Ramble Report September 28, 2023

 Leader
for today’s Ramble:
Kaitlin Swiantek and Catherine Chastain

Authors of today’s Ramble report: Linda and Don. Comments, edits, and suggestions for the report can be
sent to Linda at Lchafin (at) uga.edu.

Insect and fungi identifications: Don Hunter, Heather Larkin, Bill Sheehan

Link to Don’s Facebook
album for this Ramble.
All the photos that
appear in this report, unless otherwise credited, were taken by Don Hunter.
Photos may be enlarged by clicking them with a mouse or tapping on your screen.

Number
of Ramblers today:
35

Today’s emphasis: Pollination of native plants
and cultivars

Catherine
invited Kaitlin Swiantek, a grad student in horticulture at UGA, to speak to us
about her project and to walk with us through the International, Heritage and
Flower Gardens, sharing her observations about pollination issues,
including selection of insects capable of pollination based on both flower
structure and insect anatomy, among other things. She is studying several
species of Mountain Mint in the genus Pycnanthemum for their commercial potential for use in home and business landscaping as a way to support 
pollinators. Currently, there are only a few species available on the market: Pycnanthemum
muticum
, P. verticillatum, and P. virginianum.

Left to right: Pycnanthemum
muticum
, P. verticillatum, and P. virginianum
photo credits: Don Hunter, Kerry Woods, Alan Cressler
 

Announcements/Interesting
Things to Note:

The
Botanical Garden’s Fall Native Plant Sale begins this Thursday! Here are the
days and hours that plants will be available: Thu-Sat,
Oct 5-7 and Thu-Sat, Oct 12-14. Thursdays and Fridays: 4-6pm. Saturdays:  9am-noon.
For a list of species available for sale, email Linda.

Roger
Nielsen was applauded for receiving a Sandy Star Award at the annual Sandy
Creek Nature Center members’ meeting in recognition for the work he
has done through the years at the nature center.

Roger
also announced that recorded interviews with founders, past
staff, and significant contributors to the Nature Center are archived at UGA’s
Hargrett Special Collections Library and can be heard here. They
can also be heard on the Nature Center website here.

Terry
mentioned that Margaret Renkl, author of “Late Migrations” (2019) and “The
Comfort of Crows, A Backyard Year” (2023) will be speaking at the Athens-Clarke
County Library, October 16th, at 7:00pm

Gary reported that today, September 28, is “Good Neighbor
Day,” designated  by Jimmy Carter during his presidency. Coincidentally, Carter’s
99th birthday is this Sunday, October 1. To celebrate his birthday,
Creature Comforts is releasing a new beer, Beautiful Mosaic, an IPA named for a
remark made by Carter: “We have become not a melting pot but a beautiful
mosaic. Different people, different beliefs, different yearnings, different
hopes, different dreams.”

Reading:
Catherine read from “Thirteen
Moons on Turtles’ Backs, a Native American Year of Moons,” written by Joseph
Bruchac and Jonathon London, and illustrated by Thomas Locker.

Moon of Falling Leaves

Long ago, the trees were told

they must stay awake

seven days and nights,

but only the cedar,

the pine and the spruce

stayed awake until

the seventh night.

The reward they were given

was to always be green,

while all the other trees

must shed their leaves.

So, each autumn, the leaves

of the sleeping trees fall.

They cover the floor

of our woodlands with colors

as bright as the flowers

that come with the spring.

The leaves return the strength

of one more year’s growth

to the earth.

This journey

the leaves are taking


is part of that great circle


which holds us all close to the earth.

Show
and Tell:
A rambler brought a twig of Yaupon Holly with leaves that appeared diseased, wondering if
the cause is a pathogen or an insect. No one knew that answer.
Shown this photo later in the week, rambler and
plant pathologist Elizabeth Little had this to say: “I cannot say positively the cause without
more info. Possibly herbicide (chemical) uptake but does not look typical of glyphosate
drift damage…Anther possibility is eryophyid mites (my best guess) or another
tiny sucking insect. The mites feed in growing buds causing growth abnormalities. They are a sporadic problem and are not harming the plant. (Please no insecticide! Would
not work on this type of insect anyway, and causes more harm than good, and may not be the cause). Does not appear to be disease. Does not look viral.
There are no known significant disease or insect problems on Yaupon Holly. Plant
should be fine. See how it buds out in the spring.”


Today’s
Route:
We headed down to the Flower
Bridge, making our way through the China and Asia Sections to the Threatened and
Endangered Plant garden. From there, we passed through the Physic Garden and
Heritage Garden, and down the steps into the Flower Garden. From there we took
the Purple Trail/Flower Garden Connector trail to the Purple Trail, which we
took back up the Visitor Center.

OBSERVATIONS:

Bumblebee visiting a flower of
Blue Salvia.

On the Flower Bridge, Kaitlin focused on the Blue Salvia
in the planters, reporting that, in her study gardens, she sees carpenter
bees mostly nectar robbing since they are too large to enter many flowers. On
the other hand, bumblebees are generally small enough that they can access the
nectar directly by crawling inside the flower, thereby pollinating the flowers.

Left, Camellia flower with a single whorl of petals and right, a “doubled” flower with 3 or 4 whorls

Kaitlin
also commented on the problem of developing cultivars with showier flowers. An
example is the creation of “doubles” with twice or more of the natural number
of petals. For example, a wild Camellia flower has five petals in a single whorl, but a “doubled” Camellia has many whorls, each with many petals. The changes in flower anatomy result in sacrificing
reproductive features, such as stamens that normally produce pollen, or pistils which
receive and transmit pollen to the flower’s ovules. Both stamens and pistils can be induced to change into petals. Even nectar-producing structures
may be sacrificed to create more or larger petals. These extra-showy flowers
may briefly attract pollinators but the insects may learn that there’s nothing
to be found in these flowers and ignore them. And – a double-whammy for wildlife
– these flowers will not produce seeds. “Doubling” is now usually achieved by manipulating the genes that affect petal, stamen, and pistil formation. Before the era of genetic manipulation, nurserymen watched for natural mutations among their plants and propagated those they found desirable, with the same impact on pollinators.

Ovate Catchfly is flourishing in the Threatened
and Endangered Species section of the International Garden. This species is
rare throughout its range (Georgia, north to Virginia and west to Arkansas and
Mississippi) and is considered imperiled in Georgia. There is a small wild
population located in Athens in Ben Burton Park.
Its flowers have five white
petals that are about ½ inch long, each deeply divided into eight
segments.

Linda picked up a small branch in
the T&E section to use as a “Joro stick” – Bill realized that the stick had
already been put to a much more interesting use.

Covered with Brown-toothed Crust fungi,
the stick is home to a large number of galls created by an as yet unnamed midge
whose larvae eat the fungi.

Close-up of a dissected gall –
the hollow portion was occupied by a larval midge, now emerged. Last time we
saw these galls, in May, Bill took some home and raised the midges in
captivity. Photos of the midges can be seen here (scroll down).

Cone-like
inflorescence on the Hops vines growing on the Physic Garden arbor.

Golden-yellow glands are
found at the base of the bracts that comprise female Hop “cones.”
The glands are the source of the
compounds that produce “hoppy” flavors in beer. These compounds also
act as a preservative and promote a good head on a glass of beer.
Photo by Jan Coyne

Giant
Swallowtail caterpillar consuming the last of the leaves on Northern
Prickly-ash

Two weeks ago, Ramblers examined the
Northern Prickly-ash shrub in the Physic Garden and watched as Giant Swallowtail caterpillars
consumed the foliage on the tree. Today, we saw that the defoliation was nearly
complete and that the caterpillars have resorted to eating the thin, reddish-brown
bark on the twigs. We found two caterpillars remaining on nearby vegetation. Heather
said she has been visiting the tree every three days since our last visit here
and that she witnessed the transformation to pupae that dropped from the tree
and made their way into the duff surrounding shrubs.

Twigs scraped of bark by Giant
Swallowtail caterpillars.
Narrow-leaf Sunflower planted in
front of Longleaf Pines at the gazebo in the Heritage Garden

Ramblers asked the difference
between Narrow-leaf and Appalachian Sunflowers, and Linda pointed out the
narrow, single-veined leaves of the former and described the wider, oval leaves
of the latter. Both species’ leaves are very rough and sandpapery to the touch.
Narrow-leaf occurs throughout Georgia, Appalachian mostly in the mountains with
some populations in the upper Piedmont. Someone else asked about the range of Longleaf
Pines in Georgia. They are primarily found in the Coastal Plain, but there is a
“montane” form of the same species that occurs in the Ridge & Valley region
of northwest Georgia and south into the western Piedmont on Pine Mountain and nearby
ridges, as well as in adjacent northeastern Alabama.

Big
Bluestem grass is planted in the bed with Narrowleaf Sunflowers. Its seed heads have
3-5 spike-like branches forming a “turkey’s foot.” Don captured the unappreciated
beauty of grass flowers in this photo: the orange dangling anthers and
the purple bottle-brush stigmas. The anthers release their pollen into the
wind, while the plume-like stigmas gather it. Grasses are self-incompatible: only
pollen from a different plant will successfully pollinate a grass flower.

The
Heritage Garden sports an unusual variety of Okra this year: ‘Star-of-David,’ an
Israeli heirloom cultivar. The pods are larger and fatter than the pods on typical Okra. Someone spotted a
Squash Bug (below) on one of the okra plants.

The Indigo plants in the Heritage Garden’s Indigo bed are
now in fruit.

Indigo production was a major source of income during
colonial days in both Georgia and South Carolina. Producing indigo dye was a dangerous
and disgusting process relegated to enslaved laborers. The New Georgia
Encyclopia’s article
on Indigo described the process during
pre-Civil War years: “The noxious stench associated with processing indigo is
well documented. The fermenting liquid smelled so foul that processing
facilities were always located well away from dwellings. Long-term exposure to
the vapors given off by fermentation, oxygenation, and precipitation, as well
as the presence of disease-carrying insects, may explain why the life span for enslaved
workers involved with indigo processing has been reported to have been a mere
five to seven years.”
Indigo dye derived from plants has
been largely replaced by synthetic dyes but you can watch the process of
producing the dye by hand in modern Thailand here.

Entering the Flower Garden, we
were struck by the sweet smell of the Tea Olive in full flower. This particular
cultivar bears peach-colored flowers.
Ramblers gathered around Catherine
and Kaitlin in the middle of the Flower Garden where Kaitlin told us about her
efforts to document the diversity of pollinators seen on different plants.

Kaitlin
began her pollinator research by learning to identify the insect pollinators
that visited her Mountain-mint plants. At first, she used the broad categories
of insects (Bumble Bees,
Honey Bees, Small Bees, Carpenter Bees, Wasps, Flies,
Butterflies/Moths,
Other
insects) used by the Great Georgia/ Southeast Pollinator Census. Eventually,
she refined the identification process with the help of UGA entomologists, learning
to identify the insects to family or genus. Her observations sometimes required
captures, either directly with nets, or, for the smaller insects, the use of aspiration,
where the insect is sucked through a flexible tube into a collection bottle.

Kaitlin Swiatek

Catherine asked Kaitlin about underappreciated
pollinators – it’s not all about bees and butterflies. Kaitlin mentioned moths,
which we don’t normally see in the daylight hours, as well as flies,
particularly the little sweat bees and hover flies.

Clearwing Moth photographed in 2017
by Don in the Physic Garden
Gaura aka Bee-blossom in flower
Bee-blossom
flowers have long floral tubes filled with nectar that is accessed by insects
with long tongues such as bumblebees. Other species in this genus (Gaura
or Oenothera) that bloom at night are pollinated by moths.

Moth Mullein with its fancy
colorful stamens in the middle of the white flowers – the stamens’ filaments
are covered with purple bristles and the anthers are orange.
Linda was surprised to discover a
Tamarisk shrub in the Flower Garden. This globally invasive plant has degraded
riparian zones throughout the American southwest and other arid areas globally,
where it “displaces native plants, drastically alters habitat and food webs for
animals, depletes water sources, and increases erosion, flood damage, soil
salinity, and fire potential.”
Winterberry, a native holly species,
in fruit
Although its native habitat is wetlands, it appears to thrive in
upland gardens. Its long-lasting fruits provide birds with late winter food.

Obedient
Plant, a member of the Mint family, is another native wetland species that
makes an excellent garden plant. Its flowers are pollinated primarily by bumblebees but are also visited by butterflies and hummingbirds.

Foxgloves, native to Europe and western Asia, are popular garden
plants with their large, purple and white flowers in tall, erect spikes.The interior of their flowers is conspicuously dotted with nectar guides.

We returned to the Visitor Center
via the Purple Trail and were again struck by the number of downed and dead trees,
mostly Northern Red Oaks. Some were recently fallen, some older, but most appeared
to have died in the past few years. Northern Reds are at the very southernmost
edge of their range in the Georgia Piedmont and seem to be falling victim to
the increased temperatures and severe storms predicted by climate change
researchers for our area. Even a cursory survey of the forest floor reveals
that these old Northern Reds are not being replaced with Northern Red seedlings and saplings. The
large herds of deer that now roam the Garden’s forests are largely to blame for
that, but research conducted at Whitehall Forest, UGA School of Forestry, suggests
that frequent heat waves also impact Northern Red Oak seedlings. The
researchers exposed seedlings to consecutive heat waves and found that
they have lower rates of photosynthesis both during and between the heat waves,
and thus have lower survival rates.

Victoria asked for a look at a
hickory tree so the ramble ended with a search for a trunk with conspicuously braided bark. 
A Mockernut Hickory was finally spotted near the top of the Purple Trail.

SUMMARY OF OBSERVED SPECIES:
Blue Salvia     Salvia sp.

Eastern Bumble Bee     Bombus
impatiens

Ovate Catchfly     Silene ovata

Brown-toothed Crust Fungus     Hydnoporia
olivacea

Hops     Humulus lupulus

Northern Prickly-ash, Northern Toothache-tree Zanthoxylum americanum

Eastern Giant Swallowtail (caterpillar)    
Papilio cresphontes

Narrow-leaf Sunflower     Helianthus
angustifolius

Longleaf Pine    Pinus palustris

Big Bluestem     Andropogon gerardii

Star-of-David Okra cultivar     Abelmoschus
esculentus

Squash Bug     Anasa tristis

Indigo    Indigofera tinctoria

Sweet Tea Olive     Osmanthus fragrans

White Gaura (Bee Blossom)     Gaura sp.

Moth Mullein    Verbascum blattaria  

Tamarisk cultivar ‘Pink Cascade’     Tamarix
ramosissima

Winterberry     Ilex verticillata

Obedient Plant     Physostegia
virginiana

Purple Foxglove     Digitalis purpurea

White Oak     Quercus alba

Possumhaw Holly     Ilex decidua

Horse Sugar     Symplocos tinctoria

Mockernut Hickory     Carya tomentosa