Ramble Report August 17 2017

Today's Ramble was led by Dale Hoyt.

The photos in this post, except where noted, came from Don's Facebook album (here's the link).

Today's post was written by Dale Hoyt.

29 Ramblers met today.

Announcements:

1.     Sandy Creek Nature Center begins trail guide training at the end of August. If you enjoy working with children and want to help cure Nature Deficit Disorder this is a

wonderful opportunity. Training is offered from 9 to 12AM on any of these days: Aug. 29, 30 and 31. Get in touch with Kate Mowbray, kate.mowbray@athensclarkecounty.com or 706-613-3615 ext. 231. Many Ramblers are or have been trail guides; ask Emily, Halley, Barbara or Dave, the two Katherines (C and K), Ted and Larry.

2.     Richard provided the solution to the cryptoquote puzzle he posted to the Rambler Facebook page earlier.  “Flowers always make people better, happier and more helpful.  They are sunshine, food and medicine for the soul.”  by Luther Burbank

3.     Jeff brought an aquatic plant, Golden Club, to give to any pond owner who wanted it. It was propagated from one he found in a ditch in south Georgia several years ago.  Katherine was the lucky recipient.

Today's reading: I read some passages from Annie Dillard's essay, Total Eclipse, in her book: Teaching a Stone to Talk. The Atlantic magazine has republished the complete essay. It will be available online until August 22, 2017, so make sure you hop over to the website before this coming Tuesday. Her essay is almost like seeing the eclipse.

Today's route:

From the Visitor Center we walked down the road toward the Lanier Center, stopping at the bottom of the Dunson Garden to look at the Passion vines climbing the deer fence. Then toward the river in the power line right of way, seeking what we found.

Ed's not looking at the Passion vines on the fence, but everyone else is.

Purple Passion-flower vines cover a large section of the deer fence near the bottom of the Dunson Native Flora Garden. To see the flowers you have to come back in the afternoon. This part of the garden is in heavy shade most of the morning and the blossoms only open in sunlight and they only last a single day. The blossoms that look like they are opening were open yesterday and are really wilting. Touch them and they fall off. The green, egg-sized fruits develop

Purple Passion-flower fruit

over the summer and eventually turn yellowish brown as the ripen. Many people think these fruits are the origin of another common name for this plant: Maypop, because if a child stomps on the fruit it may pop. It turns out that this is an example of "folk etymology." The real origin of the name, is revealed in Who Named the Daisy? Who Named the Rose?, by Mary Durant, 1976, Dodd, Mead & Co., NY.

. . . often known by the charming nickname of maypop, but not because it blooms in May. Maypop is the anglicization of the Indian maracock, as the Virginian tribes called it, the name having made its way from the Tupi Indians of South America, up through the Arawak and Carib tribes, and into North America. In the original Tupi, the name was maraca-cui-iba -- the "rattle fruit" – because of the gourd-like fruits whose seeds rattle when the fruit is dried.

The "passion" part of the name does not refer to any aphrodisiac property. It is a reference to the passion of Christ. Early Jesuit missionaries to Brazil in their efforts to convert the native people to Christianity made up symbolic biblical references for the flower parts; e.g., the ten sepals and petals represented the 10 faithful disciples, the three styles the three nails, etc.

The juice of a commercial species of passion flower, Passiflora edulis, is widely used as a flavoring in beverages and ice cream in Latin America. Avis also reports that passion flower tea is an anxiety-reducer.

Gulf Fritillary on Passion vine flowers (Gwillhickers [CC BY 3.0)], via Wikimedia Commons)

Gulf Fritillary emerging from chrysalis; not the silver spangles on the underside of the wings. (Gwillhickers [CC BY 3.0 ], via Wikimedia Commons

Gulf Fritillary egg on tendril

Gulf Fritillary caterpillar

Passion flower vines are hosts to two species of butterflies, the Gulf Fritillary (GF) and the Variegated Fritillary. On Wednesday Emily and I watched Gulf Fritillaries lay their eggs on the vines and we also found GF caterpillars feeding on the leaves. The caterpillars are orange with two dark stripes running the length of their body. As the caterpillar grows the dark stripes become more prominent. Many of the eggs were laid, not on the leaves, but on the tendrils, possibly to reduce the chance that they would be discovered by ants.

The two bumps at the base of the leaf blade are the extra floral nectaries .

Ant getting nectar from extrafloral nectaries

Below the flower base are bracts that have extrafloral nectaries (the green bumps).

Why ants? Passion vines have glands, called extrafloral nectaries (EFN) that produce a sugar solution, i.e., nectar. In the Purple Passion-flower these are found in two locations: at the base of the leaf blade there are a pair of EFN and on the bracts below each flower there are EFN. Why would a plant produce nectar in places far removed from the flowers? The evidence is that the EFN are attractive to ants and when ants are present on the plant the plant suffers less damage from herbivorous insects. As ants patrol the plant looking for nectar they encounter eggs and small caterpillars that they eat. When ants are excluded the plants suffer increased leaf damage. It's an effective defense, but not 100% guaranteed, otherwise we wouldn't see any butterflies.

Cloudless Sulphur caterpillar feeding on Wild Senna flowers.

Passion vines aren't the only plants with EFN. Wild Senna (AKA Maryland Senna) is blooming right now in the power line right of way. Its EFN are located at the base of the leaf petiole, near the stem. Wild Senna is the host plant for two butterfly species: Cloudless Sulphur and Sleepy Orange. We found the yellow and green caterpillars of the former feeding on the flower heads. Their coloration makes it very hard to find them against the background of yellow flowers and green foliage.

Japanese Parasol mushroom

With all the recent rains mushrooms are popping up everywhere, even in the middle of the power line RoW. We spotted a tiny Japanese Parasol mushroom raising its cap in the middle of the grassy area. We need to remember that what we think of as the mushroom is really just a reproductive structure, the equivalent of a flower. The "body" of the mushroom lies out of sight, in the soil or rotting logs or vegetation. That body consists of a network of fine threads, called a mycelium, that grow throughout the substrate, secreting digestive juices and absorbing the resulting nutrients. When the conditions are right the mycelium sends up a mushroom that produces spores by the millions.

The most abundant "weed" in the lower part of the power line RoW is undoubtedly the Wingstems in the genus Verbesina. Wingstems have several thin ridges or "wings" the run the length of their stems. There are three wingstems in the power line RoW and they can be separated by a combination of two features: flower color and leaf arrangement. The species with white flowers, which is just starting to bloom, is White Crownbeard or Frostweed. The other two species have yellow flowers and can be separated by their leaf arrangement: alternate or opposite. Yellow Crownbeard has opposite leaves and Wingstem has alternate leaves. (Opposite leaf arrangement means that leaves emerge from the stems opposite one another. Alternate leaf arrangement means that leaves are unpaired along a stem.)

Rough Leaf Sunflower

Rough Leaf Sunflower has started to bloom in considerable numbers. Its leaves are very rough, both on the top and bottom surfaces. Right now it is the most prominent yellow-flowered plant in the power line RoW.

Silvery Checkerspot butterfly

Silvery Checkerspot caterpillar

The Silvery Checkerspot butterfly is  commonly found in the power line RoW, probably because its larval host plant, Wingstem, is also very common. We found the caterpillar on a Wingstem today.

Cloudless Sulphur butterfly

The Cloudless Sulphur butterfly lays its eggs on Wild Senna and the caterpillar feeds on the flowers, as well as the leaves. It is colored yellow with green and when climbing among the flowers quite difficult to see. The adult butterfly is not a resident this far north because our winters are usually too severe for either the adults, larvae or pupae to survive. This past winter I saw a Cloudless Sulphur flying about in one of those warm January days, so it is possible that as the climate continues to warm they will become permanent residents, just as they are in Florida.

Sleepy Orange butterfly upper surface (By John Flannery from Richmond County, North Carolina, USA - Sleepy Orange, CC BY-SA 2.0, Wikimedia Commons)

Sleepy Orange butterfly (lower wing surface)

Sleepy Orange. The Sleepy Orange is another species that uses the Wild Senna as its larval host. The caterpillar is smaller than the Cloudless Sulphur caterpillar, and green with a yellow line on the sides.

Summer Azure butterfly (By Judy Gallagher CC BY 2.0, Wikimedia Commons)

Summer Azure. There used to be a single species of Azure, the Spring Azure butterfly in North America. But what were considered to be seasonal forms of the Spring Azure are now known to be separate species, as many as nine different one. One of these is the Summer Azure. The underside of the wings of all the Azures are white to gray in color and sprinkled with tiny dark dots. They get their name from the brilliant blue color on the upper surface of the wings, especially the males. Unfortunately, the brilliant color can only be seen when they fly.

The summer azure caterpillar is reported to feed on Wingstem.

Saddleback Caterpillar; beware of the spines

Saddleback Caterpillar. More often felt than seen, the Saddleback Caterpillar is the immature (caterpillar) stage of the Saddleback Caterpillar Moth. The bristly spines carry an intense irritant. Just a slight touch will cause an intense burning sensation. If you've ever brushed against nettles you've experienced a similar effect. These caterpillars eat a wide variety of vegetation, not just the Wingstems that we found this one on. They belong to the Slug moth family, so named because in the caterpillar stage the abdominal legs are replaced by suckers. When they move they glide, rather than walk.

Spittlebug "nest"

Spittlebug nymph; wing buds are lighter green and at mid-body on either side.

Adult Two-lined Spittlebug

Insects: Spittlebugs. People often see small globs of spittle on the stems of various plants. These are produced by the immature stages of, appropriately enough, spittlebugs. Spittlebugs have mouthparts like hypodermic needles. They pierce the stems of plants and are inserted into the vascular system that conducts sap. Plant sap contains sugars and other nutrients, but in low concentrations, so the spittlebug has to suck a lot of sap to get the nutrients it needs. What come in one end goes out the other and this liquid poo is worked up into a frothy mass that covers the spittlebug nymph. This slightly sticky material is thought to protect the enclosed insect from predators.

A common spittlebug in our area is the Two-lined spittlebug, often seen in suburban lawns. The adults are black and have two pink lines that cross their back. They are powerful jumpers and may leap away before you get a good look. We're not certain that Don's photo is the nymph of that species, but we have found adults in the power line RoW on previous Rambles. In the photo of the nymph you can clearly see the developing wings. As the spittlebug grows it molts its skin periodically. With each molt the wing buds get larger. At the final molt the adult wings develop and the spittlebug can now fly in addition to jumping.

Straight-lanced Meadow Katydid (female)

Slender Meadow Katydid (male)

Insects: Orthoptera. Two Katydids were seen in the rank vegetation of the power line RoW. Our ID is tentative: Slender Meadow Katydid (male) and Straight-lanced Meadow Katydid (female). The long, sword-like projection from the end of the abdomen of the female is an ovipositor, a structure used to cut a slit in a plant and deposit an egg or eggs in the opening.

Crab spider on wingstem flower; the spider is on the petal to the left of center

Spinybacked Orb Weaver spider

Yellow Garden spider; the zig-zag silk is the stabilimentum

Spiders. This is time of year when we begin to notice spiders. Just because we notice them now doesn't mean that they haven't been around. They've just been inconspicuous, too small for us to notice, but now they have reached the size where they are easily seen or felt, as when we blunder into their webs. Today we encountered three spiders with similar life styles, but different ways of implementing them: all are sit-and-wait predators. That means that they don't actively search out their prey – they sit and wait for their prey to come to them. Such predatory animals are often camouflaged. For example, a leopard can hide in the brush around a watering hole, its spotted pattern blending in with the shadows and light flecks within the vegetation. The Crab Spider has a similar strategy. It hangs out on flower heads, remaining motionless, awaiting the approach of an insect looking for a sip of nectar. This spider is colored like the flower it sits on and, if you put it on a different flower, it will change its color to match the new background. It takes a few days to change, but, since it doesn't move, it can afford to wait.

The other two spiders, the Yellow Garden Spider and the Spinybacked Orbweaver are web builders (orbweavers) that sit in the center of a capture web of their own construction. The web expands the area they can search for prey. Unlike the Crab Spider that relies on the attractiveness of its flower to draw in prey, web building spiders passively sift the air with their net, trapping any hapless insect that blunders into it, ensnared by sticky threads of silk.

You may have seen the webs of the Yellow Garden Spider in your own yard and wondered about the strip of silk they put in the center of the web, where they sit. This distinct band of silk is called a stabilimentum. The function of this structure is unknown, but one hypothesis is that it warns birds of the presence of the web. The stabilimentum reflects UV light and birds have the ability to see in the UV part of the spectrum. They may avoid tangling up their feathers if they can see there is a web ahead and swerve to avoid it. The benefit to the spider is, of course, that it doesn't have to build a new web every time a bird flies through it.

SUMMARY OF OBSERVED SPECIES:

Flowering Plants
Purple Passion Flower	Passiflora incarnata
Virgin's Bower	Clematis virginiana
Wingstem	Verbesina alternifolia
Yellow Crownbeard	Verbesina occidentalis
White Crownbeard Frostweed	Verbesina virginica
Maryland Senna	Senna mariliandica
Virginia Buttonweed	Diodia virginiana
Carolina Wild Petunia	Ruellia humilis
Rough-leaf Sunflower	Helianthus strumosus
Fungi
Japanese Parasol Mushroom	Coprinus sp.
Vertebrates
Eastern Spadefoot	Scaphiopus holbrookii
Spiders
Crab spider	Family Thomisidae
Black and yellow garden spider	Argiope aurantia
Spinybacked Orbweaver	Gasteracantha cancriformis
Insects
Order Hemiptera -true bugs, cicadas, aphids, plant hoppers
Hemiptera; Family Cercopodidae – Spittlebugs
Two-lined Spittlebug?	?Prosapia bicincta?
Order Lepidoptera –butterflies & moths
Lepidoptera; Family Pieridae –Whites & Sulphurs
Cloudless Sulphur	Phoebis sennae
Sleepy orange	Abaeis nicippe
Lepidoptera; Family Nymphalidae –Brushfooted
Gulf Fritillary	Agraulis vanillae
Silvery Checkerspot	Chlosyne nycteis
Lepidoptera; Family Lycaenidae – Hairstreaks, Blues, Coppers
Summer azure	Celastrina neglecta
Lepidoptera; Family Limacodidae – Slug moths
Saddleback Caterpillar	Acharia stimulea
Lepidoptera; Family Noctuidae – Owlet moths
Black-bordered Lemon	Marimatha nigrofimbria
Order Orthoptera –grasshoppers, katydids, crickets
Orthoptera, Family Tettigoniidae – Katydids
Slender Meadow Katydid	Conocephalus fasciatus
Straight-lanced Meadow Katydid	Conocephalus strictus
Order Hymenoptera –ants, bees, wasps
Hymenoptera, Family Scoliidae – Scoliid wasps
Scoliid wasp	Scolia bicincta