the pistil, the female part of the flower. The umbrella
collects pollen that falls from the stamens above it and the edges of the
umbrella bear the stigmas that receive pollen. Large, hairy bees enter the
flower between the petals, bumble around on the umbrella, picking up pollen
that they will transfer to the stigma of another flower when they visit it.
The pitcher
of the pitcher plant is highly modified leaf. It is a tube open at the top and
the top edge usually is coated with a slippery wax. Below the waxy portion
there are numerous downward-pointing hairs. Insects are attracted to the
opening and slip on the wax, falling down into the fluid that collects in the
pitcher. The hairs make it difficult for them to crawl out and eventually they
die and decompose in the pitcher fluid.
Each pitcher
is a tiny ecosystem consisting of dead and decomposing insects and the bacteria
that do the decomposing. In addition there are mosquitoes the live nowhere else
except the pitcher plant. Their larvae consume the bacteria that feed on the
dead insects, and the mosquito poop adds nitrogenous compounds that is absorbed
by the pitcher. And the pitcher plant needs that nitrogen because it is growing
in a sterile bog that is especially short of nitrogenous fertilizer.
Azolla
ferns:
 | |
| Azolla ferns floating in a ring to prevent their escape. |
 | |
| Closeup of the floating Azolla ferns. |
Oakleaf
Hydrangea: At the start of the
pathway to the flower bridge is a large Oakleaf Hydrangea that is beginning to
bloom.
Each inflorescence consists of two kinds of flowers, large, showy flowers
that have pretty white petals but lack sexual organs (the stamens and pistils).
These flowers are sterile.
The other kind of flower is very inconspicuous and
lack petals but has the sex organs. The showy sterile flowers are there to
attract the attention of pollinators who will spend time foraging for pollen
and nectar produced by the smaller flowers. Of course the plant breeders have
“improved” this plant by producing varieties that have more of the showy,
sterile blossoms. This reduces the number of flowers that produce pollen and
nectar. Some varieties even have no functional flowers.
 | |
| Oakleaf Hydrangea; several inflorescences with sterile white blossoms are visible. |
 |
| The tiny, fertile flowers of Oakleaf Hydrangea. |
How wood decays: On our way down the Purple Trail we encountered a broken
tree stump in advanced stages of decay. The lions share of recycling the
nutrients in trees falls to fungi. Trees are made of durable materials; that’s
why we build our homes with them. Like all plants the cells of trees are enclosed
in a cell wall made principally of cellulose. You can think of a plant cell as a
very tiny, damp cardboard box. A tree is made from trillions of the little
boxes, stacked on top of the other. But you can’t stack wet cardboard boxes
very high without them collapsing. If cellulose were the only material found in
plant cells there wouldn’t be any forests – all plants would be very short.
In addition to the cellulose there is a stiffening agent in
the cell wall, a substance called “lignin.” Together, the cellulose and lignin
enable trees to grow to extraordinary heights without collapsing from their own
weight.
These molecules aren’t simple; they cost a plant a lot of
energy to make. Cellulose is basically a lot of sugar molecules chemically
hooked together to form long chains. That sugar came from photosynthesis, so a tree
makes its own backbone. Lignin is a much more complex substance and more
expensive to make. That’s why some plants prefer to not be trees. They can’t
afford to make the amount of lignin needed to become tree-like.
Some fungi, in their search for food, have learned to
digest cellulose and/or lignin and have specialized on feeding on dead trees.
These are known to us as the various kinds of “rots.” Two of the commonest are the
white rots and the brown rots, named for the color of the wood they leave when
they have finished eating their meal.
Cellulose is white in color, lignin brown. If a fungus
digests the cellulose the wood that remains is brown from the remaining lignin,
thus it is a “brown rot.” Similarly, if a fungus feeds on the lignin in the wood,
it leaves behind the light-colored cellulose – it’s a “white rot.” In effect
they are named for what they don’t eat.
(An aside: The paper industry basically grinds up trees to
make paper. If the pulp is left untreated it makes brown paper. To make white
paper the lignin must be removed and that is done by using harsh chemicals to
destroy the lignin in the wood pulp. If fungi were employed to remove the
lignin there would be far less pollution from paper mills. But so far there has
been little success in developing a treatment process using fungi to process
the pulp.)
 |
| Lateral view of the stump; the outer part of the stump is brown, indicating that cellulose has been removed; the inner core is very light in color, indicating that the lignin has been removed. |
 |
| Top view of the stump; central part with lignin removerd; outer layers with cellulose removed. |
But back to the stump. It shows evidence of having been
colonized by cellulose eating fungi on the outer layers of wood and lignin
digesting fungi on the interior. In the very center you can see a cylinder of very
light colored wood from which most of the lignin has been removed. This was
probably surrounded by a layer of lignin-impregnated cells that have completely
rotted away.
Orange Trail:
 |
| Outer portion of trunk blown off by lightning. |
The dramatic rains
a week and a half ago were accompanied by thunder storms. Emily spotted the
aftermath of those storms: a fresh lightning strike on a tall tree near the
beaver marsh. When lightning strikes a tree the bolt travels down toward the
ground. The path it traces experiences enormous, rapid heating and this
instantly vaporizes the sap inside the trail the bolt of energy traces down the
trunk. The overlying wood and bark are violently ruptured and blown away by the
steam explosion, leaving a scar that will remain with the tree for the rest of
its life.
 |
| Beaver Meadow with brown mud line from recent flood. |
All the vegetation in the area affected by the flood was covered with brown
silt and this presented us with a fortuitous opportunity to see how rapidly
vegetation grows. Examine a branch that had been totally submerged. Some of
these branches will have green leaves without a silt covering at the very end.
This is new growth that occurred in the 10-11 days after the flood water
receded.
Frogs and Toads
Many people are confused about the
difference between frogs and toads and rightly so. Amphibians consist of three different
groups of animals: Anura (Frogs), Caudata (Salamanders) and a third group no
one, except herpetologists, has heard of: caecilians. Adult salamanders have
tails, adult frogs lack tails and their hind legs are modified for jumping. “Toad”
has no exact meaning. It is commonly used to refer to a warty frog that spends
a lot of time away from permanent bodies of water. Almost all frogs, and this
includes what most people would call toads, in North America must return to
water to mate and lay their eggs. Frogs like Bullfrogs and Leopard frogs are found
in association with permanent bodies of water, but many other kinds of frogs
are only found in water during the breeding season. Tree frogs (or tree toads,
take your pick) are often seen away from water. One family of Frogs, Bufonidae,
consists of what most people think of as toads: squatty things with dry, warty
skin. But even these amphibians need to have a wet environment to avoid
excessive water loss. That’s why toads usually hide in leaf litter or under
objects during the day and come out at night to forage for food.
Green Frogs: The beaver marsh
supports a large population of Green Frogs. (A Green Frog looks like a small
Bull Frog.) Yesterday (Wednesday) I visited the marsh between 11 a.m. and 1
p.m. and heard a large chorus. It was much warmer then than it was this morning
and we only heard one or two calls. The call is difficult to describe. It’s
been compared to a low-sounding banjo string. To me it sounds like a loud, swallowed
burp. (Try to swallow some air while keeping your mouth shut. The “glump” sound
approximates the call. Better yet, listen to this recording. The tadpole stage lasts from 3 to 22 months.
 | |
| American Toad, unusual in that it lacks dark spots on its back. |
American Toad: We found an
unusually colored American Toad in the mud by the Scout Bridge. Almost all American
Toads have several black spots that surround groups of warts on their backs.
This individual lacks the black spots completely. It would be difficult to notice
on a background of Georgia red clay.
 | |
| Wolf spider with egg sac attached to her spinnerets. |
Wolf spider: We captured a
female Wolf spider carrying a large, whitish egg sac attached to her abdomen. She
will carry the egg sac until the spiders inside are ready to hatch. Then she
will open the sac and the tiny spiders climb out onto her body. She will carry
them for a couple of weeks, after which they will disperse and fend for
themselves. Wolf spiders are active hunters and do not spin silken webs like
other spiders. They feed on a variety of insects and even on small, newly
metamorphosed toads that they encounter. Unlike their namesake, they are
solitary and search for food alone.
The egg sac can be parasitized by an insect called a mantisfly or
mantispid. The adult looks like a very small praying mantis. When the larval mantispid
encounters a female wolf spider it hitches a ride. When the spider makes her
egg sac the mantispid larva sneaks inside. Unbeknownst to the female the
mantispid larva begins to eat her eggs. When it has grown to the appropriate
size it pupates inside the egg sac and finally metamorphoses into an adult,
breaking its way out of the egg sac.
 | |
| Small Garter Snake; you can see the fork in the end of the tongue. |
Garter Snake: Someone spotted a young Garter Snake and I
was able to capture it. The name refers to a time when men wore colorful straps
around their calves. Attached to these straps were clips on elastic attached to
the garter straps. The clips held up the socks. The straps had decorative
stripes, just as the Garter Snake has stripes that run the length of its body.
Garters are a thing of the past and many people who as what kind of snake is
misinterpret the “garter” as “gardener,” because that makes more sense.
Many ramblers remarked on the snakes tongue
which it frequently projected from its mouth. The tongue is forked and was
flicked up and down each time it was projected. This strange (to us) behavior
is one way the snake smells its environment. The tongue is moist and when it is
projected and waved about environmental odors are absorbed on its fluid surface.
When the tongue is retracted the tips are flipped up to a pair of sensory organ
in the roof of the mouth, the vomeronasal organs. These are fine tuned to
detect pheromones produced by female snakes as well as other odors. (Humans
have a vestigial version of the vomeronasal organ called Jacobson’s organ. It
appears to be nonfunctional in humans.)
 | |
| Hole near the stream made by unkown animal, perhaps a crayfish. |
Mystery hole: We often see soil or leaf litter in the Garden
that has been disturbed. Usually the guilty person is a squirrel or an
armadillo, or at least we can convince ourselves that is the case. Today we
found a large hole with scraped dirt surrounding it. Definitely not a squirrel disturbance,
but the hole looked too large to have been made by armadillo and not large
enough for a chipmunk. I think it may have been made by a crayfish (AKA
crawdad, mudbug) and then disturbed by a possum or raccoon. I have seen crayfish
mounds in the garden before. The animal excavates a tunnel near a body of water
and uses the dirt to build a turret around the entrance. The hole we saw could
have had the turret messed up by another animal looking for a meal. This could
explain the size of the hole.
 | |
| Mayapples covered in mud by flood waters. |
Mayapple Rust:
Most of the Mayapples are infected with Mayapple Rust. In previous
weeks we have seen this fungal pathogen’s rusty orange spore cups on the under
surface of the Mayapple leaves. Now either the spores have been dispersed or
washed away by the flood waters. All that remains on the undersurface are dark
spots.
Ferns:
 | ||
| Broad Beech Fern -- resembles a Fox's face |
 | |
| Rattlesnake Fern; the fertile frond is visible agains the tree trunk; it arises from the sterile fronds below. |
SUMMARY
OF OBSERVED SPECIES:
Purple Pitcher Plant
|
Sarracenia
purpurea
|
Carolina mosquito fern
|
Azolla cristata
|
Ebony Spleenwort
|
Asplenium
playtneuron
|
Oakleaf Hydrangea
|
Hydrangea
quercifolia
|
Yellowwood Tree
|
Cladrastis
kentukea
|
Green Frog
|
Lithobates clamitans syn. Rana clamitans
|
Eastern Phoebe
|
Sayornis phoebe
|
Northern Red Oak
|
Quercus rubra
|
Eastern Tiger Swallowtail
|
Papilio glaucus
|
Sensitive Fern
|
Onoclea sensibilis
|
American Toad
|
Anaxyrus americanus syn. Bufo americanus
|
Tulip Tree
|
Liriodendron tulipifera
|
Wolf Spider
|
Family
Lycosidae
|
Carolina
Wren
|
Thryothorus ludovicianus
|
Tufted
Titmouse
|
Baeolophus bicolor
|
Red-shouldered
Hawk
|
Buteo lineatus
|
Mayapple
|
Podophyllum peltatum
|
Mayapple
Rust
|
Allodus podiphylli
|
Garter
Snake
|
Thamnophis sirtalis
|
Summer
Bluet
|
Houstonia purpurea var. pupurea
|
Jack-in-the-Pulpit
|
Arisaema triphyllum
|
Christmas
Fern
|
Polystichum acrostichoides
|
Broad Beech
Fern
|
Phegopteris hexagonoptera
|
Rattlesnake
Fern
|
Botrypus virginianus
|
Red-eyed
Vireo
|
Vireo olivaceus
|
