Saturday, August 23, 2014

August 21 2014 Ramble Report



Twenty three ramblers gathered at 8AM on this relatively cool August morning.

The link to Don Hunter's photo album of today's ramble is here.

Today's reading: Hugh read several quotations from George Washington Carver, all from this source, one of Hugh's favorite blogs. 

There were two announcements of interest to Ramblers:

Emily wanted everyone to know that Sandy Creek Nature Center will be resuming their monthly trail walks, beginning on the first Wednesday in September (Sep. 3). Each walk will start at 9:00 AM and last approximately 1 1/2 hrs. Following the walk, attendees can enjoy free coffee, homemade goodies and conversation in the visitor center.
Date (2014)
Leader
Sept. 3 (Wednesday)
Carmen Champagne
Oct. 1 (Wednesday)
Walt Cook
Nov. 4 (Tuesday)
Dan Williams
Dec. 3 (Wednesday)
Dale Hoyt & Emily Carr

Carmen is one of Sandy Creek's top notch naturalists -- nothing escapes her sight.
Walt Cook was one of the original founders of the Nature Center, as well as a forester and well-known trail creator. (Cook's trail was named in his honor.)
Dan Williams teaches dendrology (the study of trees) at UGA and has authored several books of interest to Ramblers. Many of us have learned how to identify our local trees from Dan. (Look him up on Amazon.)

Bob Ambrose invited everyone interested in Nature-inspired writing to attend the next meeting of the Athens Nature Writing Group which meets on the last Tuesday of the month, 5:30 to 6:30 at the Athens Land Trust offices (located on N. Pope St., next to Emmanuel Episcopal Church). N. Pope St. is off Prince Ave., across from Avid Books. Attendees who can afford to do so donate $5 to help underwrite the Land Trust’s great programs.
Bob will read poems and lead a discussion around the theme "Through the Dark Night, Gently: On Loss, Despair and Pathways to Hope.” Here's a link to some of Bob's poems on the topic.

Bob is one of our Ramblers, an environmental engineer and late-in-life poet. He began writing in 2009 shortly after retirement. He performs monthly in the Athens Word of Mouth open poetry community and was the featured reader for July 2012. Bob also performs at various venues around Athens, including bars, coffee houses, and churches. His poems have been published online at the Athens Word of Mouth website and Bellemeade Books. He has also been published in local soft-bound collections, including “Stray Dog Almanac” and “Proetry” — and in “The Yellowthroat,” the newsletter of the Oconee Rivers Audubon Society. Bob posts on his blog site “Reflections in Poetry.”

Today's route: Through the formal gardens, past the Paw Paws and down to the Butterfly bushes. Then, escaping the heat, we followed the Purple spur trail into the woods and returned to the visitor center via the Purple trail.

Personal note:
Check out the galls!

Many of you know that my birthday was last Tuesday. I thank all of you who sent me birthday greetings -- they were unexpected and very much appreciated. One was especially creative and I felt I had to share it with everyone. 

Zinnias: In the formal part of the garden we stopped to look at a bed of zinnias. Most ramblers know that zinnias are a type of composite -- a member of the Sunflower family. What appears to
Ray florets replace nectar producing disk florets
be a single flower is really a large number of very small flowers (florets) all clustered together. Each petal is, in reality a single floret with a lop-sided strap-like petal. This is termed a ray floret and it is what you plucked off a daisy when you played "She loves me -- she loves me not." The ray florets of the outer whorl are usually sterile and are there to attract the attention of pollinators. The actual fertile florets make up the disk of the inflorescence. In daisies and "unimproved" zinnias there is a single whorl of ray florets and many, many disk florets where nectar and pollen is found (and where seeds are produced). Plant breeders discovered that sometimes they could double the number of ray florets and make a showier flower. The additional ray florets were disk florets that got confused. So the additional "petals" were made at the expense of the part of the flower head that produces pollen and nectar and seeds. The showier the flower the less attractive to pollinators it became. So if you like zinnias and butterflies try to find a heirloom variety. It will be more attractive.

Not a honey bee
Night-blooming Cereus: There is a spectacular cactus in the genus Cereus blooming in the garden. It has enormous
Honeybee with pollen baskets
white blossoms with a huge number of stamens. We noticed it at about 8:30AM and the flowers were still in good shape. Such large, white blossoms that open at night are usually pollinated by bats. While we looked at the flowers we noticed two bees investigating them. One was a honey bee with a lot of pollen in the baskets on its hind legs. The other is not a honey bee, but I don't know what kind it is.

Paw Paw: Further along we stopped at our Paw Paw patch to see if there was any progress in the fruit. Only one fruit is easily visible and it is about the same size as when we last saw it. Adjacent to the Paw Paw is a Winged sumac that is just starting to develop an inflorescence. When mature the sumac berries have a fresh, lemony flavor. The ground fruit makes a wonderful tasting seasoning. It is used in Persian cooking and can be obtained at the DeKalb Farmer's Market in Decatur. (I don't know if it is locally available.)

Skink: Basking on the brickwork we spotted a juvenile skink with a bright blue tail. This could
Juvenile skink
be one of three skink species found in this area: Five-lined skink, Southeastern Five-lined skink or Broadhead skink. The young of all three species look almost identical -- dark body color with five yellow lines running the length of the body and a brilliant blue tail. As the animals mature they gradually lose their yellow lines and blue color on the tail. They are distinguishable by differences in the number and relative size of certain scales, but you have to catch the skink to see these details. All skinks share an unusual characteristic: they can spontaneously drop their tail. The tail vertebrae have a fracture plane and special muscles that, when contracted, break the vertebra along that plane. The tail falls off, twitching violently, attracting attention away from its owner. The tail can regenerate but the new growth differs in appearance, so you can tell when a skink has experienced previous attacks by predators. By the way, skinks are a type of lizard; the term applies to any member of the family Scincidae.

Butterflies

This seems to be a poor year for butterflies, at least they are not as abundant as expected, with
Silver-spotted skipper
the exception of the skippers. We saw four species of skippers and I netted two to pass around. The Silver-spotted skipper is familiar to many ramblers as it is commonly seen nectaring on their garden flowers. It is also easy to identify: it is large for a skipper and has a prominent silvery-white mark on the underside of the hind wing. We also passed around a Long-tailed skipper. This species is a stray, arriving here in the piedmont from the coastal plane, where it is common. As the common name implies, it has elongated tails on the hind wings, so it is easy to identify.

What is a skipper? A skipper is traditionally considered to be a kind of butterfly, but some
Skipper antennae


Butterfly antennae
people insist that they should be given equal rank to butterflies and moths. According to this opinion the Order Lepidoptera should consist of the Butterflies, Skippers and Moths, instead of just Butterflies and Moths. But how do you tell if what you're looking at is a skipper? The one characteristic that is most reliable is the antennae. On a butterfly the antennae are long, segmented and terminate in a swollen end. On a skipper the antennae are like a butterfly's but the swollen end has a pointed hook. Unfortunately, to see this you really need be able to look at the critter close up. Other features that most, but not all, skippers have are: a stocky body with proportionally smaller wings. They just look like husky little butterflies. When these small skipper bask in the sun or while they are sipping nectar from a flower they will often flare out their hind wings, holding them almost horizontally, while the fore wings are only slightly opened.

Sleepy Orange: Here's a website with lots of photos of Sleepy Orange butterflies, giving you a good feel for the range of variation in this species. Different sources give different reasons for the common name: one says it's because they have slower flight than other sulfurs; another says that it's because of a mark on the forewing that looks like a closed eye. Take your pick. The larval food plant for the Sleepy Orange is Senna. We have seen two species of Senna growing here in the garden, S. obtusifolia (Sicklepod) and S. marilandica. Next time we're out we should look for caterpillars.

Tiger Swallowtail: I netted a very dark swallowtail butterfly and was eager to see if it was a Black Swallowtail or a melanic female Tiger Swallowtail. Melanic means that the wings are very
Melanic Tiger Swallowtail
dark due to the deposition of a pigment called melanin, the same pigment that is found in human skin cells. If you hold a dark swallowtail up to the light you can see the shadowy outline of the dark stripes if it's a tiger swallowtail. If you don't see those faint stripes and you know it's not one of the other dark colored swallowtails in our area, then it's a Black Swallowtail. This is a nice example of mimicry. The dark form of the Tiger Swallowtail resembles the Pipevine Swallowtail, a distasteful, perhaps poisonous species. Naive birds that attempt to eat a Pipevine Swallowtail vomit it back up a few minutes after ingestion. When offered a dark colored butterfly that is not poisonous they refuse even to peck at it. (If naive birds are offered a non-distasteful dark swallowtail first they eagerly consume it, so they don't have an instinctive avoidance of those butterflies.) This form of mimicry, where a tasty form resembles a distasteful form was named Batesian mimicry, after the biologist who first proposed it. We have seen other Batesian mimics of the Pipevine swallowtail, the Red-spotted Purple, for example.

Yellow Jacket Hoverfly: We were excited to find another excellent Batesian mimic flying around the flower beds, a Yellow Jacket Hoverfly. Hoverflies (also called Flowerflies) are in the
Antennae are circled
family Syrphidae and the adults are often seen visiting flowers where they eat the pollen. In the process they also pollinate the flower. Their larvae are vigorous consumers of aphids. Many of the hoverflies mimic bees and wasps and the resemblance to those stinging insects is often startlingly real. The appearance also extends to behavior. When I was extricating the fly from the net it started to buzz like a wasp and my first reaction was to release it. If the resemblance is so great how do you know that what you have is a fly and not a yellow jacket? There are several things to look for: the hoverfly can hang motionless in the air, its wings a blur, just like a hummingbird; wasps cannot fly that well. In addition to hovering, it can fly backwards. Another characteristic is the antennae, they are long and obvious in wasps, but the hoverfly has very small, short antennae (see the photo). Lastly, hoverfly eyes are enormous, the meet at the top of the head and occupy most of its space. The eyes of wasps are much smaller.

Cricket: Someone noticed a female cricket and we passed it around so everyone could see
Where's Jiminy when you need him?
the egg-laying tube (ovipositer) and the two "antennae" (anal cerci) at the end of the abdomen. The anal cerci function like antennae -- they have sensory cells that enable the cricket to feel what's going on behind it. The long, needle-like ovipositer is inserted into the soil and a number of eggs travel down its length and emerge at its tip.

Loblolly Pine: At the edge of the woods we noticed a towering Loblolly Pine whose upper branches were covered with green cones. The seed-bearing cones grow high in the tree to facilitate dispersal of the seeds by wind. On the surface of each cone scale there are up to two seeds. Each seed is surrounded by a membranous "wing" that causes the falling seed to be blown a considerable distance from the parent tree. 

Chewed up green pine cones
Further into the woods we saw the cores of several Loblolly cones that had been eaten by squirrels. These were still green, as evidenced by the green color at the tips of the scales. All the seeds had been removed from the cones. In my neighborhood there are several Loblollies with many eaten cones at their feet but there are even more where I have never seen any evidence of cone eating. Out west it has been shown that several generations of squirrels will eat from the same favored tree, ignoring the cones and seeds of nearby pines. The favored trees have lower concentrations of turpentine-like compounds in their tissues, while the concentrations of these compounds is higher in trees whose cones are left uneaten. I wonder is the same is true of our Loblolly pine? This is a project for some enterprising graduate student.

Lespedeza leaves
Lespedeza: At the edge of the path (Purple spur trail) near the eaten cones were some Lespedeza sp. plants. These plants are commonly grow as a hay crop or a cover crop, since they are legumes and can fix nitrogen. They are non-descript, looking like leafy wands. Their family relationships are revealed by the three-leaflet compound leaves that cover the stem. This type of leaf is common in clovers and other legumes; it is called ternately compound or, simply, ternate. Some species of Lespedeza (L. sericea) have proven to be very invasive in the tall grass prairies of the Midwest.

Northern Red Oak: A leafy twig of Northern Red Oak was found on the trail, complete with several developing acorns. Many ramblers have noticed twigs from oaks and other trees littering the grounds and suspect squirrels are the guilty parties. The question is why? Some suggested that they were using the leafy twigs to make their nest. (The squirrel nest, called a drey, is made from such leafy twigs. But why would a squirrel go to the trouble to cut a twig for a nest and then drop it? Plus, if squirrels are the guilty party then there should be evidence of gnawing on the cut end. Another possibility is that the twig has been weakened by the larvae of wood boring beetles eating the woody tissue in the twig. Then when it rains or we have strong winds the twig snaps off at the weakened point. Squirrels are also known to snack on beetle larvae and they may have gnawed into the twig to extract the grub and then let the twig fall. Many hypotheses and questions but few answers!

On our way back to the Visitor center we encountered more of our old friends, the Beech Blight Aphids accompanied by the Sooty Mold growing on their honeydew droppings. Speaking of fungus, we also found a Black footed marasmius growing in a fallen acorn cup instead of its customary twig. Nearby was a juvenile American toad and the outer paper shell of an old Bald-faced Hornet nest. The hornets scrape up wood fibers and mold it with their saliva to construct the paper nest. If you have a nest nearby you can put out colored construction paper and they will incorporate it into their nest as it grows. Change colors every week or so and you'll get a multi-colored nest. These nests only last for one season and are not reused. At the end of the year only the new queens overwinter. All the other inhabitants of the nest, the males, the workers, and the old queen die. Every year the cycle is begun anew.

And then it was time to visit Donderos'.

SUMMARY OF OBSERVED SPECIES:
Common Name
Scientific Name
Zinnias
Zinnia sp.
Flowering cactus
Cereus hildmannianus
Lantanas
Lantana sp.
Blue Salvia
Salvia sp.
Texas Spidewort
Tradescantia reverchonii
Common pawpaw
Asimina triloba
Winged sumac
Rhus copallina
Five lined skink
Southeastern Five-lined skink
or Broadhead skink
Eumeces (Plestiodon) sp.
E. fasciatus, E. inexpectatus,
or E. laticeps
Beetle Larvae
Order Coleoptera
Carpenter ant
Camponotus sp.
Long Tailed Skipper
Urbanus proteus
Silver spotted Skipper
Epargyreus clarus
Yellow Jacket Hoverfly
Milesia virginiensis
Tiger Swallowtail
Papilio glaucus
Sleepy Orange
Abaeis nicippe
Cricket
Family Gryllidae
Ruby Throated Hummingbird
Archilochus colubris
Loblolly pine
Pinus taeda
Lespedeza
Lespedeza sp.
Red Oak tree
Quercus rubra
Caterpillar
Unidentified
Bald Faced Hornets
Dolichovespula maculata
Beech Blight Aphids
Grylloprociphilus imbricator
Black footed marasmius
Marasmiellus nigripes
American Toad
Bufo americanus
Horse sugar
Symplocos tinctoria


3 comments:

  1. One of our shorter list of observed species but also one of the richer and more enjoyable Rambles of the year!

    ReplyDelete
  2. Thank you Dale! I enjoyed learning about so many different insects. Especially the hover flies. I've noticed them for some time now but never knew what they were. Now I do!

    ReplyDelete
    Replies
    1. You're welcome, Andie. Thank you for coming along with us.

      Delete

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