Saturday, August 28, 2021

Ramble Report August 26 2021

Leader for today's Ramble: Linda
Link to Don's Facebook album for this Ramble
Number of Ramblers today: 28
Today's emphasis & Route: Flowering plants in Elaine Nash Prairie Project/Georgia Power right-of-way, via the Lower Shade Garden and White Trail Spur.

Reading: Emily read the entry on Pawpaw from A Natural History of Trees of Eastern and Central North America by Donald Culross Peattie.
   The first reference to this curious species of an otherwise notably tropical family occurs in the chronicles of Desoto's expedition in the Mississippi valley in 1541, for naturally an edible fruit of such size was important to a host of conquistadores always near starvation. But, after that, for two centuries the Pawpaw flourished unknown save by wild animals and red men, until Mark Catesby delineated it in his Natural History of Carolina, that master work whose plates are fresh with wilderness still.
   Once abundant in the Mississippi valley, where it formed dense thickets of wide extent, the Pawpaw is today in the northeastern stages only a scattered understory tree, though to the south it may become 30 to 40 feet tall, with a straight trunk more than a foot in diameter. Everything about it is odd and unforgettable. The leaves are among the largest in our sylva, and in autumn, when they turn a butter yellow, they are the mellowest of the season's tones. The flowers, with their exotic look borrowed from tropical relatives, hardly seem to belong to the cool vernal world on which they open. At first green the petals soon turn brown, and then they become a dark winy color, with an odor to match, a remembrance of fermenting purple grapes. As to the fruit, the better it grows, the uglier, for it is only when it is thoroughly mature, in late fall, that it is edible. At first the skin is greenish yellow; gradually it darkens, and when it is nearly black. wrinkled, and looks unappetizing - in October or November - at last the yellow or orange flesh is soft, custardy, and palatable.
   Pawpaws have had their enthusiasts from the days of the Creeks. Cheraws, and Catawbas, who often planted them, to the present. Such wood-wise people know that there are good and bad trees, as to flavor, and have long insisted that selection would soon result in marked improvement of the fruit; in general, the orange· fleshed variety is considered much more tasty. Pawpaws were made into a jelly by the early settlers, and still in southern towns sometimes appear in the markets. The seeds contain a powerful alkaloid which, it has been noted, has a stupefying effect on the brains of animals, yet opossums are great Pawpaw eaters, and raccoons and gray squirrels also appreciate the fruit.
   For the wood there are no uses, but the inner bark was woven into fiber cloth by the Louisiana Indians, and the pioneers employed it for stringing fish. In its range a characteristic part of American country life, the Pawpaw, for all its exotic kinship, seems an intensely native tree, above all in the frosty autumn, when the leaves droop witherIng on the stem and the great plashy fruits hang preposterously heavy on the twigs.


Show and Tell
Pawpaw fruits showing variation in size.
Contrary to Peattie's description, these were ripe when the skin was turning yellow and the fruit felt soft.

Largest Pawpaw sliced open showing the yellow flesh and black seeds.
The seeds are each surrounded by an aril, similar to persimmon seeds.

Over twenty years ago Emily and Dale planted three Pawpaws in their backyard. It took them fifteen years before that produced the first fruit, which disappeard before it could be harvested. The three trees have suckered profusely and they now have a real Pawpaw patch. It's produced a lot of fruit and Emily brought samples for the Ramblers to taste. Dale didn't think they were as delicious as the one he ate 62 years ago.
 
Dangerous eating
One of the Ramblers was interested in using Dog Fennel to spice up their salad because it smelled like Dill. DON'T DO IT. Dog Fennel is covered wtth a dangerous substance called a pyrrolizidine alkaloid. It can cause fatal liver damage if eaten. Cattle and horses have been killed by inadvertently eating Dog Fennel that was mixed with hay.
 
Announcements/Interesting Things to Note:
"       Sean Cameron, Education Coordinator at the Garden, talked to us about the joint State Botanical Garden-U.S. Forest Service iNaturalist native plant project to document native plants and their habitats on U. S. Forest Service lands in the piedmont and north Georgia.  The project is geared towards documenting existing pollinator habitat and identifying areas that can be developed with pollinators in mind. See this website for more information:
iNaturalist:    https://www.inaturalist.org/projects/georgia-grasslands-initiative-ggi

"       Roger mentioned that Sandy Creek Nature Center is still in need of trail guides.  Contact Kate Mowbray at 706/613/3615 or Katemobray@accgov.com

"       Several people asked about access to the new Porcelain Arts Museum. Sign up for a free tour with a docent here:  https://botgarden.uga.edu/porcelain-and-decorative-arts-museum-timed-access-now-available/

LIST OF OBSERVATIONS:

Lower Shade Garden:

Cardinal Flowers
It comes as no surprise that Cardinal Flower -  with its bright red tubular blooms - is pollinated by Ruby-Throated Hummingbirds, drawn to the copious nectar produced by glands on the inside of the tube. The flowers open from the bottom of the flower cluster up - this is obvious in Don's photo where withered flowers are hanging on to the lower portion of the cluster while fresh flowers are open at the top. Each flower goes through two phases. First, the stamens, tipped with brush-like anthers, emerge from the tube and present their pollen ("male phase"), as you can see in the close-up photo below. Then, as that flower matures, the stamens wither and are replaced by the style and stigma in the same position ("female phase"). Meanwhile, freshly opened "male phase" flowers higher up in the cluster are beginning to present their pollen. Since hummingbirds work a flower cluster from the bottom up, they visit the lower "female phase" flowers first on a particular plant, ideally contacting the stigmas and leaving behind pollen picked up from the topmost "male phase" flowers of a previously visited plant. As you can see in Jen Goellnitz's photo, the hummingbird's head brushes nicely up against the upper part of the flower, either depositing or picking up pollen, depending on whether the flower is in its "female" or "male" phase.

Close-up of single Cardinal flower
photo by Helen Lowe Metzman,
public domain, https://www.usgs.gov/media/images/lobelia-cardinalis-3-cardinal-flower-howard-county-md

Image of Hummingbird hovering over a Cardinal Flower bloom,
photo by Jen Goellnitz, https://www.flickr.com/photos/goellnitz/36414685015

Swallowtail butterflies are also attracted by the bright color of Cardinal flowers. Even though there is no landing platform for them to rest on while they sip nectar, they grasp the petals and insert their proboscis down the floral tube. However, their shape is not as perfectly fitted for the Cardinal flower as are hummingbirds and they are less effective as pollinators.

Virginia Jumpseed
Style branches, with curled stigmas, protrude from the tips of the
flowers

Variegated Virginia Jumpseed is a cultivar of the native Virginia Jumpseed (or Knotweed), horticulturally selected for its colorful leaves and flowers. Typical of all species in the Smartweed Family, there is a sleeve of tissue at the base of each leaf that wraps around the stem; this sleeve is called an ocrea. Although tiny, these inconspicuous flowers attract a variety of bees and wasps.

Surprise Lily aka
Hurricane Lily, Red Spider Lily, and Naked Ladies is in the Amaryllis Family.

Bristly fruits of the Canada Black Snakeroot.


The exotic invasive, Sweet Autumn Clematis, has grown into the canopy of trees along the White Trail. As of this writing, Gary has treated the stout basal stem of this plant with herbicide. (photo by Gary Crider)

Sensitive Partridge Pea
The leaflets fold up when touched, a reaction believed to discourage browsing.

Trailing Lespedeza is a mat-forming member of the Bean Family.


Arrowhead Orbweaver at rest on web.
Tom and Halley found this Arrowhead Orbweaver wrapping its prey in silk
(multiple strands of silk emerging from spinnerets)


Elaine Nash Prairie Project/ROW:

Spotted Bee-balm (or Horsemint) flowers are yellow with maroon spots, but they are upstaged by the pink bracts that surround the base of each whorl of flowers.
 
 
Avis pointed out mud tunnels made by termites on the sides and top of a wooden stake in the edge of the ROW
If you ever see mud tunnels on the side of your house's foundation you probably should call a Pest Control Service.

Seed heads of Big Top Lovegrass, one of the earlier warm-season grasses to flower.
Cone-headed Katydid
The antennae are longer than the body and the head is cone-shaped.

Flowering Spurge flowers lack petals. The white structures are actually appendages of nectar glands.

A Grasshopper nymph; notice how short the antennae are, compared to the Katydid, above.


Rose-pink or Bitterbloom, an atypical member of the Gentian Family.



St. Andrew's Cross, a member of the St. John's-wort genus, Hypericum


Yellow Star-grass - not a grass but a close relative of the irises.
 
Introduction to the Aster Family

Late summer, early fall is the season of the Aster Family, also known as the Composite Family. The latter name refers to the flower heads that are typical of this family, each head being a composite of two types of flowers that, together, superficially resembles a single flower. The classic composite flower head has a central disk of many tiny flowers, surrounded by a showy whorl of ray flowers, the whole thing held together by a cup-shaped structure called an involucre (in-voe-loo-ker). The involucre is made up of few to many tiny bracts. Though small these bracts are important for identifying members of this family. Are they solid green in color or marked with white diamonds or red edging? Are they hairy or smooth? Do they have long, tapering points or blunt triangular points or no points at all? Do they cling tightly to the base of the head or curl outwards? These involucre features are important for separating the many look-alike members of this family.

Red-margined involucral bracts

The eponymous members of this family are the asters: Georgia Aster, New England Aster, Heath Aster, and many (many) more in our region. In the New World, the genus Aster is now split up and scattered across several genera; in Georgia, we have seven genera of plants that were once in the single genus Aster. The Europeans got to keep their Asters; us New World plant lovers get to learn a lot of new Latin names. Sigh.

Georgia Aster, with white and purple disk flowers and purple ray flowers, blooms in October and early November. It is now in the genus Symphyotrichum.

Some of the most common and conspicuous of the late summer composites are sunflowers, in the genus Helianthus. They are typical composites, with flower heads composed of a central disk of maroon or yellow flowers and a whorl of golden ray flowers.

Woodland Sunflower - both disk and ray flowers are yellow.

Once you've accepted the fact that Composite Family "flowers" are actually flower heads made up of many disk flowers and ray flowers, it is time to face another fact - that some members of this family are black sheep, flouting the rules that define this family. One group of these scofflaws discarded its rays and has only disk flowers while another group of species dispensed with disk flowers and has only rays.

Disk-only flower heads are especially common in late summer and fall bloomers. Think of the ironweeds, thistles, blazing stars, and Joe-Pye-weeds that light up roadsides, rights-of-way, ditches, and gardens in late August. These disk flowers are relatively large and most have long, colorful style branches that raise the sticky stigma surfaces up into wind-blown currents of pollen grains. These showy features play the role that ray flowers typically do: they attract pollinators.

Tall Thistle

Blazing Star

Elephant's Foot

Ray-only flowers seem to predominate in the spring and early summer - think Dandelion, Green-and-Gold, Carolina Desert-chicory, Hawkweeds, and Chicory - though they are found in the fall too.

Both types of flower heads have the all-important involucre and both types are the result of the same evolutionary pressures: to make available to pollinators multiple flowers in a small space. In a single visit, a pollinator is able to probe and pollinate several (or many, depending on the species) flowers. This pollination efficiency has allowed the composite family to diversify into the highest number of species (32,000+) of all the plant families and to spread across all the continents but Antarctica.


 SUMMARY OF OBSERVED SPECIES:
Passionflower     Passiflora incarnata
Cardinal flower     Lobelia cardinalis
Variegated Jumpseed     Persicaria virginiana
Sanicle/Black Snakeroot     Sanicula sp.
Surprise/Hurricane Lily     Lycoris radiata
Sweet Autumn Clematis     Clematis terniflora
Sensitive Partridge Pea     Chamaecrista nictitans
Creeping-bush Clover     Lespedeza repens
Arrowhead Orbweaver     Verrucosa arenata
Two-lined Spittlebug     Prosapia bicincta
Spotted Horsemint     Monarda punctata
Elephant’s Foot     Elephantopus tomentosus
Dog Fennel     Eupatorium capillifolium
White Crownbeard     Verbesina virginica
Big Top Lovegrass     Eragrostis hirsuta
Cone-headed Katydid     Neoconocephalus sp.
Virginia Buttonweed     Diodia virginiana
Purple-top/Grease Grass    Tridens flavus
Flowering Spurge     Euphorbia corollata
Late Flowering Thoroughwort     Eupatorium serotinum
Rabbit Tobacco     Pseudognaphalium obtusifolium
Grasshopper          Orthoptera: Acrididae
Autumn Olive     Elaeagnus umbellata
Rose Pink    Sabatia angularis
St. Andrew’s Cross     Hypericum hypericoides
Yellow Star Grass     Hypoxis hirsuta
Mountain Mint     Pycnanthemum pycnanthemoides
Blazing Star Liatris     Liatris sp.
Tall Thistle     Cirsium altissimum
Keeled Treehopper (nymph)     Entylia carinata