We
continued the Thursday curse with a temperature in the low 30s. One of the
drawbacks of Daylight Savings Time is that 8:30 is really 7:30 as far as sun
time goes. Nevertheless, fifteen ramblers showed to brave the chilly weather.
Today's
reading was the famous quotation from Baba Dioum, the Senegalese
conservationist: "In the end, we
will conserve only what we love, we will love only what we understand, and we
will understand only what we are taught."
Today's route:
From the
arbor through the Shade Garden onto the White Trail (WT) to the power line right-of-way
(ROW). Then up the ROW to the fence and left along the fence to the WT. Turn
right, through the gate, and follow the WT to the second intersection with the
Red Trail (RT). Follow the RT to the WT, then turn left on the WT and follow it
to the intersection with the Green Trail (GT). Take the GT back to our starting
point on the WT and then back to the Arbor.
Arbor through Shade Garden:
As
we made our way down the Shade Garden path, Emily stopped to point out
the new blossom
on the same Golden Ragwort she showed us two weeks ago. The "-wort"
suffix is an old English word that simply means "plant," and has no
relationship to the near homophone "wart." The ragworts, of which
there are many species, all used to be encompassed in the genus Senecio. But recent analyses of the DNA
sequences showed that the Old World ragworts all more closely related than any
of them were to the New World species. Since our classification is supposed to
reflect evolutionary relationships it became necessary to provide the New World
ragworts with a different genus name, Packera,
much to the irritation of New World plant lovers who had been happily calling
them Senecio for many generations.
You will still see garden signage with the old name.
Golden Ragwort |
The
ragworts are also known as "groundsels" and M. Grieve, at Botanical.com, A Modern Herbal, has this
to say about the origin of the name:
The name Groundsel is of old origin, being derived
from the Anglo-Saxon groundeswelge, meaning literally, 'ground
swallower,' referring to the rapid way the weed spreads. In Scotland and the
north of England it is still in some localities called Grundy Swallow - only a
slight corruption of the old form of the word - and is also there called Ground
Glutton. In Norfolk it is often called Simson or Sention, which has by some
been considered an abbreviation of 'Ascension Plant.' It seems more probable
that 'Sention' is a corruption of the Latin, Senecio, derived from Senex
(an old man), in reference to its downy head of seeds; 'the flower of this herb hath white hair and when
the wind bloweth it away, then it appeareth like a bald-headed man.'
The
Golden Ragwort has certainly spread far and wide in the Dunson garden and is
fully consistent with the English name groundsel.
Chatahoochie Trillium |
Barbara
asked: "If the Trilliums are hybridizing does that mean they are not distinct
species?"
Species
concepts still provoke a lot of vigorous discussion among biologists. Botanists
and zoologists also differ in how they apply species concepts to the organisms
they study. Perhaps the most widely used definition is that species are "reproductively
isolated" populations in nature. This means that, in natural situations,
plants or animals that do not interbreed should be considered separate species,
even if they can interbreed when placed together in an unnatural environment,
or artificially hybridized, as in a garden or a zoo.
White Trail to Powerline ROW
In
the open, disturbed area at the intersection of the White Trail and the ROW we discovered many wildflowers in bloom. Some are
native, others naturalized. Naturalized is a term applied to a non-native plant
that has become established in an area where it does not naturally occur. Established
means that the plant population reproduces sufficiently to maintain itself in
that area.
Small Bluet |
Quaker Ladies |
Field Pansy |
White Dooryard Violet |
The
non-natives seen are two plants in the mint family and one in the mustard
family. The two mints are sometimes confused, but closer examination and
side-by-side comparison will reveal the obvious differences.
Hen Bit |
Purple Dead Nettle |
Mustard
family plants are also called crucifers, which means, literally, "cross
bearer." This refers to the flowers, which have four petals arranged in a
"+", or cross shape. We found a tiny cruciferous plant, Hoary
Bittercress, with a few tiny flowers and several slender, elongate seed pods.
This type of seed pod is also characteristic of the mustard family. When ripe
they will explode on touch, hurling the seeds considerable distances.
Power line ROW to gate:
Green and Gold |
Dixie Reindeer Lichen |
Serviceberry or Bradford Pear? |
White/Red/White Trail:
In
the woods we saw no more wildflowers blooming but encountered several
interesting trees, shrubs and even animals.
A
Red-headed Woodpecker was sighted. It is nice to see this species in the Garden
again. There was once a large number of them nesting in the Beaver pond, but as
the dead trees in the pond decayed and disappeared the Red-headed Woodpeckers
did so also.
Look at the wings on that Elm! |
Black Jelly Oyster Mushroom |
The
Beech trees still have not dropped their leaves and the long, pointed buds
don't show any signs of opening.
Blueberry blossoms |
Don called our attention to a Witches Broom on a small Hophornbeam. This strange growth is found on
several species of tree and is by a fungal infection
(or by the activity of insects
that might introduce a pathogen into the tree). The result is the rapid
proliferation of short, weak stems in one area of the tree. The dense, shrubby
growth resembles a bundle of twigs used to make a broom, thus the name.
Witch's Broom on Hophornbeam |
But
why does the tree respond in this peculiar way? Just under the bark of a tree
are living tissues that can produce new branches. They are held in check by the
production of a plant hormone called auxin, which is produced by the growing
tips of each tree branch. When a branch is damaged, or cut off, the supply of
auxin is interrupted and the inhibition of the buds further down the branch is
released. There is another plant hormone, called cytokinin, that stimulates
cell division. Cytokinin can activate cell growth, even when auxin is present.
The Witch's Broom is caused by the production of excess cytokinin by the
infectious agent. This releases the surrounding tissue from auxin inhibition
and rapid, uncoordinated growth ensues
Betsy Beetle |
On
the way back we stopped to briefly admire a small Buckeye, its leaves freshly emerged from the
buds and just barely out of the ground. Buckeyes seem to be the first of the deciduous trees to break bud in the spring. And the first to shed their leaves in the fall. Is there a correlation?
Summary of Observed Species:
Common Name
|
Scientific name
|
Comment
|
Golden Ragwort
|
Packera aurea
|
blooming
|
Chattahoochee Trillium or
Chattahoochee Wake Robin
|
Trillium decipiens
|
blooming
|
Small Bluet
|
Hedyotis pusilla?
|
blooming
|
Quaker Ladies
|
Hedyotis caerula
|
blooming
|
Field Pansy
|
Viola rafinesquii
|
blooming
|
Dooryard Violet or
Confederate Violet |
Viola sororia
|
blooming
|
Hoary Wintercress
|
Cardamine hirsuta
|
blooming
|
Henbit
|
Lamium amplexicaule
|
blooming
|
Purple Deadnettle
|
Lamium purpureum
|
blooming
|
Spiderwort
|
Tradescantia sp.
|
blooming
|
Green and Gold
|
Chrysogonum virginianum
|
blooming
|
Dixie Reindeer Lichen
|
Cladina subtenuis
|
blooming
|
Pixie Cup Lichens
|
Cladonia sp.
|
blooming
|
Service Berry
|
Amelanchier Canadensis
|
blooming
|
Winged Elm
|
Ulmus alata
|
blooming
|
Black Jelly Oyster
Mushroom
|
Resupinatus applicatus
|
on Sweet Gum
|
Sweetgum
|
Liquidambar styraciflua
|
|
Blueberry
|
Vaccinium sp.
|
blooming
|
American Beech
|
Fagus grandifolia
|
|
Hop Hornbeam
|
Ostrya virginiana
|
with Witches Broom
|
Patent Leather Beetle
|
Odontotaenius disjunctus
|
|
Buckeye
|
Aesculus sp.
|
|
Red-headed Woodpecker
|
Melanerpes erythrocephalus
|