Announcements of interest to Ramblers:
Pie day!!! Please come!!!
Sandy Creek
Nature Center 40th Anniversary Celebration
Sunday,
September 29, 2013; 3PM to 5PM
Trail walk with Dan Williams!
Sandy Creek
Nature Center
Tuesday,
October 1, 2013; 9:00AM
Photos of
today's ramble are courtesy of Don Hunter (the complete set can be found here.)
Today's
Ramble began with Catherine Chastain reading a selection from a wonderfully
illustrated book, Middlewood
Journal: Drawing Inspiration from Nature
by Helen Scott Correll, p. 78:
I can tell summer
is losing its grip. It’s interesting to
note that I understand more every year that the seasons, which I used to
consider fairly distinct, are really quite blurred. Cat brier and Virginia creeper leaves begin
turning red as early as July: fuzzy spring-like oak leaves sprout until
frost. During this morning’s ramble I
saw the first “fall” silvery aster bloom for the year, and the grass-leaved and
golden asters, which have been blooming for a couple weeks. Thoroughworts (upland, round-leaved, and
hyssop-leaved) are in bloom, but fading.
Tall goldenrods already brighten the woodland edges. Joe Pye weed and pale indian plantain are in
full bloom down by Meetinghouse Creek.
While I drew, fall
field crickets trilled in the field behind me, and a white-breasted nuthatch’s
loud and nasal ank ank! ank ank! ank ank! gave away his position as he walked
head-first down the trunk of an oak looking for insects. I remember the bird’s name and differentiate
him from the brown creeper, who also hops on tree trunks, by thinking what a
“nut” the nuthatch is to hop head-first straight down the tree. The way a brown creeper does it, starting at
the bottom of the tree and spiraling up the trunk, seems so much easier. The name nuthatch actually comes from the
bird’s habit of wedging nuts into cracks in a tree bark, then whacking at it
with his sharp bill to “hatch” the nut from its shell.
A pileated
woodpecker screamed several times close by.
A breeze kicked up and stirred the leaves, eventually becoming a steadying
cooling wind that persuaded me to stay a while after journaling, just to enjoy
it.
We then
walked through the shade garden to the road, down the road to the power line
and then to the river. Today's theme was "vines," but we saw many
other interesting things, both flora and fauna.
 |
| Land Planarian (Bipalium kewense) on human finger |
Our first
find (on the sidewalk in the shade garden) was a real surprise -- a land
planarian (Bipalium kewense) that was
attacking an earthworm.
Planarians
are a type of free-living flatworm (Phylum Platyhelminthes). Flatworms are weird
by human standards. They have no circulatory system and a single opening into
the digestive tract (a mouth but no separate anus). The mouth isn't located on
the head, but instead somewhere in the middle of the body, and also serves as
the anus. The majority of flatworms are parasitic and cause many severe human diseases,
such as schistosomiasis. (Tapeworms and liver flukes are other examples of flatworm
parasites that afflict humans.) But the free-living flatworms are not parasitic
and the land planarian we saw this morning is actually a predator, feeding on
earthworms and other soil-dwelling animals. In fact we first thought we were
seeing a "sick" earthworm. It's long, skinny tail turned out to be
the land planarian attached to the posterior end of the worm. This species has
no common name (Bipalium kewense) and was first discovered in Kew Gardens in
England. It seems to have originated in SE Asia and has spread worldwide,
probably via the horticultural trade.
The first
vine we found ascending the arbor at the edge of the road. Identification was
difficult because we couldn't see the leaves clearly, but the consensus was for
Wisteria frutescens, our native
Wisteria. (The Wisteria that grows on the arbor next to the parking lot is not
a native, it is Chinese Wisteria and has to be frequently pruned to prevent it
from escaping into the adjacent trees.
Vines have
several methods of climbing up, on and over nearby plants. They can simply grow
over other plants; they can get support by twining around the other plant stems;
or they can use specialized structures like aerial roots or tendrils to hang on
to other plants
 |
| Aerial root of Poison Ivy |
The native
wisteria growing on the arbor at the road edge is a nice example of twining.
There are two plants growing up it, one is right-handed and the other
left-handed. It seems odd to be talking about handedness in an organism that
lacks hands, but a vine can twine in two directions. As it grows up a support
it can encircle it to the right or left. Around the world about 90% of vine species
are right-handed. A few are ambidextrous and the rest are lefties. The
interesting question is why? Does it matter which way a vine curls around its
support? There doesn't seem to be any obvious reason, but then why are most
humans right handed?
The next
vine we encountered, Poison Ivy (Toxicodendron
radicans), is a wonderful example of a vine that climbs by means of aerial
rootlets.
 |
| Ilicium parviflorum fruit |
As we walked
down the road we noted the star shaped fruits and licorice odor of the Yellow
Anisetree (Ilicium parviflorum) and the enormous, bipinnate leaves of Hercules'
Club (Aralia spinosa).
 |
| Fruits of Virgin's Bower |
Near the
wooden fence by the road we found Virgin's Bower (Clematis virginiana) that had finished blooming but the fruits were
present, although they looked a bit bedraggled after yesterdays rain. This is a
native species. We have previously seen Yam-leaf Clematis (C. terniflora) in the garden, an invasive look-alike. Virgin's Bower usually has 3 ovate, toothed
leaflets whereas the other species usually has 5 untoothed leaflets.
This is the
season when orb weaving spiders become obvious. Their webs always seem to be
about face high and strung across the trails in the garden. It's always
annoying to walk into one, but did you ever stop to wonder how a little spider
got that elaborate web stretched from side to side in a trail?
A web begins
with the construction of a framework. This silk is not sticky and its function
is to provide a scaffolding on which the sticky capture threads can be hung.
The framework begins with a spider climbing to suitable height, elevating its
abdomen and releasing a strand of silk with a sticky end. Silk is very light
and can be carried away by the gentlest of breezes. Eventually the free end is
caught in nearby vegetation and the spider pulls it taut. The spider then anchors
her end of this strand and attaches another strand of silk to its resting place
and proceeds to walk across the first line, producing a second silk strand as
she goes. When she gets to the end of the first strand she anchors the second
silk line and then walks back to the center of the second line. Then she
attaches a third line to the middle of the second line and drops to the ground,
spinning out the third line as she descends. Upon reaching the ground she reels
in the third line, which pulls down on the center of the second line and
creates a triangular frame which is the beginning of the framework for the
capture web.
We saw three
different orb weaver spiders today.
 | |
| Yellow Garden Spider |
Yellow
Garden Spider (Argiope aurantia) with
a nearby egg case.
 | |
| Yellow Garden Spider egg case |
 |
| Spinyback Orbweaver |
Spinyback
Orbweaver (Gasteracantha cancriformis).
This spider spins a web with the characteristic thread pattern: thin, fuzzy,
thin, . . .
 |
| Spined Micrathena |
Spined
Micrathena (Micrathena gracilis)
One of the
very tall grasses that attracted our attention was Silver Plume Grass (Erianthus alopecuroides). We saw several
scattered specimens, each around 9 feet tall.
 |
| Waterpepper |
 | |
| Smartweed |
In the damp
areas of the power line we saw dense stands of two kinds of Smartweeds (family
Polygonaceae): Waterpepper (Persicaria
hydropiper) with tiny white flowers and a Smartweed (Polygonum sp.) with tiny pink flowers. Neither of these plants is
on our list for the garden so you might want to add them. Several clumps of Rushes
were also seen growing with the smartweeds. These are difficult to identify so
I'm not going to attempt to give a name to them. You can distinguish among rushes,
sedges and grasses by using the following ditty:
Sedges have edges.
Rushes are round.
Grasses have joints,
All the way to the ground.
 | |
| Dodder flowers |
We found the unusual parasitic plant, Dodder (Cuscuta sp.), and it was flowering! Only a short segment of
its orange stem was visible. Dodder twines around the host plant and sinks
root-like structures, called haustoria, into the vascular system of its host.
It's the vampire of the plant world. I have never seen Dodder in the Botanical
Garden before and it is not on the plant list -- another one we need to add.
 |
| Small White Morning-glory |
Also in
bloom was Small White Morning-glory (Ipomea
lacunosa), another plant that is missing from our list. Look carefully at
Dan's photo of this plant and you can determine the direction of its twining.
Other vines growing in or near the power line right of way:
 | |
| Large Grape vines |
 | |
| Climbing Hempweed |
 | |
| Bur Cucumber flower |
Green Briars
(Smilax sp.): several species are
found in the garden natural areas; today we saw S. smallii. Most Smilax
species use tendrils for support. Each leaf has two tendrils that arise from
the petiole near its attachment to the main stem. When the tendrils come in
contact with a support they coil around it and ultimately harden. If you have
ever tried to remove a Green briar from another plant you know how tenacious
their grip can be.
 | |
| Yellow Crownbeard |
Camphorweed
(Heterotheca latifolia)
Goldenrod (Solidago sp.)
Yellow
Crownbeard (Verbesina occidentalis)
Ironweed (Vernonia gigantea)
 | |
| Tiger Moth caterpillar |
On the way
back we discovered a slug crossing the road and stopped to examine it. Slugs
are basically snails without shells, but they still retain a vestige of the
mantle, the organ that, in snails, secretes the shell.
Then we
retired as usual for conversation and snacks at Donderos'.
Dale
