Thursday, July 3, 2014

July 3 2014 Ramble Report



A larger-than-expected group (20) of ramblers met on this muggy day before the 4th of July. Most of them were expecting to get their feet wet.

Don Hunter's album for today's ramble can be found here.


Today's reading  is a stanza from the poem The Bloody Sire by Robinson Jeffers. It was presented by Dale Hoyt. (The full text of the poem and a recording of the author reading it can be found here. )

What but the wolf’s tooth whittled so fine
The fleet limbs of the antelope?
What but fear winged the birds, and hunger
Jewelled with such eyes the great goshawk’s head?
Violence has been the sire of all the world’s values.

Today's Route:  Through the Flower Gardens to Orange Trail Spur, then down the spur to the creek and left on Orange Trail (away from the river) and back to the upper parking lot.

Parking Lot through the Flower Gardens:

We passed the garden before the international bridge and saw Wild bergamot and Crimson
Plumleaf Azalea
beebalm in bloom. Both plants are heavily visited by bees and hummingbirds. In the pool under the bridge the Lotus are blooming. Further up the walk the Plum-leaf azalea is in bloom. Hugh explained that the conservations of this late blooming, for an azalea, plant was the motivation for the creation of Callaway Gardens, near Pine Mountain, Georgia. Further along we saw that the Hairy Rattleweed was loaded with fruits containing seeds. When they ripen you will be able to hear the origin of its common name. Next we passed the Paw Paw patch and stopped to see if any fruits were still on the trees. These large, sweet fruits are highly desired by many animals and quickly disappear as they approach ripeness. We found three clusters still on the trees, one more than when we last checked on them.

Corn Tassel
We stopped by the corn plants to discuss the function of the tassels and the silk. Many people without an agricultural background don't realize that the tassels and silk are flowers. (Yes, corn is a flowering plant.) The tassels at the top of the plant produce pollen. Since corn is wind pollinated there are no petals to get in the way of the pollen being blown about. The female flowers are found in the "ear" of the
Corn Silk
corn plant. Each one will produce a single fruit which is better known as a kernel of corn. So the ear is really a group of flowers, what botanists refer to as an inflorescence. The only part of the typical plant flower that is left is the pistil. Remember that the pistil is made of three parts: ovary, style and stigma. In corn the kernel is the ovary, the style is the silk and the stigma is the very end of the style. To produce a kernel of corn a pollen grain must land on the stigma and germinate. Germination of the pollen grain occurs when a tube begins to grow from the pollen down inside the style toward the ovary. In the case of corn this pollen tube has to grow about 6-8 inches through the length of a silk before it reaches the ovary. Then it releases its sperm to fertilize the egg cell in the ovary. Without those annoying silks there could be no corn on the cob.

Hugh mentioned that in Illinois teenagers were often hired to de-tassel corn. This is done to produce hybrid corn seed. A hybrid is formed by crossing (mating) two different varieties of corn. But if the tassels are not removed from one of the varieties the plant could self-pollinate. To produce hybrid seed two varieties are planted in rows next to one another and the tassels removed from all the plants in one row. These will be fertilized by pollen from the plants in the adjacent row, so all the corn harvested from the de-tasseled row will be hybrid. (Hybrid corn is much more productive than self-fertilized corn, so it is almost exclusively used in modern agriculture.)

Red-spotted purple butterfly
While we were looking at the corn we noticed a beautiful black butterfly, called a Red-spotted purple, basking in the early morning sun. The upper surface of its hind wings was a metallic bluish-green color. The metallic coloration is not a pigment -- it is a structural color. This is a color produced by the structure of the cells that make up the wing. A characteristic of structural color is that it changes as you look at it from different directions, like the color of an oil slick on water.

Someone asked about why the Red-spotted purple was colored the way it was. It is actually a mimic of another butterfly, the Pipevine Swallowtail. As a caterpillar the Pipevine Swallowtail feeds on plants in the Birthwort family. These plants contain very nasty chemicals that are stored in the body of the Pipevine caterpillar, making not only the caterpillar, but the adult butterfly very distasteful. When a bird eats an adult Pipevine Swallowtail it gags and vomits up its meal. This Swallowtail has dark wings and similar metallic bluish-green hind wings. By looking like the Swallowtail the Red-spotted purple is avoided by birds. (This is an example of what biologists call Batesian mimicry -- the similarity in appearance of two species, one of which is noxious in some way, the other not. The former is the model, the latter the mimic. The phenomenon is named after Henry Wallace Bates, an English naturalist who discovered it.)

To get to the Orange Trail spur we had to squeeze between two groups of Beautyberry plants. These had so many flowers that they will be loaded with purple fruits this fall.

Orange Trail Spur:

We spotted a large Jack-in-the-pulpit with developing fruits. These will turn brilliant red in the fall in the hopes that a passing bird will eat them and disperse the seeds into favorable habitat. Because this plant has three leaves someone asked how to tell it apart from Trillium. In Trillium the three leaves are separated from each other by ~120 degrees. In Jack-in-the-pulpit two of the leaves are separated from each other by 180 degrees and the third leaf is perpendicular to these two, forming an upside down "T."

Nearby we saw very young Hickory saplings and a number of Redbud saplings. Many of the leaves of the Redbud had semi-circular pieces removed from the leaf margin. This is due the activity of leaf mining bees, a solitary bee that uses the leaf fragment to seal the opening to its nest.

In the shady environment by the creek we noticed a beautiful metallic green bodied Ebony Jewelwing Damselfly with very dark wings. These colorful insects are predacious, feeding on other flying insects, like mosquitoes, that they capture in midair and devour. The immature stages live underwater in the creek and are predators also.

Someone asked how Dragonflies and Damselflies were different. When at rest Dragonflies hold their wings horizontally and perpendicular to their body. Resting Damselflies are able to hold their wings together and over their backs. Dragonflies are also much more acrobatic fliers; they can hover, fly forward and backward, and rapidly speed off. They are very difficult, almost impossible, to capture with a net. Damselflies have a weaker, fluttering flight and are not nearly as successful in escaping a net as Dragonflies.

Orange Trail Creek:

Upon reaching the creek we began flipping the rocks along the edge and in the shallows, looking at the underside for attached insects or anything that moved. We were successful in finding Caddis fly larvae, snails and snail eggs, one larval salamander and one recently metamorphosed salamander.

Caddisfly home on underside of rock

Caddis fly adults look like small, hairy brown moths and are commonly attracted to porch lights if you live near a body of water. The larvae resemble caterpillars but construct a "house" made from material in their environment. They inhabit this tube of material and carry it with them whenever they move. Like the Dragonfly and Damselfly larvae they are predators. The Caddisfly larvae we found made houses from plant material and looked like small twigs attached to the bottoms of rocks.

Leopard Frog
We found two Anuran amphibians, one American Toad and one Leopard frog. The toad had a developmental abnormality -- it was missing part of its face.
.
Two salamanders were also discovered under rocks at the
Larval salamander with gills
creek edge. One was still a larva with external gills, feathery structure just behind the head and in front of the forelegs. The other, a newly metamorphosed young adult, was about the same size, but lacked the gills and had larger, more muscular legs,
Newly metamorphosed salamander
especially the hind legs. It is difficult to identify salamanders this young, but these were probably Spotted Dusky Salamanders. They lay their eggs in water and female remains with them until they have hatched. Other species in the same Family of salamanders are fully terrestrial, laying their eggs on land. In these the development is direct from egg to adult with no aquatic stage.

There were lots of small snails found on the underside of
Snail Egg Masses
rocks in the stream and one of the rocks had numerous snail eggs deposited on the underside. Each mass of eggs is surrounded by a clear gelatinous material that resembles the jelly that surrounds frog eggs. There may be 50-100 eggs per mass.

On the way up the trail many different mushrooms were seen, the recent rains stimulating their growth. Of the ones we could immediately identify were the Blackfooted Marasmius and the Split-gill mushroom. Others will be listed here if and when we can identify them from Don Hunter's photographs.

We also noticed several flowers and ferns: Naked-flower Tick-Trefoil, Heal-All, Bloodroot, White Avens and Wild ginger. The Bloodroot and ginger are long past flowering. Broad Beech Fern were very abundant and the reproductive fronds of many of the Christmas ferns have withered.
Lastly, we observed a pair of Daddy-longlegs. These animals are Arthropods but are related (distantly) to spiders in the Class Arachnida. They are classified in their own Order, Opiliones. Unlike spiders, Daddy longlegs are not venomous. They have no venom glands and no fangs, in spite of what urban legends say about them.

After reaching the parking area some of us visited Donderos' for refreshments.
SUMMARY OF OBSERVED SPECIES:

Common Name
Scientific Name
Wild bergamot
Monarda fistulosa
Crimson beebalm
Monarda didyma
Lotus
Nelumbo sp.
Plum leaf azalea
Rhododendron prunifolium
Hairy Rattleweed
Baptisia arachnifera
Paw Paw
Asimina triloba
Red Spotted Purple
Limenitis arthemis
Corn
Zea mays
Beautyberry
Callicarpa americana
Jack-in-the-pulpit
Arisaema triphyllum
Hickory
Carya glabra?
Redbud
Cercis canadensis
Ebony Jewelwing Damselfly
Calopteryx maculata
American Toad
Bufo (Astyanax) americanus
Caddisfly  
Order Trichoptera
Leopard Frog
Rana (Lithobates) sphenocephala
Spotted Dusky Salamander
Desmognathus conanti
Snails
Mollusca: Order Gastropoda
Blackfooted Marasmius 
Naked-flowered Tick-trefoil
Marasmiellus nigripes
Hylodesmum nudiflorum
Heal-All
Prunella vulgaris
Split-gill mushroom
Schizophyllum commune
Bloodroot
Sanguinaria Canadensis
Wild ginger
Hexastylis arifolia
Christmas Fern
Polystichum acrostichoides
Daddy longlegs
Arthropoda: Class Arachnida: Order Opiliones