Friday, September 16, 2016

Ramble Report September 15 2016



Today's Ramble was lead 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.) Don also put together an album of nifty photos he calls "Monroe County Lichen Foray Lagniappe." If you want to know what lagniappe means or look at more of Don's photos just visit this link.
Today's post was written by Dale Hoyt.

Attendees: 22

Announcements: 

There were quite a few announcements relevant to Ramblers today:

·        The Alhuda Islamic Center of Athens is inviting us for Eid dinner Sept. 18.
·        Anne Shenk's retirement gathering Sept. 27
·        Sandy Creek Nature Center's annual bird seed sale begins.
·        Barnes & Noble bookfair Oct. 7-9 benefiting the Garden's children education program.
·        Oct. 8 our own Gary Crider will teach a course in the Certificate in Native Plants program on how to identify and control exotic pest plants.
For details about these announcements visit this page.

Misc. links you'll enjoy:  

My friend, Dac Crossley, reminisces here about spiders he has known.

Today's reading:
Dale read the lyrics to Misalliance by Flanders and Swan; hear them sing the lyrics here. If you have trouble understanding the English accents you can find the written lyrics here.

Today's route: We've been having trouble getting to the floodplain power line right-of-way lately – we've run out of time the last two weeks. So today we hustled down the cement walkway to the access road without stopping. We walked down the road to the Passion vines on the fence and from there to the power line and down towards the river. We returned to the arbor via the White trail.

Gulf fritillary caterpillar; in some individuals the purple stripe is more pronounced.
Variegated fritillary caterpillar; beautiful red with white stripes.
The Variegated Fritillary challenge: We stopped at the Passion vines we've been watching disappear the past two weeks. Our challenge was to find caterpillars of the Variegated Fritillary (VF) with only a description of them to go on. By far the most numerous caterpillar was the Gulf Fritillary (GF). The VF caterpillar looks very similar to the GF, but has a red body color with white stripes that runs the length of the body. It was quite a challenge but the Ramblers were up to it and soon discovered two VF caterpillars. The adult VF butterfly is not as common as the GF and we didn't see one this morning. But if you come to the power line an hour or so later, when the sun is shining on all the flowers, you may see one or two nectaring and searching for uneaten Passion vines. While we were gazing on the remains of the Passion vines Avis stomped on one of the fruits to show another Rambler why they are called "Maypops." But that origin of the name is folk etymology. The real origin is an English corruption of the Indian word for the fruit: maracock, which means "rattle-fruit." When the gourd-like fruit is dried the seeds rattle within it.

More about insect metamorphosis.
The pupal stage of a butterfly is called a chrysalis or chrysalid (pl.: chrysalides or chrysalises). Strictly speaking, the chrysalis is the hard covering of the pupa which is inside the chrysalis, but, in general usage, it is often used to mean the pupa plus the shell.
It is in the chrysalis that the miracle of metamorphosis takes place. Within the body of the caterpillar, in addition to the customary organs (muscles, digestive tract, nervous system, etc.), there are tiny sacs of embryonic tissues called imaginal disks (ID) that will give rise to all the parts of the adult. (You can think of these as equivalent to embryonic stem cells.) During the formation of the chrysalis all the caterpillar tissues and organs, except the nervous system and the ID, undergo self destruction. The death of all these cells releases the substances that will fuel the growth of the ID to make the adult form.
Two hormones, ecdysone and juvenile hormone (JH), are involved in controlling the growth of the caterpillar through several molts and its transformation into the chrysalis and then the adult. In simple terms, pulses of ecdysone stimulate the molting process. What emerges from the molt is determined by the level of JH. When JH is high the growth of ID is inhibited and a caterpillar emerges from the molt. At the end of the last caterpillar molt the levels of JH begin to drop. The caterpillar stops eating, evacuates its hindgut and begins to wander. When it finds a suitable place to form a chrysalis it stops and after suspending itself begins to molt into the chrysalis stage. During the chrysalis stage the levels of JH continue to decline and the ID are no longer inhibited. The ID cells start to divide rapidly and they begin to form the adult structures. At the last molt the adult emerges from the chrysalis. 

Silver-spotted skipper

Silver-spotted skipper on Ironweed
Butterfly egg under the folded edge of American wisteria vine;
the egg is a little less than 1 mm in diameter.
A Silver-spotted skipper egg from another source for comparison with the one above.
from https://www.learner.org/jnorth/tm/monarch/egg_butterflies_gallery.html

Rosemary noticed that the American wisteria vine growing on the rail fence by the road had several leaves with a section of the edge folded over. I examined one and didn't find anything under the fold, but a second leaf had the empty shell of a butterfly egg under it. Several Ramblers were amazed at the intricacy of the structure; the egg is less than a millimeter in diameter. What kind of egg is it? One possibility is the Silver-spotted skipper. It's caterpillar feeds on wisteria and other legumes and this egg shell looks very similar to pictures on the internet. The Butterflies of North America indicates that the egg is: laid singly on the upperside of host leaves. . . .Young larvae live in a folded-over flap of a leaf. That matches what we saw.

Butterfly supplement

Cloudless sulphur; we've seen the caterpillar feeding on Maryland senna.

Gulf fritillary;underside of wings showing the silver spots.

Gulf fritillary; upper surface of wings.

Sleepy orange; the upper surface of the wings is orange;
they almost never rest with the wings open.
Don went back to the power line later in the morning when the sun was high enough to shine on the vegetation. Butterflies are sun lovers and aren't usually very active until it warms up. Direct sunlight is their friend. So Don was able to photograph several of the butterflies that we have only seen in the caterpillar stages.

Other insects.
Kissing bug; it can inflict a painful bite.
Catherine pointed out a small insect nimbly moving through the vegetation and I couldn't get a good look at it. It kept scrambling away so I grabbed it just as Catherine said: "I think it's an assassin bug." I immediately regretted my haste. I felt a sharp, painful burning sensation in my index finger. I finally got the critter in a box where I could get a good look at it. It was a true bug in the Assassin bug family, Reduviidae. More specifically, it was a Kissing bug, or Blood sucking conenose, Triatoma sp. Like all true bugs the assassin bugs have a needle-like mouth part which they stab into their victim, injecting a venom that paralyzes and digests at the same time. The digested liquid us sucked back up. If you've read Annie Dillard's Pilgrim at Tinker Creek you probably remember her stumbling upon a frog that had been reduced to hollow sack of skin by the bite of another kind of true bug. Kissing bugs normally feed on small mammals, ingesting small meals of blood, like vampire bats with tiny straws. In Latin America a related species transmits Chagas disease, a serious illness, but thankfully the North American species do not. The initial pain I felt was uncomfortable, but not as bad as a Fire ant or Honeybee sting; it was gone after 5 or 10 minutes.

It's hard to pick out the Chinese praying mantis from among the vegetation.

The sharp spines on the mantis front limbs insures a tight grasp on their prey.
Nearby a large female Chinese praying mantis was found on a Wingstem. This large predatory insects has raptorial front legs, meaning that they function like the legs of raptors: they seize and hold their prey, which consists of a variety of small and large insects. The mantis is an ambush predator. By hanging out in flowers it comes in contact with pollinators like bees, butterflies or moths. All it has to do is maneuver into striking distance and quickly grab its victim. Because the mantis is not selective in its food choice it is really not a good choice for pest control in the garden even though it is often promoted as a "natural" or "organic" solution. It can't tell a harmful from a beneficial insect – they're all food to the mantis. Which I hope will cause you to contemplate the meaning of "harmful" and "beneficial." Is the enemy of my enemy my friend?
During mating the female mantis is famous for eating the head of her mate who blithely continues doing his duty. (Insert warning against anthropomorphic comments.)

Common Ragweed showing foliage and inflorescence

Each tiny white bump is a pollen-spewing flower in this enlargement of a Ragweed inflorescence.
Ragweed is flowering right now and, fortunately, there is not a lot of it in this part of the garden. Ragweed flowers are very tiny and inconspicuous, so small that most people either don't notice them or don't recognize them as flowers. It is responsible for most of the allergies in late summer and fall. The plant is wind pollinated and the pollen grains are very small and dry, so they can be, and are, carried by the wind for hundreds of miles. Because the Ragweed flowers are so unnoticeable another plant, Goldenrod is often blamed for causing allergies in late summer or fall. This is because it, Goldenrod, begins to bloom at the same time as Ragweed. Noticing the correlation between Goldenrod flowering and the onset of allergy symptoms caused people to mistakenly blame it for causing the runny nose and itching eyes. But Goldenrods are insect pollinated and they have large, sticky pollen grains that are not transported by the wind. Goldenrod is blameless, the victim of confusing correlation with cause.

The Wingstems
Today was a review of how to identify the three species of Wingstems (genus Verbesina) that are all blooming in the garden right now. In this case the scientific names are more stable than the variety of common names. Remembering the combinations of flower color and leaf arrangement is the first step in identifying them. (Recognizing them comes later.) I'll use the common names from Linda's book in the summary below:

Yellow flowers:
   opposite leaves: V. occidentalis (Southern Crownbeard)
   alternate leaves: V. alternifolia (Wingstem)
White flowers
   alternate leaves: V. virginica (Frostweed)

Sunflowers
There are two sunflowers (genus Helianthus) blooming in the Garden right now. They are a little more difficult to identify than the wingstems, so Don made a special effort to take pictures of the crucial parts. I hope this helps.

Rough-leaf Sunflower:
   mostly opposite leaves
   Upper surface of leaves very rough
   Under surface of leaves with glands, not as rough as upper
   Base of leaf blade rounded
   Petioles longer (3/4 inch)
Woodland Sunflower
   leaves opposite to alternate
   Both surfaces of leaves very rough
   Base of leaf blade tapered
   Petioles short to none

Rough-leaf Sunflower
Note rounded base of leaf blade


Woodland Sunflower

Rough-lead Sunflower;
Note longer petioles

















Woodland Sunflower;
Note shorter petioles; tapered base of leaf blade















    
  
SUMMARY OF OBSERVED SPECIES:

Common Name
Scientific Name
Passionvine
Passiflora incarnata
Gulf fritillary
Agraulis vanillae
Variegated fritillary
Euptoieta claudia
American wisteria
Wisteria frutescens
Yellow crownbeard
Verbesina occidentalis
Tiger moth caterpillars
Subfamily Arctiinae
Bumblebee
Bombus sp.
Spittlebugs
Family Cercopidae
Chinese praying mantis
Tenodera sinensis
Wingstem
Verbesina alternifolia
Late flowering thoroughwort
Eupatorium serotinum
Sericea lespedeza
Lespedeza cuneata
Ticktrefoil
Desmodium sp.
Kissing bug
Reduviidae: Triatoma sp.
Leafy elephant's foot
Elephantopus carolinianus
Tall thistle
Cirsium altissimum
Common camphorweed
Heterotheca latifolia
Asian multicolor lady beetle
Harmonia axyridis
Rough-leaf sunflower
Helianthus strumosus
Woodland sunflower
Helianthus divaricatus
Eastern tiger swallowtail
Papiliop glaucus
Sleepy orange
Abaeis nicippe
Cloudless sulphur
Phoebis sennae
Tall ironweed
Vernonia gigantea
Silver-spotted skipper
Epargyreus clarus
Mild waterpepper
Persicaria hydropiperoides
Arrow-leaf tearthumb
Persicaria sagittata
Small white morning glory
Ipomoea lacunosa
Common ragweed
Ambrosia artemisiifolia
Carolina horsenettle
Solanum carolinense
Climbing hempweed
Mikania scandens
Virginia dayflower
Commelina virginica
White crownbeard
Verbesina virginica


3 comments:

  1. Dale - what an impressive outing! You guys are having so much fun. I wish I was still mobile. Keep up the good work.

    ReplyDelete
  2. Dale - what an impressive outing! You guys are having so much fun. I wish I was still mobile. Keep up the good work.

    ReplyDelete

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