Today's Ramble was led by Dale Hoyt.
Here's the link
to Don's Facebook album for today's Ramble. (All the photos in this post are
compliments of Don, unless otherwise credited.)
Today's post was written by Dale Hoyt.
Today’s Focus:
A nice walk in the woods
22 Ramblers met today.
Announcements:
- Bob told us that his new granddaughter was born this morning.
- Don said next Wednesday and Thursday mornings the forecast is for subfreezing temperatures – optimal for frost flowers! If you don’t know what a frost flower is visit this website. Don will, tentatively, be at Sandy Creek Nature Center next Wednesday morning around 7:45 to photograph the frost flowers and show them to anyone. He will also be at the bottom of the Dunson Garden on Thursday morning at around 7:45 to check out the Gardens frost flowers. This is subject to the forecast holding; Don will notify us early next week if his plans change.
- Linda is now getting around with a boot, even driving, and visited our social hour today.
- Betsy introduced one of her grandchildren, Bowen, Clay’s little brother.
 |
| White Oak acorns; the white structures are the beginnings of roots. Acorns from trees in the white oak group germinate in the fall soon after they hit the ground. |
Show &
Tell: Dale brought a
dozen White Oak acorns collected 4-5 days ago and placed in a plastic
container. Many of them germinated while setting on the dining room table –
they have white roots, some almost an inch long. Acorns from the red oak group won’t
germinate until spring.
Today's reading:
Dale read the October 30th entry from Donald Culross Peattie’s An
Almanac for Moderns:
THE day was gray; the wet wind
blew the morning long; but in the afternoon the sun came forth in clear green
gold, sinking to the blue of distant hills, and cast a forlorn radiance on the
burnished copper of the autumn grasses and the bells of purple false foxglove.
I heard the meadow cricket
shuffling his harsh, folded wings with the stiff sound of a fan flung open. The
common locusts flitted before me with a snapping whir, dropping to the ground
again, after a few zig-zag turns. But the leather-wings darted wildly away,
flinging themselves toward fiery sunset glow as if they were bent on dying in
it.
A sense of the end of things,
the last. Of a chant of death, of a final sigh of warmth from the earth. Of
frost to come.
Today's
Route: We walked to the Purple Trail which we took
to the river, turned left (downstream) on the Orange Trail, around the Beaver
Marsh and returned to the Visitor’s Center via the Orange Trail Spur.
REMEMBER: Click on any photo to enlarge it.
 | |
| Ginkgo leaves changing color On this tree the edges of the leaf remain green while the center turns yellow. |
Ginkgo leaf color change. In last week’s post I
wondered how variable the leaf color change was in our Ginkgo trees, so we paid
special attention to it today. One of the four trees had leaves with yellow
centers, green around the periphery. Other trees were turning yellow close to
the petiole or remaining green close to the petiole. I still hope those of you
with a Ginkgo in your neighborhood will report to me on its color change
pattern. Thank you in advance.
 |
| Two-wing Silverbell; the fruits are the dark brown structures hanging downward. |
 | |
| Closeup of Two-wing Silverbell fruit showing the two prominent wings. |
The fruits of the Two-wing Silverbell appeared, at
first glance, to be fungus infected leaves, dark and dangling from the twigs.
The fruit have two major wings and two minor wings (almost non-existent),
compared to the four-winged fruit of the Carolina Silverbell. Both species of
Silverbell are found in Georgia, but the Two-wing is restricted to the coastal
plain. The Carolina can be found growing wild in the Garden’s natural areas. (photos
of leaves and fruit)
The Bottlebrush Buckeye is mostly found in
Alabama, only barely making it across the Georgia state line. It still retains
most of its leaves, unlike the other, shrubby Buckeyes that are native to our
state. They (Red Buckeye and Painted Buckeye) dropped their leaves weeks ago.
The Red and Painted buckeyes are among the first woody plants to break bud in
the spring and, also, the first to shed their leaves in autumn.
 | |||
| Chinese Witch Hazel flowers Like its American cousin, it blooms in fall and winter. |
A Chinese Witch Hazel is currently blooming. The
flowers have stringy, yellow petals and resemble those of our native American
Witch Hazel. In previous weeks we have searched for the flowers on those plants
with no success.
 |
| Beech Drops; parasitic on Beech roots. |
 | |
| Closeup of Beech Drops showing flower buds. |
Beech Drops is a flowering plant that is parasitic
on the roots of American Beech trees, so you will find them around Beeches.
Because they obtain all their nourishment from the Beech tree they have no need
for chlorophyll and look like dead twigs projecting from the ground. The
swellings are flower buds from which seed capsules will develop. The lower
flower buds never open; they self-fertilize. Only the upper buds open and can
be cross-pollinated. They don’t seem to harm their host tree – we have seen
them under the same trees for the last nine years.
A Compound leaf is defined as a leaf separated
into two or more distinct leaflets. The crude diagram below may help you
visualize how a simple leaf differs from a compound leaf.
 |
| Diagram of a compound leaf (L) and a simple leaf (R) |
A simple leaf
consists of a leaf blade (the green part) attached to a twig. At the place
where the leaf is attached there is a swollen bump, called a bud. (It is more
properly called an axillary bud, because the bud sits in the axilla of where
the leaf is attached to the twig. Axilla is the Latin word for armpit.) A
compound leaf is divided into two or more leaflets (five in the diagram). The
point is that the leaf is everything that is attached to a twig and has a bud
at its point of attachment. (The bud contains, in embryonic form, next years
twig, leaf, or flower.)
Compound leaves are found on a variety of different trees
native to our area: hickories, green and white ashes, pecan, black locust,
honey locust, black walnut, boxelder and mountain ash. There are also shrubs
with compound leaves: sumacs, elder berry and devil’s walking stick.
 |
| A young hickory with 3 compound leaves; each leaf has five leaflets. |
The small sapling in the photo above is a hickory, probably either
a Pignut or a Red Hickory. It has a thin petiole (the petiole is the stalk
of the leaf that is attached to the twig). The other common hickory in the Garden is the Mockernut
which has a stouter petiole.
A question that is often asked is, “Why do some trees
have compound leaves and others don’t?” Or, phrased in a different way, “What
is the adaptive advantage of compound leaves?”
As is usual in biology, this type of question is
difficult to answer, in part because there is no satisfactory way of testing
the answer. This has not prevented people from speculating and one of the more
interesting ideas is that a compound leaf can be viewed as a cheap, disposable
branch.
A tree branch is woody and has a lot of supportive
structural material that is not found in a leaf. In arid conditions it would be
less expensive to drop a leaf than a branch in conditions where reducing water
loss became important. If that is the case then you would expect to find more
plants with compound leaves growing in dry environments like deserts,
grasslands and savannahs. And you do. In North American deserts you find
mesquites, acacias and paloverdes that all have compound leaves. In more temperate
climates it is less likely to matter what kind of leaf a tree has and you find
fewer species with compound leaves.
 |
| The very dark tree trunk in the background is a large Persimmon. We have never found any fruits, so we think it is a male tree. |
There is a large Persimmon to the right of the
trail at the point where the Purple Trail turns sharply to the left. Hugh
Nourse, the first leader of the Nature Ramblers thought this tree was probably
the largest of its kind in the Garden. Persimmons have very dark, blocky bark.
Here are the birds, either seen or heard on today’s
Ramble:
Hermit Thrush, Yellow-bellied
Sapsucker, Red-shouldered Hawk, Carolina Wren, Blue Jay, Brown Thrasher,
Cardinal, White-throated Sparrow and Red-bellied Woodpecker
One of our astute Ramblers,
Brown, spied a Cardinal in the act of eating seeds from a Musclewood tree. The
seeds are enclosed in leaf-like structures, so it takes a little effort to get
them out. But the Cardinal has a large bill that is capable of cutting through
much tougher fruits to get at the seeds within.
(photo of the flowers high in
the tree)
Mushrooms encountered today:
 |
| Crowded Parchment Fungus on lower surface of branch (in contact with ground). |
 |
| Crowded Parchment Fungus on exposed surface of branch. |
Crowded Parchment Fungus is often found on
fallen wood. It is a wood decomposer that assumes different shapes, depending
on where it is growing. On the undersurface of a piece of wood it forms a flat
surface, but, on the sides, it extends away from the branch and assumes a form similar
to a thin False Turkeytail mushroom. It is widespread and common on fallen
branches.
Puffballs are a type of mushroom that usually lack
stems and have no distinct caps. (Ordinary mushrooms, like the portobellos you
get from a grocery store, have a stem with a cap. The underside of the cap has gills
that release spores.)
The puffballs in Don’s photo are are Pear-shaped
Puffballs and are unusual in that they are growing on wood. Most puffballs
grow on the ground. They have white flesh and are edible before they begin to
produce spores. As they age they become darker in color and the outer skin
becomes tougher, with an opening developing at the top. Inside the solid white
flesh begins to produce brown spores. When mature any disturbance of the outer
shell, like a falling rain drop or the finger of a curious child, causes a puff
of brown spores to be emitted from the top opening. (That’s why they are called
“puffballs.”).
 |
| Pear-shaped Puffballs and Biscogniauxia Fungus (the black surface). |
In the photo of the puffballs you will notice an area
that appears to be painted black. That black surface is a fungus we identified as a Hypoxylon. Dr. Jean Lodge supplied this information:
That black surface is a fungus called
Hypoxylon, which is deadly when it infects living trees. It kills the trees and
continues to digest the dead wood. Correction by Dr. Jean Lodge: The photo of the ‘Hypoxylon’ is Biscogniauxia atropunctata (Schwein.) Pouzar, previously classified in Hypoxylon. The fungus is popping the bark off, which is not a characteristic of Hypoxylon. Hypoxylon is not usually an aggressive pathogen, but some Biscogniauxia can be (not all), so there are a lot of caveats on this one.
 |
| Hornbeam Disk fungi on Hophornbeam bark. |
 |
| Gilled Polypore, showing the "gills" |
 | |
| Upper surface of the Gilled Polypore |
Gilled Polypore growing on wood on the ground. Most
polypore fungi release their spores from tubes and the underside of the fruiting
body. In the Gilled Polypore the tubes are extremely oval shaped, so much so,
that they look like messy gills.
 | ||||||
| False Turkeytail |
First, you need to know (or remember)
that mushrooms are the fungal equivalent of flowers. Just as a flower is
produced by a plant, a mushroom is produced by a fungus. In flowering plants
the body (roots, stems, leaves) of the plant provides the nutrients to produce
the flowers and, ultimately, the seeds. In a mushroom-producing fungus the part
corresponding the roots, stems and leaves is the mycelium. It looks very
different from a plant and I'm sure that you've seen a mycelium before. When bread gets moldy
the fine, white threads you see surrounding the colored molds are the mycelium
of the mold. Similarly the wood-rotting mushrooms have fine threads the
penetrate everywhere in the wood, secreting digestive juices that break down
the wood fibers and then absorbing those digestive products. To produce a
mushroom the mycelium must acquire enough energy from its log (or whatever it
is rotting). But that is not enough. The mycelium has to meet and fuse with a mycelium of
the same species but a different sex. If the mycelium doesn't meet that different sex it can't produce a mushroom.
Notice how different this is from a flowering plant. The plant produces a flower, hoping that it will receive pollen to allow it to make seeds. The fungus mates with a different sex and hopes conditions will permit them to produce a mushroom. Note also that I said "different" sex, not opposite sex. That's because fungi have more than two sexes. Some have thousands of different sexes.
So most mushrooms are the result of a sexual
act. But mushrooms do it a lot differently than other organisms. There is
nothing like easily recognizable male and female fungi, and a fungus doesn't
mate with just any other fungus. Fungal sexes are separated into what are
called "mating types." In order to produce a mushroom the mycelium of one individual must fuse with the mycelium of a
different mating type. The mating types are not visibly different. They can be
determined in the laboratory by whether or not two mycelia can fuse. If they
can't, they are the same mating type. If they can, they were different mating
types and the fused portions will go on to produce a fruiting body.
At the bottom of the purple trail are two trees with very similar leaves, but oh so different bark. Musclewood and Hophornbeam. Musclewood is restricted to wet environments and grows near rivers and streams. Hophornbeam has wider tolerances. It grows from streamside to dry ridges. The bark of Musclewood is gray and smooth, but the underlying trunk is best described as "sinewy," like a muscular arm. Hophornbeam has bark that is brown and arranged in narrow vertical strips, as if a cat had scratched it.
 |
| Musclewood (AKA Ironwood) showing the sinewy trunk. |
 |
| Hophornbeam showing the "cat scratch" bark. |
Film on water surface of Beaver Marsh
Many people have seen a scum on the surface of a lake,
pond or slow-moving portions of a creek. Most of them assume that it is some
form of pollution like motor oil. But such scums are also produced naturally by
the decay of vegetation in the water. There is an easy way to determine if the
scum is an oil slick or a biofilm: find a stick and poke it into the scum,
moving it about a little bit. An oil slick will reform but a biofilm will break
apart into pieces like a thin sheet of glass breaking.
 | |
| Christmas Fern |
 |
| Christmas Fern; closeup of frond showing the Christmas stocking shape of the pinnae. |
 | |
| Christmas Fern; underside of the fertile section of a frond. The brown spots are sori, aggregations of spore-producing sporangea. |
Some Christmas Ferns with new growth were seen next to
the path. This fern is one of the commonest in the Garden. Only some of the
fronds are fertile, i.e., produce spores. The fertile fronds are longer and the
pinnae on the terminal third or fourth are abruptly smaller. The spore
producing structures are on the underside of these smaller pinnae. They look like
brown dots. Each dot is a called a sorus (plural: sori) and consists of many
sporangia, the actual spore producing structures.
 | |
| Creek Chubs |
Small fish are often seen in the deeper pools of the
Orange Trail creek. The photo is of Creek Chubs. (Identification made by
Dr. Bud Freeman, Curator of Fishes and Director of the Georgia Museum of
Natural History.)
 | |
| Leaves of Round-Lobed Hepatica; this plant my bloom as early as January. |
Round-lobed Hepatica leaves are very fresh. They will stay
green throughout the winter and finally be replaced by new leaves next spring.
They are usually referred to as “Spring ephemerals,” but, strictly speaking, a
Spring ephemeral does not have a leaf present all year, just in a brief period
in spring, before the tree canopy closes.
 | |
| A Planthopper, family Flattidae Planthoppers are related to aphids and suck the juices from plants in a similar way. |
 |
| Unusually warty bark of an American Beech tree. |
One of the American Beech trees near the upper end of the
Orange Trail Spur has three main trunks, two of which are covered with “warts.”
No other beech trees in the Garden have such warts and we are always mystified
when we see them. Internet searches bring up pages with Beech Bark disease, but
that disease looks very different than our warty tree, so it is unlikely to be
dying. Besides, it hasn’t shown any sign of poor health in our nine years of
rambling.
SUMMARY OF OBSERVED SPECIES:
Ginkgo
|
Ginkgo biloba
|
Two-wing Silverbell
|
Halesia diptera
|
Bottlebrush Buckeye
|
Aesculus parviflora
|
Chinese Witch Hazel
|
Hamamelis mollis
|
Hop Hornbeam Disc fungus
|
Aleurodiscus oakesii
|
Pignut Hickory or Red Hickory
|
Carya glabra or C. ovalis
|
American Persimmon
|
Diospyros virginiana
|
Crowded Parchment Fungus
|
Stereum complicatum
|
Pear-shaped Puffball
|
Lycoperdon pyriforme
|
Biscogniauxia fungus
|
Biscogniauxia atropunctatum
|
Mustard Yellow Polypore
|
Fuscoporia gilva
|
Cranefly Orchid
|
Tipularia discolor
|
Sourwood
|
Oxydendrum arboreum
|
Beechdrops
|
Epifagus virginiana
|
Hermit
Thrush
|
Catharus guttatus
|
Yellow-bellied
Sapsucker
|
Sphyrapicus varius
|
Red-shouldered
Hawk
|
Buteo lineatus
|
Carolina
Wren
|
Thryothorus ludovicianus
|
Blue
Jay
|
Cyanocitta cristata
|
Brown
Thrasher
|
Toxostoma rufum
|
Northern
Cardinal
|
Cardinalis cardinalis
|
False
Turkeytail
|
Stereum ostrea
|
American
Hophornbeam
|
Ostrya virginiana
|
Musclewood
|
Carpinus caroliniana
|
Gilled
Polypore
|
Lenzites betulina
|
Christmas
Fern
|
Polystichum acrostichoides
|
Creek
ChubH
|
Semotilus atromaculatus
|
Round-lobed
Hepatica
|
Anemone americana
|
Planthopper
|
Hemiptera:
Flatidae
|
White-throated
Sparrow
|
Zonotrichia albicollis
|
Red-bellied
Woodpecker
|
Melanerpes carolinus
|
