Saturday, September 3, 2016

Ramble Report September 1 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, except where noted, in this post are compliments of Don.)
Today's post was written by Dale Hoyt.

No. attendees: 20

Today's reading: Dale read an excerpt from an article by Alvaro Jaramillo, Take Note of Taking Notes, that appeared in Bird Watcher's Digest, 2016, vol. 38(6): 33-37:

Identifying vs. Recognizing
What do we wish we could do as birders? Well, remembering details is important. We would like to remember that the least sandpiper is the one with the yellowish legs and that the Philadelphia vireo has dark lores and a bolder face pattern than the warbling vireo. . . . If we have gone through the mental gymnastics of figuring that out once, why does it not stay? How many times will we have to see a fox sparrow before we are certain that it is a fox sparrow and not the smaller, daintier, and duller-billed (in color) song sparrow? Doesn't bird identification sometimes seem like the movie Groundhog Day? It seems like we replay various scenarios over and over again, and eventually they sink in, if we are lucky. We are trying to juggle a seemingly endless set of details that we need to remember: leg color, wing bars, crown stripes and so on. Eventually, that thought process of identification becomes automatic; you won't have to think about the details of what makes a streaky sparrow a song sparrow, it will just automatically reside in your brain in the same way you recognize friends or family. Essentially, we do not identify our friends: we recognize them. [emphasis added] It takes a bit longer, but eventually you also just recognize birds, not identify them. There will be fewer and fewer that you need to work through in a point-by-point identification as you become more and more experienced. But what is key here? Memory.

Nature Ramblers at Sher & Barbara Ali's treehouse
The Ali's, Sher and Barbara, invited everyone to a pizza luncheon at their Treehouse in Winterville. About a dozen Ramblers took advantage of their generosity and enjoyed enormous quantities of pizza, soft drinks and scrumptious chocolate cake. Thank you, Sher and Barbara!

For the remainder of the year our Rambles will start at 8:30AM. (The last Ramble is November 17.)

Don discovered Slender Ladies' Tresses orchids in his yard while mowing this week. Look for photos on his Facebook album this week.

Today's route: We took the mulched path to the upper end of the Dunson Native Flora Garden, crossed the road on the White trail and walked to the power line right-of-way. Turning right we walked uphill a short distance, then reversed direction and walked down the RoW, crossing the access road and went a short distance toward the river. Then we returned to the road and walked up to the cement walkway back to the Arbor.

Carolina or Green anole basking in a Winged Elm
No Ramble during the summer months would be complete without seeing at least one lizard, and we did at our first stop. Tom spotted a small Carolina or Green anole in the upper branches of a small Winged Elm, basking in the early morning rays of the sun. I've written about anoles in the two previous posts. If you've missed those you might want to go back and see if they satisfy your curiosity. (To find earlier posts just use the Blog Archive on the right side of the page. It will give you access to all our Ramble Reports.)

The inflorescence of a red Hurricane lily; those are the stamens projecting out in front of the petals.
In the lower part of the Shade Garden are a dozen or more Hurricane Lilies (also known as Surprise Lily or Red Spider Lily). These flowers are native to China and Japan and are in the Amaryllis family, which means that nearly every part is toxic, so deer will leave them alone. The Hurricane name refers to the late summer season in which the flowers appear, about the time when hurricanes or tropical storms begin to threaten the Atlantic coastal states. The odd thing about the plants is that the flower and foliage appear at different times of the year. The naked stems with their flowers emerge suddenly during late summer (the origin of the Surprise name) but the foliage only appears after the flowers are gone. It persists sometimes through the winter and then disappears in the spring. There is no sign of the plant during the summer until the flower stalk pops up again in August.

We spent some time today looking at trees. Our focus was, as today's reading suggested, identifying trees, with the hope that we will all be able to recognize different trees in the future. To that end here are some terms that help us communicate the characteristics of trees (and other plants, as well).

The parts of a simple leaf and a compound leaf
What a leaf is: There are actually two types of leaves, simple and compound. Simple leaves are just single, flat green things attached to a twig or stem. They might have a smooth shape, wavy edges, lobes, points or other shapes. Examples of familiar trees with simple leaves are Oaks, Dogwood, Sweet Gum or most Maples. But other trees, like Pecans or Hickories, have compound leaves – leaves that are made up of many smaller leaflets. For most beginners this poses a problem: how do you tell a leaf from a leaflet? There are two ways. You can wait until autumn and see what the largest unit that falls off a tree is. That largest unit is the leaf. The second way doesn't require waiting that long. At the point where the leaf is attached to the twig there is a bud. The bud looks like a small, dark-colored bump. Inside the bud is a developing leaf or shoot that will appear next year. So if you look carefully at where the leaf is attached and don't find a bud you are looking at a leaflet of a compound leaf. (In a few plants the bud is concealed by the leaf stem that connects the leaf to the twig, so this rule only works about 99.9 % of the time.) You can also look for the base of the petiole, which is usually (but not always) swollen at the point where it is attached to the twig. If what you think is the petiole is not swollen and there is not bud at that point, then you're probably looking at a leaflet. With a little experience looking at tree leaves you'll soon be able to recognize compound leaves pretty easily.

This is the first step in learning to identify or recognize different trees: are the leaves simple or compound?

The next step is to see how the leaves are arranged on the twig or branch: alternate or opposite. Those terms are pretty clear. If you look at a twig and see that the leaves are paired, one on each side of the twig at the same point, they are opposite. Alternate leaf arrangement is the opposite of opposite. (A few plants have a whorled leaf arrangement – three or more leaves that emerge from the stem at the same point.)

The first group of trees we looked at today mostly had simple, alternate leaves. The two exceptions were the Hickory, which has compound leaves, and the Mimosa, which has doubly compound leaves..
American Beech: Smooth, gray bark (often with initials carved in it); simple, alternate leaves with wavy edges (bluntly serrate) and papery thin.
Winged Elm; not the corky ridges on the twig and the jagged edges of the simple leaves.
Also the size and shape of the leaves is helpful: small and eye-shaped.
Winged Elm: Small, simple, alternate leaves with saw-toothed (serrate) edges, eye-shaped (symmetrically pointed at each end); twigs and young branches often, but not always, with corky ridges, called "wings."
Deep, blocky ridges are characteristic of Sourwood trees.
Sourwood: Older trees have bark that is thrown up in thick ridges; simple, alternate leaves that are symmetrically pointed at each end and much longer than wide. Nectar is a source of excellent honey with a long shelf life. The trunk often grows with more twists and turns than other trees.
The light gray bark and simple leaves with rounded lobes tells you this is a White Oak.
White Oak: Simple, alternate leaves that are have rounded lobes; lobe ends lack sharp, prickly point. Bark is gray or light gray in color and on the upper trunk it is shingle-like in appearence.
The roughly cross-shaped Post Oak leaf.
Post Oak: Simple, alternate lobed leaves; two lobes larger than the others, giving the leaf a rough cross shape.
Fruits of Hophornbeam; each papery sack encloses a single seed.
Hophornbeam leaf; look closely to see the doubly serrate edges.
Hophornbeam: Simple, alternate lobed leaves with saw tooth edges and some of the teeth have tinier saw teeth on them, making them doubly serrate. Older bark is "shreddy," looking like a cat scratched it. The wood is among the densest of all North American trees and very resistant to breaking. The common name comes from the fruits, which resemble the Hops used to flavor beer and use of the wood to yoke oxen.This small, understory tree is one of the commonest in the natural areas of the Botanical Garden.

The compound leaves of Ailanthus are arranged alternately on the stem.
A small tree/shrub with compound leaves gave us some identification problems. Don and I both thought it was a Sumac, but Don looked closely at the leaflets and discovered that they had finely serrate edges, which Sumac lacks. So what is it? We finally settled on Ailanthus (also known as Tree of Heaven), a tree from Asia was once widely planted in urban areas of the northeast. (It is the tree in "A Tree Grows in Brooklyn.") Ailanthus tolerates urban pollution, grows rapidly, produces thousands of seeds and has a distinctive, foul odor.

The doubly compound leaf of Mimosa.
Someone handed me a leaf from a Mimosa, a widely planted and invasive small tree in the Bean family. It has compound leaves with a vengence -- they are doubly compound. In the picture above I'm holding one single Mimosa leaf. You can see that each of the leaflets is further subdivided into many miniature leaflets. 

The red berries and simple, alternate leaves of Carolina Buckthorn.
The berries will turn black when they are ripe.
On the southwest corner of the White trail where it intersects the road is a small tree that I never noticed for five years. Weds. I noticed that it had red berries and I puzzled over its identity, consulting several references and never reaching a comfortable decision. I tentatively thought it might be a Deciduous Holly, but there is a labeled Deciduous Holly in the Dunson Garden and its leaves bear no resemblance to this tree. Today Don figured out that it was a Carolina Buckthorn, a very uncommon understory tree. The red berries were what led me down the garden path; they become black when they mature.

River Oats or Fish-on-a-Pole

River Oats is a neat looking grass that resembles its other common name: Fish on a Pole. It is a self-seeding perennial and speads easily. Some gardners think maybe a little too easily. One of our Ramblers remarked that they heard Elaine Nash say that it was the only plant she knew that would eliminate Microstegium (an introduced, highly invasive Asian grass). If I got the story right, Elaine planted River Oats with or near the Microstegium and kept mowing the area. After three years the Microstegium was gone and the River Oats had taken over. This may have worked because Microstegium is an annual grass. The plant dies after it has set seed and frequent mowing would remove the flowers before they could produce any seed. After the first year any new Microstegium would arise from existing seeds in the soil. That seed bank would decrease year after year if it was not renewed. This would not be a practical solution in situations that cannot be easily mowed or mowed with religious regularity.

The part of the power line RoW north of the White trail is being actively managed to create a Piedmont prairie, an ecosystem that used to be common in the piedmont of Georgia. The Piedmont prairie was dominated by grasses and forbs with widely scattered trees. Last year Garden personnel and volunteers planted hundreds of native prairie grasses and herbs and the Lanier Center is currently propagating more plants.
The hill south of the White trail was part of the formal garden years ago and is now a lawn dominated by Bermuda and Fescue grasses. The long term plans are to also convert it to a prairie, but to do that the lawn grasses must be removed so that native grasses can be established there. Right now the garden is testing ways to eliminate these non-native grasses and that is the purpose of the square plots you see to the south. (Earlier in the year a graduate student, Lauren Muller, told us about these plans.) Once the most efficient and effective method of getting rid of Bermuda grass is determined this area will also be converted to a prairie.

One of the grasses in the prairie is seen as a purple haze floating above the vegetation. The haze is produced by the massed flowering heads of the Purple top grass. If you grasp the flower stalks of this grass and pull it through your hand you will be left with a waxy feeling that is responsible for the other common name for this grass: "Greasy grass."

Frostweed stem showing the "wings" that give the group the common name: Wingstem.
A different species of Wingstem with wings on the stem.
The white flowers of Frostweed
The commonest herbaceous plants in the power line RoW are probably the three kinds of wingstems in the genus Verbesina. The first of these to bloom is the white flowered Frostweed which can be seen in flower here as well as in the flood plain. The other two species have yellow flowers and are still mostly in bud at present. The wingstems get their name from the thin strips of leafy tissue that grow along the length of the stem. There is some variation in this characteristic, however. You can find some plants in which the wings are almost absent and some in which they are only present on part of the stem.

Sweet Autumn Clematis flower (non-native species)

Sweet Autumn Clematis leaflets have smooth edges

Virgin's Bower (native species) leaflets have roughly toothed edges.
Today we saw two kinds of Clematis, Virgin's Bower, our native species,  and Sweet Autumn Clematis, an introduced and very aggressive species. They look very similar but the easiest way to tell them apart is to examine the edges of the leaflets. Those of Virgin's Bower have roughly toothed edges, while the leaflet edges of Sweet Autumn Clematis are smooth.

Silvery Checkerspot on my hand;
the white centers in some black spots toward the edge of the hind wings are diagnostic for this species.
On the lower part of the power line RoW I held my hand up to shade my eyes from the sun and something landed on it -- a Silvery Checkerspot butterfly. It stayed there for several minutes, long enough to warm up and have its picture taken. Then it was off for other adventures.

Gulf Fritillary caterpillars;
the one on my thumb has just recently hatched; the larger one is nearing the size to form a chrysalis
Gulf Fritillary chrysalis (photo taken last year)

Gulf Fritillary chrysalis; the coloration varies from white to brown.

Gulf Fritillary adult
Purple Passionflower fruits
On the way back to the Arbor we walked up the road and stopped at the Purple Passionflower growing on the deer fence. It was loaded with ripening fruits and Gulf Fritillary caterpillars! We also found a chrysalis attached to the fence! The different Parrionflower species are the only plants that this butterfly feeds on.

Caterpillar of Imperial Moth
Imperial Moth (photo taken last year)
This large caterpillar was found on the sidewalk in the Shade Garden. Carmen Champagne, the fine naturalist at Sandy Creek Nature Center, identified it for me. It is the larva of the Imperial Moth. The fine hairs growing out of its body are not normal. Most silk moth larvae are not this hairy. In fact, these hairs look like a fungal infection, so it is probably ill. One of the Ramblers wondered why it was so large. The adult moths in this family (the Silk moths, family Saturniidae) do not feed as adults; they have vestigial mouth parts and couldn't feed if they wanted to. The adult moths only live a short while, a week or less, in which they mate and lay eggs. All the energy they need to produce eggs or search for mates has to be acquired in the caterpillar stage of development. So the caterpillars really pack it away. Some of them can reach the size of hot dogs. The imperial moth is further unusual for our large Silk moths -- it pupates underground. The caterpillar digs into the earth and forms a hollow cell in which it overwinters as a pupa, the adult emerging the following spring.

That's all, until next week!

Winged elm
Ulmus alata
Oxydendron arboreum
Carolina/Green anole
Anolis carolinensis
Rattlesnake fern
Botrychium virginianum
Jack in the pulpit
Arisaema triphyllum
Hurricane/Surprise lily
Lycoris radiata
Oyster mushroom
Pleurotus ostreatus
Carolina buckthorn
Ramnus caroliniana
American beech
Fagus grandifolia
Yaupon holly
Ilex vomitoria
White oak
Quercus alba
Post oak
Quercus stellata
River oats
Chasmanthium latifolium
Ailanthus shrub/Tree of Heaven
Ailanthus altissima
Ostrya virginiana
Mockernut hickory
Carya tomentosa
Albizia julibrissin
Wild (Neopolitan) garlic
Allium neapolitanum
Purple-top grass/greasy grass
Tridens flavus cupreus
Virginia buttonweed
Diodia virginiana
Sweet autumn olive clematis
Clematis ternifolia
Mountain mint
Pycnanthemum incanum
Frostweed/White crownbeard
Verbesina virginica
Red-banded hairstreak
Calycopis cecrops
Carolina desert chicory
Pyrrhopappus carolinianus

Rabbit tobacco
Pseudognaphalium obtusifolium
Flowering spurge
Euphorbia corollata
Silvery checkerspot
Chlosyne nycteis
Tall thistle
Cirsium altissimum
Yellow crownbeard
Verbesina occidentalis
Virgin's bower
Clematis virginiana
American pokeweed
Phytolacca americana
Wild heliotrope
Heliotropium amplexicaule
Vaccinium corymbosum
Spotted beebalm
Monarda punctata
Various hibiscus

Deciduous holly
Ilex decidua
Passiflora incarnata
Gulf fritillary caterpillar
Agraulis vanillae
Gulf fritillary chrysalis
Agraulis vanillae
American beautyberry
Callicarpa americana
Garden orbweaver spider
Neoscona crucifera
Imperial moth caterpillar
Eacles imperialis
Bird's nest fungi
Nidulariaceae family


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