Today's Ramble was lead
by guest leader Lauren Muller and Linda Chafin.
Here's the link to Don's Facebook album for today's Ramble.
(All the photos in this post are compliments of Don.)
Today's post was written
by Don Hunter and Dale Hoyt.
Twenty-four Ramblers turned
out today.
Introduction to our guest leader: Lauren Muller graduated last year from UGA
with a degree in Horticulture. She is currently a graduate student in the Horticulture
department working with Dr. Jim Affolter, working on milkweed propagation.
Lauren is also involved with the Prairie restoration effort in the power line
right-of-way. She agreed to tell us about that project and her own research on milkweed
propagation.
Today's reading: is from The
World of Northern Evergreens, 2nd ed., 2011, Comstock Publ.; by E. C.
Pielou.
Outdoor people have a
wide spectrum of interests. Specialists tend to
specialize in 'interesting' items: a birder
is more likely to concentrate on owls than on starlings, and the average plant-hunter finds orchids more fascinating
than crabgrass. Because of this preoccupation with the hard-to-find, the beautiful, and the unusual, most of the
commonest objects in nature are apt to be ignored. They are simply there, part
of the background. But to assume that because a thing is common it is therefore uninteresting is a mistake.
For most outdoor people
the fact that they will encounter rank upon rank of coniferous trees in
excursion after excursion in the future neither pleases nor displeases them.
They don't even think about it. If there are innumerable coniferous trees in your
future, why not take advantage of the
fact, look at the trees more closely, and learn something about them? Knowledge
cannot fail to bring interest and appreciation.
Learning to identify the
different species of coniferous trees is only a beginning. Once you know the
trees, many things can be observed if you know what to look for. There is however, a world of difference between
seeing and interpreting. The ability to interpret is the hallmark of the true
naturalist and developing that ability is one of the pleasures of being a
naturalist. The well-informed
naturalist understands and enjoys a thousand things that the uninformed one
doesn't even notice; and the more people who understand and enjoy the woods,
the more there will be to protect them.
Today's route: We hustled over to the power line right-of-way
where Lauren told us about the prairie restoration project she is involved in.
From there she showed us the propagation facilities at the Mimsie Lanier Center
for Native Plant Conservation. Then we proceeded to the upper reaches of the
power line ROW to see what was currently blooming. When it got hot we retreated
back to the parking lot and Donderos' Kitchen.
Test plot at the Power Line ROW:
Lauren gave us an overview of the prairie
restoration project. The phase currently in progress is to determine the best
way to eliminate the non-native grasses from the future prairie. The project is
funded by an Institute of Museum and Library Services grant.
[DH; Note: The
following account is my paraphrase of Lauren's presentation. Any errors or
misinterpretation are mine, not Lauren's.]
 |
| Ramblers look over the test plot while listening to Lauren |
This future "Prairie
on the Hill" is presently covered by a lawn of non-native grasses between
the White trail and Lanier Center access road. The first problem in converting
this area to a prairie is to determine the best way to 1) get rid of the existing
grasses and 2) establish the appropriate native species of herbs and grasses. Last
March a test area was sprayed with the herbicide glyphosate (Roundup) to kill
the grasses (mostly Fescue, Bermuda grass and Crabgrass). In May Crabgrass was
sprayed a second time. In the meantime Heather Alley, Conservation Botanist at
the Mimsie Lanier Center for Native Plant Studies, has been growing
"plugs" of native grasses and herbs to plant in the study plot this
coming October.
The purpose of the test
plot is to determine the most effective way to treat the area before planting
it. Would simply planting the new material directly into the existing duff of
dead grasses work? Or should the area be tilled first? Or would it be best to
cover the area with black plastic or landscaping fabric and cut holes to insert
the new plants? To decide the best strategy the test plot will be subdivided
and each sub-plot subjected to one of the several different treatments. The
best method of converting the entire lawn into a native Piedmont prairie will
be determined by comparing the results from these different plots.
Questions for Lauren:
Why does fescue (and the other non-native grasses) out-compete the
native grasses?
1.
The three grasses grow vigorously and spread via
rhizomes and stolons.
2.
They have a fast life cycle, rapidly growing from
seed to mature, sexually reproducing plant.
3.
They create dense mats that exclude other plants.
4.
Fescue is evergreen so it can photosynthesize and
grow during winter.
How long does glyphosate persist in the environment after it's applied?
Glyphosate
will completely degrade over a period of several weeks. It's also really a fairly benign herbicide.
Lauren's research:
She is investigating the most efficient method for propagating and
establishing Butterfly weed, the common orange flowered milkweed native to our
area. She is using raised beds at the Atlanta Botanical Garden in Gainesville to
test different methods of propagation there. She selected Butterfly weed
because, of the species native to Georgia, its seed is the most readily
available.
She will test her methods at two sites, one
here at the State Botanical Garden (further up the hill in the more established
areas of the prairie) and one at Panola Mountain. The Panola Mountain site has
a well established prairie which has been the subject of many prescribed burns
and has been planted with an assortment of native plants.
Plantings will
start this fall and continue at different times next year. Her seedling plants are coming along nicely
and she said volunteers to help in
planting the plugs this fall would be appreciated.
She will
compare establishment of milkweed in three different treatments: 1) inter-planting
milkweed among existing vegetation, 2) mowing before planting (this eliminates above
ground competion, but leaves the root systems intact) or 3) spraying the
existing vegetation with glyphosate to eliminate both above and below ground competition.
Establishment success will be determined over the next year by measuring the general survival of the plants and using
various growth metrics; e.g., height, flowering and general health.
Lauren has also
grown about eleven different milkweed species, including Asclepias obovata, A. verticillata,
A. tuberosa, A. incarnata, A. exaltata and A. michauxuii,
in raised beds at the Gainesville Conservation Nursery. Her seed sources are from populations within a 50 mile radius so they are
adapted to our local climatic/ecological conditions. She wants to grow these
local eco-types to get more seed for the SBGG prairie restoration project, as
well as to see how well these species will grow.
Milkweed biology:
How are milkweeds pollinated?
The structure that contains pollen and is carried from one flower to
another is called the pollinium. It
is shaped like a wishbone. Where the two parts join together is a sticky gland
called the corpusculum. Two arms,
called translators, extend from the
corpusculum and at their ends each carries a sack of pollen grains.
Collectively the bags of pollen are called pollinia.
To clarify, if the pollinium is a wishbone, the ends you and your opponent grab
when making a wish are the pollinia, the two bones that are connected at the
top are the translators and the place where they are attached together is the
corpusculum.
When an insect visits a milkweed flower if its leg slips down into a
slit where the pollinium is the sticky corpusculum adheres to it. When the
insect pulls free the pollinium is pulled out of the flower. Now the pollinator
has the little wishbone of two pollen sacks glued to its leg. When it flies to
the next flower (assume that it on a different plant) it will pollinate it only
if it steps into a slit where the pollinia can be scraped off. The position of
the pollinia has to change to accomplish this. After the pollinium gets glued
to the leg it takes a couple of minutes for them to swing to the new position.
This repositioning of the pollinia is done by the translators.
Complicated, isn't it!
If you examine a milkweed during the fruiting period you will see very
few pods (fruit), indicating that very few of the flowers are successfully
pollinated. But all it takes is one flower to be pollinated and the resulting
fruit will contain hundreds of seeds, each one formed when one of the pollen
grains in the pollinium reached one of the ovules in the flowers ovary.
After pollination do milkweeds face any other
problems?
Other dangers threaten maturation of the seed. Milkweed bugs penetrate
the fruits with their piercing-sucking mouthparts and drain the seeds of all
their nutrients. Milkweed beetle adults and larvae feed on the leaves,
depriving the developing seeds of the energy needed to mature. Oleander aphids
(yellow or orange in color), another non-native species, attack the milkweed
stems and suck the nutrients out of the plant, making more aphids rather than
milkweed seeds.
With all these problems how can you establish a
population of milkweeds?
If the individual plants are dispersed and not concentrated in a dense
stand the risk of attack is diminished. Other plants, like dogbane, are
attractive to milkweed bugs and can "spread the load" if planted some
distance away.
Is milkweed a good nectar source?
Butterfly weed produces a lot of high quality nectar and attracts many potential
pollinators: bees, wasps, beetles, ants and butterflies. In addition to its
importance as a nectar source it, as well as other milkweed species, serves as
the larval host plant of the Monarch butterfly and its relatives. Monarchs lay
their eggs on milkweeds and the caterpillars cannot successfully feed on any
other plant. [DH: Some sources claim that Milkvines (Matelea sp. and Gonoloba
sp.) can support the growth of Monarch caterpillars while other sources state
that this is not the case.]
Mimsie Lanier Center for Native Plant Studies:
The IMSL grant is also funding work on the floodplain restoration. Heather
Alley, Conservation Horticulturalist is growing plugs of grasses for this
effort.
Lauren pointed out that some years in the past a large mulching device
was used in this area to eradicate Chinese privet. It churned up the land,
grinding up everything in its path. In subsequent years the privet reappeared, either
from the seed bank or from chopped up root pieces. These new plants were
controlled by applications of glyphosate. The occasional new sprouts are
controlled by spot spraying.
Lanier Center Gate:
[DH: In the fall of 2012 a flock of sheep were brought into this small
area of the flood plain to browse down the privet. They were released inside
the fence and corralled by a portable fence to keep them concentrated in the
desired area. After several days the flock moved on. Some anecdotal reports indicate
that some agricultural weeds were found in the grazed area, but determining
their source is a problem. Sheep are ruminants, which means that they chew
their cud. (As they graze the ingested plant material goes into the first
chamber of the stomach where it is mixed with fluids and digestive enzymes.
After some time this mass, now called "cud," is regurgitated and
chewed further. Then it is swallowed and passes into the other parts of the stomach
where it is further digested and the bulk of the fluid reabsorbed. The result
is tiny pellets that are defecated. The double chewing that occurs reduces the
likelihood of any seed surviving the transit through the gut. I've never heard
any more comments on the effectiveness or ineffectiveness of the sheep in
controlling the target plants in this area. I welcome comments – use the
comment box at the end of this post to start a discussion.]
At the Green houses:
 | |
| Ramblers view prairie plant propagation |
First greenhouse contained plants that Heather is growing for a future
native plant sale.
Second greenhouse contains plants that are designated for the prairie
grassland project. Included are, among
others: Eupatorium, bluestem grass, Purple
love grass, Mountian mint and Bee balm.
Heather has been growing these since the spring and they will be ready
to go out in the fall.
 | |
| Butterfly weed; will any of these produce fruit? |
We walked outside where some Butterfly weed is planted. Most of the
flowers have dropped and the presence of firm, upturned stems will indicate
that their flowers were pollinated and fruit will begin to form. Each flower
can potentially give rise to a single fruit, but each plant may have as many as
one hundred flowers, but only produce 1-3 fruits, if that many. Last year no
fruits were produced by this group of plants.
Linda's discussion about invasiveness:
Linda was asked about invasive plants and I hope I've captured the
essence of her reply. Rosemary mentioned that on the wildflower pilgrimage several
of the leaders referred to Rhododendron as invasive. Someone else said that they
heard that Live oaks were invasive in the coastal plain. Linda addressed the
latter. The coastal plain ecosystem was dominated by the Longleaf pine-wiregrass
association before the advent of European colonization. This ecosystem was
maintained by frequent, low intensity fires caused by frequent lightning
strikes. The Longleaf pine is fire adapted and can withstand such fires, but Live
oak saplings are killed by them. So as long as fire is frequent it prevents the
growth of fire-sensitive woody plants in the coastal plain. The pines are
adapted to a landscape where fire is common. In the absence of fire woody
plants can establish and their growth shades the understory, suppressing the
growth of young pines. With the advent of colonial agriculture fire was
suppressed setting the stage for the establishment of Live oak or other woody
plants. In addition the leaves of Live oak are thick and leathery. When they
fall they have curled edges making them like tiny shallow cups. These mini-cups
can hold water and this impedes the spread of fire. Thus, when the oaks become
established they can suppress the spread or intensity of fires. As Sue pointed
out, this is an ecological process called succession. [DH; my two bits: We need
to be careful using terms that are emotionally laden when we label natural
processes. This is a good example. On the one hand a plant can be portrayed as
"invading" the domain of another plant and displacing it. On the
other they can be viewed as simply being part of a natural process
(succession). We should recognize that the value attached to a process is
really external to that process. Remember that the disappearance of the
Longleaf pine ecosystem was not due to the spread of Live oak. It was because
humans harvested the Longleaf and replaced them with faster growing species, cities
and farms.]
Upper Powerline ROW:
All the plants we noticed are listed at the end of the blog.
 | |
| Praying mantis egg case |
Praying mantis egg case:
Attached to a stem at the edge of the path someone spotted the egg case
of a Praying mantis. Last fall a female mantis finished eating her mate and
deposited her eggs in a group surrounded by a spongy mass that has the texture
of styrofoam packing peanuts. It is also covered with a secreted layer of a water
resistant substance, so her eggs pass the winter dry and insulated from the
weather. She then dies. About this time of year the eggs hatch and the babies,
looking like tiny versions of their mother, struggle out of the case and wander
off, looking for small insects to capture and eat. There will be 50 to 100
babies produced, depending on the size and health of their mother.
 | |
| Carolina Milkvine flowers |
 | |
| Carolina Milkvine fruit |
Carolina Milkvine:
In the prairie to the west of the path we discovered a Carolina Milkvine
with both flowers and a fruit. Milkvines are related to Milkweeds. Their shared
name comes from the fact that most species exude the same milky, latex containing,
fluid from cut stems or leaves. Carolina Milkvine has flowers that are entirely
dark maroon and a fruit that is spiny or warty. Another species of Milkvine in
found in our area, but we didn't see it today.
 | |
| Carolina Horse-Nettle; note the cluster of yellow anthers |
Carolina Horse-Nettle and buzz pollination:
The flower of this plant resembles that of a tomato plant, or, for that
matter, other members of the Nightshade family. It has long, yellow anthers
that closely surround the central pistil of the flower. In addition the anthers
open at the pointed end, instead of splitting open as in many other plants. The
pollen inside the anthers is dry and dust-like; many other insect-pollinated
plants have large, sticky pollen grains. These feature are seen in plants that
rely on pollinators that can perform "buzz" pollination, typically
bumblebees. In buzz pollination the bee grasps the flower and vibrates its
flight muscles without moving its wings. When it does this it emits a buzzing
sound that gives the process its name. That vibration is transmitted to the
flower and the pollen is shaken out of the anthers. So how does the dust-like
pollen get on the bee? When a bee flies through the air it acquires a charge of
static electricity and the dry, dust-like pollen is attracted to the hairy body
of the bee. Some of our important crops rely on buzz pollinating bees,
blueberries being one of them. In locations where blueberries are produced in
greenhouses growers find that more berries are produced if bee colonies are
placed inside the greenhouse. Not honeybee colonies – colonies of other types
of bees, because honeybees cannot buzz pollinate.
Other flowers seen:
 | |
| Wild Bergamot |
 | |
| Carolina Desert Chickory |
 | |
| Queen Annes' lace |
 | |
| Sensitive Brier |
 | |
| Wild Petunia |
SUMMARY
OF OBSERVED SPECIES:
|
Common Name
|
Scientific name
|
|
Power line ROW test plot
|
|
|
Crab
grass
|
Digitaria
sanquinalis
|
|
Tall
fescue
|
Festuca arundinacea
|
|
Bermuda
grass
|
Cynodon
dactylon
|
|
Mimsie Lanier Center
|
|
|
Butterfly
weed
|
Asclepias
tuberosa
|
|
Virginia
buttonweed
|
Diodia
virginiana
|
|
Elaine Nash Prairie
|
|
|
Carolina
desert chicory
|
Pyrrhopappus
carolinianus
|
|
Queen
Anne's lace
|
Daucus
carota
|
|
Sensitive
brier
|
Mimosa
microphylla
|
|
Mountain
mint
|
Pycnanthemum
incanum
|
|
Bee
balm
|
Monarda
fistulosa
|
|
Praying
mantis egg case
|
Insecta: Mantodea
|
|
Mockernut
hickory
|
Carya
tomentosa
|
|
Carolina
milkvine
|
Matelea
carolinensis
|
|
Carolina
horsenettle
|
Solanum
carolinense
|
|
Wild
petunia
|
Ruellia
caroliniensis
|
