Saturday, March 5, 2016

Ramble Report March 3 2016



Today's report is written by Dale Hoyt.

Here'sthe link to Don's Facebook album of today's Ramble.



Today's reading:

Rosemary read an excerpt from The Essential Guide to Nature Walking in the United States, Charles Cook,1997, p. ix.

The most recommended way of walking?

Do it your way. With walking there's plenty of room for individuality, personal proclivities, and changes in your energy level from one time to another. Walk the way that works best for you.

And what exactly is nature walking? It's any and every kind of walking you can do in the natural world. The activity encompasses strolling, striding, sauntering, stepping, treading, tramping, traipsing, traversing, rambling, roving, roaming, racewalking, hiking, meandering, wandering, wending, pacing, peregrinating, perambulating . . . in natural surroundings.



Next, Bob Ambrose graced us with one of his original creations:

Becoming a Color in Winter
Athens, Georgia
February 29, 2016

Seasons of strong color are gone and now 
the morning dithers. Daylight drains as time 
tilts toward darkness. The world pales, and I 
am left translucent. 

                                     Beneath the weight 
of winter stasis, I would be the bare terrain 

of earth-ochre mudded with umber stain 
suffused in amber overtones that streak 
the fields of muted tan with mellow shades 
of faded sun. 

                                     Emerging from a 
winter storm, I would be the silent gleam 

of snow-white capped with crystal sheen 
and sculpted crust on evergreens when lit 
against the clear embrace of air condensed 
on Arctic ice. 

                                    Within an endless 
winter night, I would be the burning soul 

of fire-bright fused with shimmering gold 
seared to shear irradiant glow above a bed 
of hissing embers anchored by layers of 
burnt-orange ash.

                                    Against the bitter 
edge of winter, I would be a languid dream 

of sea-green tinged with deep blue hues lit 
within by see-through silver, framed by a 
sunbeam slicing through storms that rumble 
beyond the horizon.



Today's route: We took the mulched path from the parking lot to the cement walkway in the shade garden. At the bottom of the walkway we entered the Dunson Native Flora Garden, proceeded through it and then to the temporary pool in the power line right-of-way. We then followed the Orange trail downstream to the Orange trail spur which we took back to the parking lot.


Cement walkway


Hazelnut catkins
On the left side of the walkway there is an American filbert (AKA hazelnut) with multiple stems. Hanging from the upper twigs are numerous long, cylindrical catkins. A catkin is a long, dangling group of unisexual flowers, in this case male, that are found on a number of different kinds of trees and shrubs. Some trees (e.g., willows) also produce female catkins. The flowers that make up a catkin usually lack petals. Catkins will appear later in the spring on Oaks, Birches, Hornbeams, Alders and other trees. Dangling from their twigs catkins swing and sway with the gentlest breezes, shaking their pollen into the wind which carries it away. Hopefully the pollen will land on a female flower. This is a haphazard way to make hazelnuts or acorns, so these trees have to produce copious quantities of pollen to be assured of producing offspring. If your eyes itch and redden in the spring you have the catkins to blame.

Japanese witch hazel flowers
Just beyond the hazelnut are Japanese witch hazels, small shrubby trees that still have open flowers. But both the Japanese and American species are unusual in that they begin to flower in late fall and keep flowering during the winter. This would seem to be a foolish thing for a plant to do. Flowers with petals are designed to attract pollinators, but where are the pollinators in the middle of winter? Only a few insects are active in winter and one kind, known as "winter moths," may pollinate witch hazels. Winter moths fly at night and are active even when the air temperature is in the 30s, so they are prime candidates as pollinators. On sunny late fall afternoons I have also seen yellow jackets and flies visiting the flowers of the American witch hazel, so they could also be important pollinators.

Don located a fallen Northern red oak leaf with the black blotches that are caused by a fungus, Tubakia dryina, no common name.

Dunson Native Flower Garden

Chattahoochie trillium
Things are beginning to happen in the DNFG. Already some Trilliums are up with developing flower buds and a couple of them are currently blooming. Most that we saw today are Chattahoochee Trillium; they have a very prominent light green stripe running down the middle of each leaf. There are no naturally occurring Trilliums in the State Botanical Garden. Those in the DNFG have brought in from other places in Georgia.
Hybrid trillium (?)

Many of these do not naturally occur together so they have the opportunity to hybridize here and some that we see appear to be hybrids. The DNFG is also probably the source of Trilliums that appear elsewhere in the Garden. An example is the Trillium we found on the Scout trail last week. Trilliums and many other spring ephemeral plants produce seeds with energy-rich fatty "handles" called elaiosomes. These are very attractive to ants, which carry the seed back to their nest. There they strip off the elaiosome to feed to their nestmates. The seed is carried away and discarded in the nest's trash heap. So ants are an important disperser of these seeds. Yellowjacket wasps have also been observed removing seeds from Trilliums to carry back to their nests. They are more likely to be responsible for extra long distance dispersal of the plant.

The first bed we walk past has what looks like grass coming up. In reality, these are the early leaves of Spring Beauties and they will not produce flowers for a few more weeks.

Trout lily leaves emerging from leaf litter
At the base of a large tree we noticed the emerging leaves of numerous Trout lilies. There are two species of Trout lilies planted in the DNFG. Yellow trout lilies that form large, even massive, colonies of plants, all of which are clones of the original founders, and Dimpled trout lillies, that bloom later and do not form clonal colonies. Further on we found a blooming Yellow trout lily growing in the soil remaining on an upturned stump. We have seen this same plant for the last five years.

Southern Maidenhair fern
In the rock lined stream bed we located a newly emerged Southern maiden hair fern and, just past the stream where the path turns sharply to the right we stopped to look at the buds on the Ashe magnolia. They still show no signs of swelling.

Golden ragwort
Several clumps of Golden ragwort have started blooming. The unopened buds have a blush of purple. Several ramblers noticed that the leaves of Little brown jugs are sometimes very deep purple. These are the leaves that overwintered. The purple color is due to compounds called anthocyanins that are produced in the leaves. It is thought that these purple pigments protect the photosynthetic apparatus from damage by ultraviolet light. In summer, when temperatures are higher, plants can make chlorophyll and the other molecules for photosynthesis much faster than they can in the winter. That makes it easier for them to replace the material damaged by UV radiation in the summer. But in the winter the chemical reactions that repair UV damage are much slower, so having a purple sunscreen is thought to reduce the amount of damage, allowing photosynthesis to occur even at cooler temperatures. Plus, it's not just winter where we see purple in the leaves. New growth in the spring is often colored with anthocyanin. Look at the emerging leaves of oak trees this spring and you'll find them tinted with light red pigment.

Leatherwood is still blooming, as it was two weeks ago, but now it's first leaves have begun to appear.

Spicebush pistillate (female) flowers

Spicebush staminate (male) flowers
Spicebush flowers were easy to miss. At first glance they resemble the flowers of the leatherwood, but there are important differences. Spicebush is a dioecious (pronounced: die-E-shus)plant, meaning that the plant has separate sexes; all the flowers on one plant are either male or female, but not both. The typical flowering plant produces flowers that have both male and female structures – the stamens, which produce pollen, and the pistil(s) which produce fruit and its contained seed. Plants that produce such flowers are called hermaphroditic and the flowers are called bisexual or perfect. A single plant that produces unisexual flowers of both kinds is called monoecious. Examples of monoecious plants are squash and corn.

Why be dioecious? Hermaphroditic and monoecious plants run the risk of self-fertilization but a dioecious plant can never self-fertilize. Self-fertilization or selfing, is a bad idea because the chance of producing defective offspring is greater. The down side of being dioecious is that the plant must have another plant of the opposite sex available as a mate. Without a nearby female all the male pollen would be wasted. Similarly, without a nearby pollen source the female would not be able to produce seed.

Yellow wood poppy

Virginia bluebells
Also seen in the DNFG were a single yellow wood poppy blossom and a few flowers of Virginia bluebells peeking up through the leaf litter.

Painted buckeye leaves and flower buds emerging
Painted buckeyes had all stages of bud development, some with leaves fully emerged but not yet expanded. A careful look into the heart of these leafy clusters reveals the beginning of the flower shoots that will develop over the next few weeks.

Toward the bottom of the DNFG George spotted a large Cypress tree with things that looked like catkins hanging from the ends of the branches. I was reluctant to call these catkins because Cypress is not a flowering plant. It is a Gymnosperm, the group that includes the pines, junipers, redwoods, firs and many others. The reproductive structures in Gymnosperms are usually called cones.But I found several books that call the Cypress reproductive strutures catkins, even if they are made of cones and not flowers, so I'll get off my high horse. Even if they are not true catkins they function in the same way. As long as we understand what a structure does we can be flexible about what it is called or we fall into the Professor Twist trap:

The Purist (by Ogden Nash)

I give you now Professor Twist,
A conscientious scientist,
Trustees exclaimed, "He never bungles!"
And sent him off to distant jungles.
Camped on a tropic riverside,
One day he missed his loving bride.
She had, the guide informed him later,
Been eaten by an alligator.
Professor Twist could not but smile.
"You mean," he said, "a crocodile."

Linda added more to the story about Cypress "catkins": "The dangly things at the ends of the bald cypress at the end of Dunson are, yes, "male" pollen-producing cones, but they are not "last year's" as I said.  Turns out that these "tassels" are produced in late summer and fall, and are dormant through the winter, then "ripen" in early spring, when they release the pollen before leaves appear.  "Female" cones are also produced at the same time in the same area at the end of the twig and become fertile about the same time in the early spring.  Ah, the ever various ways of plants...."

Highbush blueberry flower buds
Leaving the DNFG we found two High bush Blueberries by the fence. Both had many candy-striped flower buds ready to open and some that were actually open. But no pollinators are in sight. One of the consequences of climate change that biologists worry about is mismatches in the timing of natural cycles. Plants depend on pollinators being present at the same time the flowers bloom. With unseasonably warm weather plant flowering and the emergence of pollinators may get out of sync, resulting in lower amounts of fruit and seeds being produced. Highbush blueberries need bumblebees for efficient pollination. Bumblebees shake the pollen out of the flower by using "buzz" pollination. The bee grabs the flower and rapidly vibrates its wing muscles (without actually moving its wings), making a buzzing sound. The vibration shakes pollen out of the flower and some sticks to the hairy body of the bumblebee. If bumblebees fail to emerge when the blueberries flower the crop will be diminished or fail.

Power line

Tadpoles, probably Southern Leopard frog
Two weeks ago we saw frog and toad eggs in a temporary pool in the power line right-of-way. The eggs have now hatched and many of the tadpoles were clustered at the edge of the pool, resting on the bottom or clinging to the vegetation. There were certainly thousands and possibly tens of thousands of tadpoles there today. Most were probably the offspring of the Southern Leopard frogs. 

Several people wanted to know what tadpoles eat. They are almost 100% vegetarian, eating algae and scraping off the outer layers of green vegetation and bacterial films that grow on submerged objects. If they encounter a dead or dying tadpole they will eat it. In some species a few individuals become cannibalistic. The remarkable thing is that the adult frogs and toads feed on insects. During metamorphosis the entire digestive physiology changes. The gut decreases in length and the type of digestive enzymes change.

Ostracod

Planarian
There are a great variety of other creatures that live in this temporary pool. A small scoop of water contained several kinds of tiny crustaceans: ostracods and copepods.

Ostracods are commonly called clam shrimp or seed shrimp because they resemble tiny seeds or very tiny clams or mussels. To the naked eye they look like tiny specks hustling about the water in a jerky motion. Copepods have no common name (except copepod). They are very transparent and difficult to see with the naked eye. They are longer and thinner than ostracods. The water sample also contained several flatworms which some of you might remember from your biology class – Planaria. There was also a long, transparent unsegmented worm that could be either a nematode or a nematomorphan (a horsehair worm).

Orange trail along river

Look! No privet!
I'd like to periodically visit this area in the Garden just to see what happens after all the privet was removed. It was so dense that removing it revealed ground with almost no vegetation present. That was last year. This spring we will begin to see the plants that are able to colonize bare soil. 

Winged elm flowers
There is a large winged elm that is flowering at the edge of the woods. The stamens on the flower have a light purply-orange color that Linda describes as mauve. When they are massed together the whole tree seems to glow. Winged elm is one of the first trees, along with red maple, to bloom in the spring.
A ragwort, possibly Butterweed
One of the early invaders of the soil where the privet has been removed is a plant that forms large basal rosettes of healthy, dark green leaves. They reminded me of the leaves of ragwort, but they are not blooming yet, so we had a difficult time identifying them. We now think they might be Butterweed, a type of ragwort, but we'll have to wait for the flowers to appear to be certain.

One of the first large trees we noticed has bright green shoots emerging from the lower trunk, an indication that it may be diseased. We were lucky to have these adventitious shoots to look at because it clearly indicated that we had a Box elder – a maple that has pinnately compound leaves (usually three leaflets per leaf, but the number is variable, ranging from 1 to 7.) The key characteristic is discovered by looking at the buds – they are opposite one another. Also the leaf scars make tent-shaped marks that completely encircle the stem. That is unique to box elder.

Orange spur trail

Ground ivy (AKA Gill over the ground; Ale hoof)
Time was getting late so we rushed back toward the parking lot but still had time to notice the Ground ivy growing abundantly on either side of the spur trail. Ground ivy is known by other names: Gill over the ground, which refers to its sprawling growth habit and ale hoof, an old Anglo-Saxon name. Both refer one of its early uses which was to preserve beer. The leaves of ground ivy were added to fermented beverages to extend their shelf life. Ground ivy is in the mint family and the mints all have a variety of chemicals in their leaves that give them characteristic odors and flavors. The name "ale hoof" refers to that usage, the hoof part meaning simply ivy. But what about "gill over the ground?" One suggestion is that "gill" is from the French guiller which means to ferment. Ground ivy was later replaced by hops in flavoring beer and the pasteurization process solved the shelf life problem.

Rue Anemone
We also noticed a solitary Bloodroot on the hillside to the right. Perhaps there will be more later. Where the spur trail turns to right we checked on Rue anemones that we saw two weeks ago – there seems to more of them today.

We finally returned to the parking area and some of us adjourned to Donderos' for our customary coffee and conversation.

SUMMARY OF OBSERVED SPECIES:

American filbert/hazelnut
Corylus americana
Japanese witch hazel
Hamamelis japonica
Leaf spot fungus
Tubakia dryina
Leatherwood
Dirca palustris
Chattahoochee trillium
Trillium decipiens
Spring beauty
Claytonia virginica
Southern maidenhair fern
Adiantum capillus-veneris
American trout lily
Erythronium americanum
Ashe's magnolia
Magnolia asheii
Golden ragwort
Packera aurea
Green-and-Gold
Chrysogonum virginianum
Wild ginger
Hexastylis arifolia
Trillium hybrid
T. discolor x T. decipiens?
Virginia bluebells
Mertensia virginica
Spicebush
Lindera benzoin
Yellow wood poppy
Stylophorum diphyllum
Cranefly orchid
Tipularia discolor
Painted buckeye
Aesculus sylvatica
High bush blueberry
Vaccinium corymbosum
Great blue heron
Ardea herodias
Ground ivy
Glechoma hederacea
Aquatic worm
Phylum Nematomorpha or Nematoda
Southern leopard frog
Rana sphenocephala
Mosquito larva
Family Culicidae
Ostracods
Arthropoda: Ostracoda
Daphnia (water flea)
Daphnia sp.
Planarian flatworm
Platyhelminthes: Trematoda
Blackberry
Rubus sp.
Winged elm
Ulmus alata
Box elder
Acer negundo
Bloodroot
Sanguinaria canadensis
Rue anemone
Thalictrum thalictroides

 



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