Sunday, July 30, 2017

Ramble Report July 27 2017



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:
Ciné has kicked off a capital campaign to buy their building. Purchase of the property is necessary to secure the future of our beloved community-based cinema and arts venue. Included in their fund raising campaign is the opportunity to "buy" a seat with a donation of $150. A name plate will designate the seat with two lines of text of your choosing.
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

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 (
Tipularia discolor) flowers, so our route today was where the orchid had been seen in years past. Ramblers are most familiar with the Cranefly Orchid in fall and winter, when each plant is visible as a single, oval leaf (2-4 inches long) rising directly from an underground corm. The leaf is dark green on the top surface, rich velvety purple on the lower surface, and pleated and dotted with black warts. The leaf appears in the fall and overwinters, photosynthesizing via the sunlight that shines through the bare canopy. After the canopy leafs out in the spring, the leaf withers and disappears. Then in late July or early August, one leafless flowering stem appears, bearing up to 40 tan to brownish-purple flowers. The spike-like flower cluster is really hard to spot amongst the brown leaf litter from which it emerges. The delicate flower, with its thread-like stalk and narrow spreading petals and sepals, must have reminded an imaginative someone of a cranefly. The flowers are pollinated by noctuid moths.

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

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