Today's Ramble was led by Linda Chafin.
The photos in this post, except where
noted, came from Don's Facebook album (here's the link).
Today's post was written by Linda
Chafin & Dale Hoyt.
23 Ramblers met today.
Announcements:
1) Next week (August 3) our meeting place will change to the front
courtyard at the Visitor's center front fountain. We will no longer assemble at the Arbor. This change is due to the
Children's Garden construction beginning on Aug. 1. It is likely that there
will be no parking available in the lower lot after that date. Everyone
should begin parking in the upper parking lots.
2) Gary
Crider told us about the effort of our local art cinema theater, Ciné, to
purchase the building it currently occupies:
The executive director at Ciné has temporarily reserved a
full row of 12 seats for the Nature Ramblers. So, I need only 11 more Ramblers
to commit to join me on Rambler Row. Ciné is a 501(c)3 non-profit, so
your contribution is tax deductible. And here's the kicker: an anonymous
supporter has pledged to match each $150 seat donation between now and
September 15. Our reserved row is
available for an unspecified, limited time only, so we need to act promptly.
For details on the "Buy Ciné" campaign, see http://athenscine.com/support.php
Contact Gary to join the Rambler Row. Email gcrider AT charter DOT net or call 706-714-4430
Contact Gary to join the Rambler Row. Email gcrider AT charter DOT net or call 706-714-4430
Today's reading: Dale read a
passage from John Burroughs' essay The
Art of Seeing Things.
The
book of nature is like a page written over or printed upon with different-sized
characters and in many different languages interlined and cross-lined, and with
a great variety of marginal notes and references. There is coarse print and fine print; there
are obscure signs and hieroglyphics. We
all read the large type more or less appreciatively, but only the students and
lovers of nature read the fine lines and the footnotes. It is a book which he reads best who goes
most slowly or even tarries long by the way.
He who runs may read some things.
We may take in the general features of the sky, plain, and river from
the express train, but only the pedestrian, the saunterer, with eyes in his
head and love in his heart, turns every leaf and peruses every line. One man sees only the migrating waterfowls
and the larger birds of the air; another sees the passing kinglets and hurrying
warblers as well. For my part, my
delight is to linger long over each page of this marvelous record, and to dwell
fondly upon its most obscure text.
[For those unfamiliar with John
Burroughs (1837-1921): He was the rock-star naturalist and nature essayist of
his time, a household name. In his later years he counted among his friends
such luminaries as Theodore Roosevelt, John Muir, Thomas Edison and Henry
Ford.]
Today's Route:
We left the arbor and headed down the Shade Garden path to the left of
the arbor and left the sidewalk path for the mulched path, making our way down
to the White Trail spur, which we took over to the power line ROW. On our way back, we went through the Dunson
Native Flora Garden in search of Cranefly Orchids, which we found. After the orchid search, we headed back to
the Visitor Center and the Cafe Botanica.
 |
| Barred Owl feather |
 | |
| Downy Woodpecker (?) feather |
Just before the Ramble started Berkeley Boone, the
Childrens Program Manager at the Garden and a fine naturalist, handed me a feather
from a Barred Owl. Later, on the Ramble, we found a much smaller feather that
was probably from a Downy Woodpecker.
 | |
| Cranefly Orchid flowers |
Now is the time to search for Cranefly Orchid (
 |
| Moth with orchid pollinium attached to its eye. |
As with most orchids, Tipularia
pollen is packaged in a sack called a pollinium. Each pollinium contains
thousands of pollen grains. When a noctuid moth visits the flower for nectar it
bumps into the pollinium, gluing it to the moth's eye. The pollinium will be
transferred to the next blossom the moth visits, where it gets scraped off and
the contained pollen fertilizes thousands of tiny orchid seeds.
Wild orchids are famous for taking a year or two or even
ten off, their corms or rhizomes lying dormant in the soil. You may wonder, as
do plant biologists, what is the benefit of such long dormant periods, when the
plant can’t photosynthesize. It may have to do with the fact that orchids are
mycorrhizal–their roots are attached to an underground fungus. The fungus may
also be attached to another plant that is actively photosynthesizing and
passing the sugars to the orchid’s underground storage organ via the fungus. If
this is the case, the orchid is effectively parasitizing the mycorrhizal
fungus, as well as the fungus' other partner. Though not confirmed, this
three-way relationship between the orchid, the fungus, and the aboveground
plant may provide enough nutrients for the orchid to build its strength in
preparation for the next flowering period.
After careful searching along our route we finally found Cranefly
Orchids in bloom in the Dunson Garden.
 | |
| Recently metamorphosed Eastern Spadefoot |
On the White Trail Spur one of our junior Ramblers,
Nathan, was the first to notice hundreds of tiny, newly metamorphosed frogs.
This was just the first location; more were seen in the moist leaf litter in
other places. Were they toads? Or frogs? They are Eastern Spadefoots, a species we have seen on earlier rambles.
A Rant about Frogs
and Toads
For most people a toad is a short legged, squatty
creature with dry, warty skin. When a toad moves it either walks or hops and
they are found away from water. On the other hand, frogs have a moist, slick
skin that could be described as slimy. They are found either in or near water
and use their long legs to jump or leap away.
The problem with these definitions is that they describe
such a small part of the diversity of tailless amphibians, which is how
zoologists define frogs. For example, many of us have found a tailless
amphibian clinging to a window or a door. Is it a toad or a frog? It has long
legs and can jump away like a frog, but it is not near water. Most folks create
a new category for this kind of amphibian; they call it either a tree frog or a
tree toad.
But expanding the types of frogs (in the zoological
sense) to three doesn't include the diversity of frogs in the world. Even in a
small part of the world, like Georgia, we have more than three kinds of frogs.
(Kinds roughly corresponds to zoological families.) The Amphibians and Reptiles of Georgia lists six families of frogs
in the state: True Toads, Treefrogs, Rain Frogs, Narrow-mouthed Toads,
Spadefoots and True Frogs. Of these, True Toads corresponds to what are
vernacularly called "toads," True Frogs corresponds to what most
people think of as "frogs" and Treefrogs are, unsurprisingly,
"Treefrogs." The six families of frogs found in Georgia are but a
fraction of the worldwide frog diversity. A recent publication lists a
worldwide total of 44 families. All of the 6000+ species are frogs.
End of rant.
Spadefoots are a small
family of frogs (only 7 species) found only in North America. Most spadefoot species
live in arid environments and their breeding habits are adapted to prairies and
deserts where rain is infrequent. Unlike most frogs they do not have a regular,
seasonal breeding season. They breed only during and shortly after torrential
downpours that form temporary pools of water. Some years they may not breed at
all; in others, they could breed two times. Among the North American frogs they
have the shortest developmental rate, going from egg through tadpole to
metamorphosis in as little as 30 days. They need to develop that rapidly
because the pools they breed in often don't last very long. I have seen spadefoot
tadpoles dying in muddy tire tracks that retained a little, but not enough
water.
The spadefoot name comes from a shovel-shaped projection they have on
bottom of their hind feet. This "spade" helps them to burrow into
loose soil. When you place a spadefoot on sandy soil it begins to shuffle its
hind feet. As it does so, it rapidly sinks out of site, completely burying
itself in just a few minutes. Burial is how they survive in desert
environments. During harsh times they bury themselves and enter a state like
hibernation, called aestivation, in which their metabolism decreases. In that
condition they can survive without food or water for several months. Apparently
it is the thunder of severe storms that arouses them when the storm is vigorous
enough. They emerge, rehydrate, and seek out the temporary pools where they
commence breeding.
Where did all
these tiny frogs come from?
The Botanical Garden has several wetlands: the Beaver marsh by the
Orange trail, and the areas of the flood plain inside the river levee. The
marsh is fed by the creek that runs next to the Orange Trail and is fairly
permanent, but in years of severe drought it has almost completely dried, along
with the creek. The flood plain levee areas are less permanent bodies of water.
They are dependent on the run off from the slopes to the north and in drought
years will completely dry up. They are also periodically submerged when the
Middle Oconee river overflows its banks. These are the major breeding sites for
frogs in the Garden. Treefrogs, True Frogs, True Toads and Spadefoots all breed
in the flood plain and/or marsh. On previous Rambles we have seen the egg
masses of Leopard frogs and the long strings of eggs deposited by American
toads in the temporary pool that forms in the power line right of way. All the
frogs that breed in the Garden have an aquatic larval stage, called a tadpole,
that feeds primarily on the algae, plants and bacterial scum in those temporary
pools – basically a vegetarian way of life. When they reach a certain size they
begin to change into air breathing insectivores, a process called
metamorphosis. During this process the tadpole body undergoes profound changes:
arms and legs appear, gills are lost and lungs develop, the gut becomes shorter
and adapted to more protein-rich food and the mouth, tongue and jaws change to
be able to handle live, squirming food items.
Because each female frog lays thousands of eggs thousands of tiny,
newly metamorphosed frogs will clamber onto the land bordering their natal
pools.
All these frogs will begin to forage for small insects and they are
faced with many dangers and competitors. Perhaps the largest threat they face
is dehydration. Small creatures have a large surface area in relation to their
size. With their moist skins frogs lose water by evaporation very rapidly. For
this reason they are most active by night, when the relative humidity is
higher. (Also a time when small insects are active – for the same reason –
reducing water loss.) During this activity they venture further from their
natal pools and come daylight they need to find a moist shelter that will
reduce the risk of desiccation. That could be under a log, rock or leaf litter.
If rain is frequent or heavy there will be enough microhabitats for them to
survive away from the birth pools. But the danger of dispersing in the rain is
that eventually they will have wandered far enough that they cannot escape the dry
periods in between rainfall. They perish by the thousands.
That is how the hundreds of little Eastern Spadefoots got to where we
found them – one night at a time and enough rain to keep the leaf litter
moisture laden, even between storms.
Insects:
 | |
| Velvet Ant male |
Velvet ants aren't really ants, they are solitary wasps
(family Mutillidae). They are called "ants" because the wingless
females are often seen running on the ground like a big, colorful ant. The
males have wings and are seen far less often. Strangely enough, the males are
just as colorful as the females, but they differ so much that most of them were
described as different species. Matching up the males with the right female
requires capturing a pair in the act of mating, an exceedingly rare thing to
observe.
Today we were
fortunate to find two males. I took this opportunity to demonstrate that male
wasps can't sting – they don't have a stinger. (The stinger of ants, bees and
wasps is a modified ovipositor. An ovipositor is a structure that is used to
lay eggs. Because male ants, bees and wasps aren't females they never develop
an ovipositor and, therefore can't sting.) Because the velvet ants we found
today had wings I knew they were males and I could grab one with impunity and
never get stung.
There are several
interesting things about velvet ants: they parasitize the nests of other bees
and wasps, they have the longest sting, relative to their body size, of any
wasp and they have crush-proof bodies. The females enter the nests of ground
nesting bees or wasps and deposit eggs there. When the eggs hatch the larvae
start eating the larvae of the host. The sting, due to its length can reach
forward as well as backward, enabling the wasp to sting the mouth of any bird
or lizard that attempts to eat it. The strength of the body wall enables the
wasp to survive an attack by birds or lizards.
 | |
| Spittlebug foam on Ironweed |
 | |
| Spittlebug nymph, foam removed |
 | |
| Two-lined Spittlebug adult |
Spittlebugs
Several Ramblers
saw little globs of white foam on the stems of plants. You also may have seen
them on the grass in your lawn. Called spittle, the clumps of foam are produced
by the nymphal stage of an insect related to cicadas, the spittlebug.
Spittlebugs have piercing, sucking mouthparts that they use to suck fluid from
the vascular system of their host plant. As the plant sap moves through the
digestive tract nutrients are absorbed and the remaining fluid expelled from
the insects anus. It creates the froth by adding mucous to this liquid and
wiggling the end of its abdomen. The frothy mass helps protect the nymph from attack
by predators and parasites which would have to penetrate the sticky mass to get
at the insect inside. There are many species of spittlebugs; the one we saw
today is the Two lined spittlebug and is very common in our area.
 | |
| Common Whitetail Dragonfly (male) |
Dragonflies: On the old gate in the power line right
of way we saw a robber fly and two kinds of dragonflies: Common whitetail and Twelve-spotted
dragonflies. The white upper surface of the abdomen is characteristic of
the mature male Common whitetail. But immature males lack the white coloration
and look like females. The Twelve-spotted dragonfly is appropriately named;
each wing has 3 dark spots. Four wings x 3 spots = 12 spots.
 | |
| Robber Fly |
Robber flies are aerial predators with exceptional
vision and swift flight. They sit on a perch give chase to any small flying
object. They catch it in flight and give it a paralyzing bite. They usually
return to the same perch and finish eating their capture. In the photograph
notice the hairy legs and large, clawed feet. When one of these flies grabs you
you're dinner.
 | |
| Camouflaged looper caterpillar; head is to right spider legs are on far side of body |
Camouflaged looper: Ronnie found an unusual caterpillar on
flowers just inside the Dunson garden. It didn't look like a caterpillar, but
it moved like an inch worm. Closer examination revealed a caterpillar that was
decorated with plant parts and, on one side of the body, spider legs, which you
can see in Don's photograph. The caterpillar feeds on flowers and attaches the trash in the flower head to its body using silk that it spins from its mouth. There must have been the remains of a dead spider on the flower. This is the caterpillar of an inchworm moth,
most likely the Wavy-lined Emerald, Synchlora
aerata. This webpage has several good photos of the
caterpillar.
 | |
| Lynx Spider on flower buds of Tall Thistle |
 | |
| Arrow-shaped Micrathena on its orb web |
Spiders
Some of the
strangest shaped spiders are in the genus Micrathena,
orb weaving spiders whose abdomens are strangely shaped and often decorated
with spines. Nathan found an Arrow-shaped micrathena on its web in
the vegetation.
A Lynx spider is a hunter, not a web
weaver. It hangs out on plants, especially the flowers or flower heads, where
it is wonderfully camouflaged, waiting for prey to come within grasping
distance.
Worms
 | |
| Large earthworm, anterior end to the left Note the absence of a swelling, the clitellum, near the head end. |
Ronnie found a
large, active earthworm moving
across the top of the leaf litter. I've never seen a worm this muscular; it was
difficult to hold and amazingly strong as it wiggled about. Despite its size it
was apparently immature because it lacked a structure called a clitellum that
is present in sexually mature earthworms. The clitellum is a distinct swelling
that appears near the head end of the earthworm, about a dozen or so segments
from the front. It secretes a capsule that holds the worms eggs. To find out
more about earthworms visit this website.
 |
| Red-bellied snake; note faint mid-dorsal line beginning at ring on neck. |
Snake: Nathan caught a small, recently born Red-bellied snake in the Dunson Garden. I first thought that this
was a Ringneck snake, but just as Nathan was releasing it he exclaimed,
"It has a red belly!" That was the tip-off; it was not a Ringneck.
Don's photograph confirms this. Red-bellied snakes can be quite variable in appearance.
Usually the light colored marks just behind the head don't connect to form a
ring, but often they do. Then the snake looks like a Ringneck snake from above,
but the belly of the Ringneck is yellow with a row of small black spots running
down the middle. These belly markings are absent in the Red-bellied snake and
its belly is usually red in color.
Fungi
 | |
| Honey Mushrooms |
We suddenly came upon many clumps of one of the Honey Mushroom species. They were found in beautiful clusters, with
many mushrooms growing from a common center on stipes up to three or four
inches tall. Honey mushrooms, a well known edible fungus, are native to the US
and are usually seen around the base of trees, living or dead. Root-like
underground structures of the fungus attack trees that are weakened by disease
or competition, hastening death and decomposition. Ramblers smelled and tasted
the mushrooms, finding not a hint of honey. It may be that the name derives
from the flow of sap that the infection induces in its victims.
Plants
Walt asked how to distinguish the thin, toothed leaves of
our native Muscadine Grape vine from
English Ivy leaves, which are evergreen and leathery.
 | |
| Saw Greenbrier |
Sue asked about the smilax, which is the Saw Greenbrier (or Catbrier), Smilax bona-nox.
Its leaves are edged with prickles as is the midvein on the lower leaf surface,
and the stems are fiercely prickly. The leaves are often spotted with pale
green. The species’ name “bona-nox” translates as “good night,” a mystery when
applied to this day-blooming vine. But there is a tropical morning-glory with
the same species name. Once known as Ipomoea
bona-nox, this morning-glory is now known as Ipomoea alba, familiar to gardeners as the fragrant,
night-flowering plant, Moon-vine. Its leaves resemble the leaves of our native Smilax bona-nox, hence the shared name.
Sue found a small Maple
Leaf Viburnum growing along the trail. Typical of viburnums its leaves are
opposite and the tiny vegetative bud at the tip of the stem is naked, protected
only by rusty-brown hairs instead of the more typical bud scale.
Near the bottom of the hill, we saw an unusual summer
blooming Rue Anemone.
 |
| White Avens |
At the base of the hill, we also saw several White Avens in bloom. This is one of
two species Linda is most often asked about (the other being Lion’s Paw, Prenanthes). White Avens over-winters
(in our climate) as a rosette of leaves, pressed against the ground, that are
deeply toothed and dissected and suffused with a silvery-white color. But when
the plant flowers in mid-summer, the basal leaves are withered away and the
stem leaves that are present look nothing like the winter leaves. Needless to
say, this is mystifying to the beginning botanist. The flowers produce a
cluster of seed-like fruits with hooked tips that cling to feathers and fur.
Its leaves are food for a wide variety of insects; the flowers provide nectar
to bees, wasps, flies, and beetles that presumably return the favor by
pollinating the flowers.
 | |
| Wingstem |
Out of the woods, we made our way to the power line
right-of-way through an alley of Wingstem plants–probably all three species, Wingstem, Frostweed (aka White Crownbeard), and Southern
Crownbeard. Also in the mix were
several of our native Tall Thistles,
each developing a large bud at the top of the head-high stem. Unlike the much
larger Bull Thistle, Tall Thistle does not have a large, prickly basal leaf
rosette. And, unlike the nasty invasive, Nodding Thistle, Tall Thistle flower
heads are held erect, not nodding.
Southeastern
Wild-rye (once called Eastern Wild-rye) is probably the easiest cool-season
grass to recognize. Its blue-green stems and leaves are distinctive, and the
seed head, with its long upright awns (bristles) is easy to spot. Once mature,
the plant dries to a pale tan and the leaves and seed head persist through the
fall.
 | |
| Rough Sunflower |
On the far side of the ROW, we noticed the first flowers
appearing in a patch of Rough Sunflower.
Jackson-brier
(AKA Lanceleaf greenbrier) vines could be seen draping on the
wingstems and other tall plants in the ROW.
Wild Petunia.
Although its purple flowers somewhat resemble those of the common Garden
Petunia, they are not in the same family. Garden Petunia is in the tomato
family; Wild Petunia is in the Acanthus family.
Several Ramblers stopped at a large patch of Beaked Panic Grass, wondering if it
were a sedge because of its location in the moist floodplain. Linda pointed out
its two-part leaves (sheath and blade) and its round, hollow stem, both of
which usually indicate a grass, not a sedge. The spikelets are also
distinctive, with a prolonged, “beaked” tip.
We saw lots of Virginia
Buttonweed growing in the mown paths of the ROW. Its flowers closely
resemble those of Patridge-berry. They are both members of the Coffee Family,
Rubiaceae.
 |
| Paper wasp feeding on extrafloral nectary (EFN)of Wild Senna The ant was feeding on the EFN above. The EFNs are the round, green bumps at the base of the leaf petioles. |
Extrafloral nectaries (EFNs) are nectar-producing glands
that are not associated with flowers, but are found on leaves and stems. In
most cases, EFNs attract ants that happily lap up the nectar and protect this
source of carbon-rich food by patrolling the plant and attacking or eating other
insects on the plant. The ants are, in
effect, being hired by the plants as body guards, paid in sugar and allowed to
remove caterpillars as fringe benefits. This is a good story and it has been
tested numerous times. Ants are kept from some plants and allowed free access
to others. The damage caused by insect herbivores is measured for each group of
plants. The plants with ant attendants sustain less damage to their leaves and
flowers than plants with no ants.
Wild Senna is
a plant with EFNs on the base of each leaf petiole. We saw both ants and a
paper wasp taking nectar from these nectaries. The presence of the paper wasp
is especially significant. An ant can kill only small caterpillars. If a
caterpillar lives long enough it can grow too large for a single ant to kill it.
Wasps, on the other hand, hunt for protein-rich prey and they can handle larger
caterpillars, stinging them and then chewing them into caterpillar patties for
their larvae to eat.
We saw another Panic Grass, Switch Grass, in the right-of-way as we made our way closer to the
road but noticed the large clumps of Switch Grass that used to grow at the end
of the Dunson Garden had been removed. Switch Grass is one of a handful of
native grass species that have become popular with residential and commercial
landscapers. This is a boon to the many insects that eat its leaves, the birds
that eat its seeds, and many other animals that seek shelter in its large
clumps.
 | |
| American Pokeweed |
The tall American
Pokeweed is still blooming and setting fruit. Although toxic to humans,
some birds and mammals eat the brilliant purple berries, apparently having some
immunity to the poison. The berries make a beautiful dye for woolen yarn but
isn’t “fast” and eventually fades to a dull reddish-brown.
 |
| Japanese Stilt-grass in Dunson Native Flora Garden (It's not native!) |
Japanese
Stilt-grass is getting a hold in the wetlands garden at the west end of
Dunson Garden
SUMMARY OF OBSERVED
SPECIES:
Birds
|
Downy Woodpecker
(feather)
|
Dryobates
pubescens
|
Barred Owl
(feather)
|
Strix
varia
|
|
Mississippi
Kite
|
Ictinia
mississippiensis
|
|
Indigo Bunting
|
Passerina
cyanea
|
|
Common
Yellowthroat
|
Geothlypis
trichas
|
|
Reptiles
|
Red-bellied
Snake
|
Storeria
occiptomaculata
|
Frogs
|
Eastern
Spadefoot
|
Scaphiopus holbrookii
|
Annelids
|
Earthworm
|
Order
Megadrilacea
|
Spiders
|
Green Lynx
Spider
|
Peucetia
viridans
|
Arrow-shaped
Micrathena
|
Micrathena
sagittata
|
|
Insects
|
||
Hymenoptera
|
Velvet
ant (winged male)
|
Dasymutilla
occidentalis?
|
Paper
wasp
|
Polistes sp.
|
|
Red ants
|
Family
Formicidae
|
|
Diptera
|
Robber
fly
|
Family
Asilidae
|
Hemiptera
|
Two-lined
Spittlebug
|
Prosapia
bicincta
|
Orthoptera
|
Field
cricket
|
Family
Gryllidae
|
Lepidoptera
|
Camouflaged
Looper
|
Geometridae:
Synchlora areata
|
Odonata
|
Common Whitetail
|
Plathemis lydia
|
Odonata
|
Twelve-spotted
Skimmer
|
Libellula pulchella
|
Fungi
|
Honey
Mushrooms
|
Armillaria
sp.
|
Flowering
Plants
|
||
Catbrier
|
Smilax
bona-nox
|
|
Maple
leaf Viburnum
|
Viburnum
acerfolium
|
|
Rue Anemone
|
Thalictrum
thalictroides
|
|
White Avens
|
Geum
canadensis
|
|
Wingstem
|
Verbesina
alternifolia
|
|
Yellow Crownbeard
|
Verbesina
occidentalis
|
|
White Crownbeard
|
Verbesina
virginica
|
|
Tall Thistle
|
Cirsium
altissimum
|
|
Southeastern
Wild-rye
|
Elymus
glabriflorus
|
|
Rough Sunflower
|
Helianthus
hirsutus
|
|
Lanceleaf
Greenbrier
|
Smilax
smallii
|
|
Wild Petunia
|
Ruellia
caroliniensis
|
|
Beaked Panicgrass
|
Panicum
anceps
|
|
Virginia Buttonweed
|
Diodia
virginiana
|
|
Wild Senna
|
Senna
marilandica
|
|
Switchgrass
|
Panicum
virgatum
|
|
American Pokeweed
|
Phytolacca
americana
|
|
Cranefly Orchid
|
Tipularia
discolor
|
|
Japanese
Stilt-grass
|
Microsegium
vinineum
|
|
