Ramble Report October 10 2019

Today's Ramble was led by Dale Hoyt.

Here's the linkto Don's Facebook album for today's Ramble. (All the photos in this post are compliments of Don, unless otherwise credited.)

Today's post was written by Dale Hoyt.

Today’s Focus: Trees along the White Trail and Service Road.

22 Ramblers met today.

Announcements:

1.     Katherine reminded us that Advanced Voting for the November election will begin October 14. Click here for a list of each place where you can vote early.
There is only one item on the Athens Clarke County ballot – the SPLOST referendum. Sandy Creek Nature Center has a proposal to update some of their displays, so it is important that you vote. A vote for the SPLOST proposal is a vote to the fund the SCNC proposal.

2.     Linda is doing well after surgery on Monday. She is back home and will be recovered in 4-6 weeks. She has a stack of books and has already finished one of them.

3. Kathy S. gave away several bags of Joe Pye Weed seed.
4. Avis’ birthday today!

Today's reading: Dale read the October 23^rd entry from Donald Culross Peatties’ An Almanac for Moderns:

THE pale green maps of the lichens, sprawling across certain boulders that I pass on my regular walks, are as well known to me as the shapes of the five continents. Year by year I never see a change in them. I cannot honestly suggest that they have grown an inch in any dimension, and by all accounts the lichen is the slowest-growing colony inexistence. There is every evidence that some of the great lichen patches upon inaccessible cliffs, where nothing could ever have disturbed them, are older than Sequoia sempervirens! This ought to deter one before stripping these little gray yet green elders from their niches where they cling with such a desperate grip. They go further north than any other plants, nourishing the reindeer; they scale the cliffs of the Himalayas where men faint and die; yet they flourish most richly of all in the tropics. To them I owe the color and the delectable odor of my ragged old Harris tweed coat, dyed with the lichens orchil and cudbear that the children of the isle of Harris gather. Innumerable are the lichen dyes, of which the most famous is litmus; to lichens many a man and beast has owed his life, on the steppes of Tartary, the muskegs of Athabasca, the tundra of Iceland. Beyond question the lichen is often the first plant upon the barren rock, the first bringer of life to the stones.

Today's route: From the Arbor through the Dunson Garden to the White trail to the old access road, and return on the Green Trail.

White Trail:

A large Berkley Polypore mushroom.

One of the nice things about the Rambles is that nearly every week brings a surprise. The surprise this week was a Berkeley Polypore at the base of an Oak tree near the edge of the woods where the White Trail enters the woods. This large mushroom astounded us all with its size. For more information you should visit Michael Kuo’s website, MushroomExpert.com.

It is not a coincidence that this mushroom is growing at the base of an oak tree – it’s a parasite and will eventually kill the tree.

Earlier ways of classifying mushrooms were based, in part, on their structure. All the mushrooms that produced spores from gills that hung down from the mushroom’s cap were in one group. Another group was made up of mushrooms that produced spores from tiny pores on the underside of the cap. These polypores were thought to be distantly related to the gilled mushrooms. For many years the gilled and polypore mushrooms were assumed to be only distantly related. But DNA sequencing showed that the Berkeley polypore was more closely related to the gilled mushrooms than it was to other polypores.

Mockernut Hickory bark with its metallic grid-like appearance.

Several kinds of Hickory grow in the Garden. The Mockernut Hickory has very unique bark: the ridges of the bark are arranged in diamond-shaped patterns that are quite distinctive.

Hickories have compound leaves that are alternately arranged on their twigs.

A fallen tree with the spiral, twisted grain exposed.

A dead Northern Red Oak has stood for many years near the point where the White, Green and Blue Trails meet together. This tree has finally fallen, probably toppled by one of the violent thunderstorms earlier this year. The bark is gone, revealing the way the grain is twisted. If you were a squirrel and ran up the trunk, following the grain, you would move to the left. Almost all trees have a twist to their grain, but only a small minority twist to the left like this one. (Later we found another downed trunk with a right-hand twist.) No one seems to know why twisting to the right should be so common.

Old Service Road:

Many different kinds of trees grow alongside the old Service Road. The easiest way to identify them is from the leaves, so we searched the ground for fallen leaves. Other, smaller, subcanopy trees had leaves that were low enough for us to actually collect from the tree.

Leaves, even on the same tree, vary a lot. The position of the leaf on the tree makes a difference in its structure. Leaves low on the tree or on the north side get less sunlight than trees at the top or on the south side. As a rule of thumb: the more light the smaller, thicker and darker green they are. Less light: leaves are larger, thinner and paler green. These differences are adaptive. Leaves exposed to higher winds need to be smaller to reduce water loss. At the same time, on the top of a tree, they can pack in extra layers of green, photosynthetic cells to capture more of the intense light. Leaves in the shade are not exposed to high winds and can have a larger surface area to capture the attenuated sunlight.

Because of this variability you need to sample several leaves from the same tree, if possible.

We saw 4 or 5 kinds of Oaks today. In our area there two categories of oak trees: Red Oaks and White Oaks. These differ in many significant ways:

		Acorn characteristics
	Leaf lobes	Mature	Germination	Tannin levels
White Oaks	Rounded	First year	In Fall	Lower
Red Oaks	Pointed, with bristle tip	Second year	Spring of next year	Higher

Tannins are bitter tasting compounds. If you’ve ever tasted a persimmon before it’s ripe you know how it “puckers” your mouth. That was tannin that did that. When squirrels are preparing for winter they gather acorns and bury them for later retrieval. White Oak acorns are frequently eaten, instead of being buried. When they do bury them, the squirrel will often bite off the bottom end of the acorn, where the plant embryo is located, thus preventing the acorn from germinating. Red oak acorns are buried intact.

Oak leaves; from left to right:
Southern Red Oak (sun leaf)
Southern Red Oak (shade leaf)
Scarlet Oak,
Northern Red Oak

Southern Red Oak leaves have a rounded leaf base. If you hold the stem of the leaf between your thumb and first finger, allowing the leaf to hang down you should note that it is shaped like a bell with a prominent clapper. If that image doesn’t work for you, think of the leaf as a ballet dancer wearing a tutu. The sun leaves are often not three lobed. They are long, skinny and the big vein that runs the length of the leaf is usually curved slightly, like the blade of a sickle or scythe.

Southern Red Oak bark lacks the “ski trails” found on Northern Red Oak and Scarlet Oak.

You can find the distribution of the Southern Red Oak here.

Northern Red Oak leaves in silhouette.

Northern Red Oak trunk, showing the "ski trails."

Northern Red Oak leaves are broad and the space between lobes, called “sinuses” don’t extend very far into the leaf (shallow sinuses). This helps differentiate the leaf from the Scarlet Oak, which has very deep sinuses.

Northern Red Oak bark has “ski trails.” The top of the bark ridges is smooth and reflects light, making them look like paths that run up or down the trunk, reminiscent of the appearance of ski tracks in the snow.

You can find the distribution of the Northern Red Oak here.

Scarlet Oak leaves have pointed lobes, like other members of the Red Oak group. The sinuses (spaces between lobes) are very deep, compared to the Northern Red Oak.

This oak has “ski trail” bark similar to the Northern Red Oak.

You can see the distribution of the Scarlet Oak here.

Post Oak

Post Oak leaf showing the Maltese Cross shape.

Post Oak is a member of the white oak group. It’s leaves are in the shape of a Maltese Cross – two prominent lobes in the middle of the leaf extend at right angles to the axis of the leaf.

Silhouette of the Blackjack Oak leaves.
Notice the three lobes on most of the leaves.

Blackjack Oak is a member of the red oak group. It was a surprise to see it here because we have visited the Old Service Road for nine years and this is the first time we’ve noticed this tree. The leaves are usually three-lobed and bristle tipped.

You can see the distribution of Blackjack Oak here.

Black Gum leaves are beginning to turn color.
Note the small branches growing at right angles to the trunk.

Black Gum is one of the earliest trees to show fall color. The leaves are rather nondescript, as far as identifiable features. One easy character is the branches: they arise a right angles to the trunk.

American Beech leaves and buds.
Notice how long and sharp-pointed the buds are.
The leaf margins are "wavy"; you might not be able see the small bristles at the edge of each wave.

American Beech is the most easily identified of our native trees. It has smooth, gray bark and, in areas where a lot of people visit, initials and confessions of love are always inscribed on the trunk. Something about a uniform, smooth surface seems to attract adolescents.

In addition to the characteristic bark, the leaves and the leaf buds, are also unique. The buds are elongate, brown and sharp-pointed. They resemble pointed cigars. The leaves have a texture that is unique and hard to describe. They also have wavy edges with tiny bristles at each peak. The mnemonic for remembering this is: “You find waves at the beech.”

Elsewhere in the Garden today Tom found a lot of beech fruits on the sidewalks. They are spiny and about the size of a fingernail.

Hop Hornbeam (or Hophornbeam) Is a small, understory tree that has simple, alternate leaves with doubly serrate margins. (Serrate means “like a saw” or the edge you get when you cut cloth with pinking shears. Doubly serrate means that there are serrations of two different sizes.)

Hop Hornbeam fruits

Fruits of the Hop vine, used to flavor beer.

The first part of the name, “Hop,” is a reference to the fruit of the tree. It resembles those of the Hop vine, a plant product that imparts a bitter flavor to beer. 

The second word, “hornbeam,” is a little more esoteric. It refers to a method of yoking a team of oxen. If you attached each ox independently to a cart, they might injure each other. If one turned its head to the left it might gore the ox to its left. To prevent this people tied a stout stick to the horns of both animals. When one turned its head the other’s head was forced away. The stick had to be stout and the wood that was used in European countries was called “hornbeam.” When Europeans settled the New World they found our tree, which looked like the European hornbeam, and had similar strength and resistance to breaking when bent. That’s how it got its name. (If not, it makes a good story.)

As it was getting late, we returned via the Green Trail to celebrate Avis’ birthday with a chocolate-hazelnut cake.

SUMMARY OF OBSERVED SPECIES:

Berkeley’s Polypore fungus	Bondarzewia berkeleyi
Mockernut Hickory	Carya tomentosa
Southern Red Oak	Quercus falcata
Scarlet Oak	Quercus coccinea
Northern Red Oak	Quercus rubra
American Hophornbeam	Ostrya virginiana
Blackjack Oak	Quercus marilandica
Ebony Spleenwort	Asplenium platyneuron
American Beech	Fagus grandifolia
Blackgum	Nyssa sylvatica
Post Oak	Quercus stellata