Did you ever wonder why the garden soil in Spring smells so distinctive? It’s fairly well-known that the odor is caused by soil bacteria that produce a volatile substance. But, as the late Paul Harvey used to say, here’s “The Rest of the Story.”

While browsing the latest issue of Popular Mechanics Linda came across an article that ties the production of that Spring odor to a tiny soil insect called a springtail.  

Most people have never seen springtails because they are so small and live mostly in the soil and leaf litter. Some species can be seen on the surface of snow in winter. They are called “snow fleas” because they look like little black dots jumping about the snow surface. They are propelled by an extension of their abdomen that lies folded under their body. When disturbed this structure is released, flipping them into the air. That’s why they are called “springtails.”

To learn how they are related to the odor of Spring you should read the Popular Mechanics article. 

A Crane Fly Notice there is only a single pair of wings. The second pair are highly modified into structures called “halteres”. The halteres can be seen in the photograph just behind the wings. They look like miniature Tootsie Pops, if you remember those. The wing span of this Crane Fly is a little over an inch. (Click on the photo to enlarge it; the halteres are then easier to see.)

Spring is the time of year when Crane Flies are most commonly seen. Many people think they are giant mosquitoes, but these flies do not bite. In fact, most of them live only a few days. Long enough to mate, lay eggs and die.

Crane Flies are “true” flies — they have only one pair of wings. The second pair is highly modified to form a pair of structures called halteres. When the fly is flying the halteres are constantly vibrating. As the fly moves in space the moving halteres act like a gyroscope, enabling the fly to sense the position of its body in space and correct it to the desired flight path. (The Wikipedia page on Halteres explains this function in considerable depth.) 

The larvae of these flies feed on decomposing vegetation. I’ve found them in decaying leaves when I’ve cleaned out the gutters on our house and you can also find them in compost piles.

Besides being mistaken for mosquitoes, Crane Flies are sometimes confused with Daddy Long Legs because of their long, gangly legs. (Daddy Long Legs don’t have wings and are not even Insects. Insects have three pairs of legs; Daddy Long Legs have four pairs.)

Today’s Ramble was led 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, unless otherwise credited.)

Today’s post was written by Dale Hoyt.

22 Ramblers met today.

Announcements:

Don announced
that Debbie Cosgrove needs someone to assume her duties as curator of the
Durham Herb Walk at Scull Shoals in the Oconee National Forest in Greene County.
Anyone interested can contact Don here.

Don has created two maps of the Shade Garden and Dunson Garden areas, each labelled with the names of the subareas used by the curators in charge of each garden. We will put these online for your use. Thank you, Don!

As of March 13, the Botanical Garden will remain
open while the University suspends instruction for two weeks, beginning March
16. Check often for updates.

Today’s Focus:
The Dunson Native Flora Garden and the power line right of way.

Today’s reading:
March is Aldo in Athens month and the Nature Ramblers are participating by
beginning each Ramble with a reading from Aldo Leopold’s work. Today was a
slightly condensed reading of The Geese Return from Leopold’s Sand
County Almanac, pp. 18-23. (You can find a slide show with the complete
text of the essay here.)

Today’s route:
From the Arbor to the Dunson Garden, then to the power line right of way and
down to the river. Return via the power line right of way and the White Spur Trail
to the Children’s Garden.

LIST OF
OBSERVATIONS:

Remember, you can enlarge any photo by simply clicking on it. Click again or press ESC to return.

Lower Shade Garden:

Trilliums started blooming in the Dunson Garden about a week and a half ago. All the Trilliums in Dunson were planted by the Garden staff as there were none found here when the Garden was surveyed by Charles Wharton in 1998. He remarked that why they were absent was a mystery as they were found in the Gainesville Nature Center.

The Trilliums are divided into two groups: the Toad-shades and the Wake-robins. In the Toad-shade group the flowers sit directly atop the three leaves. They also have strap-like petals the range in color from yellow through green, bronze and dark brown or purple. In contrast, the Wake-robins have stalked flowers that project above or below the level of the three leaves.

Like many spring ephemerals the trilliums produce seeds that have elaiosomes, fatty, protein-rich “handles” that attract ants. The ants carry the seed back to their nest, remove the elaiosome to feed to their brood, and discard the seed. Thus the seed gets dispersed a short distance from its parent plant.

After the seed germinates it spends the first year in the soil, growing its rhizome. The next year it will produce a single leaf above ground and the following years it adds one leaf until it reaches three leaves. Altogether it will take five to seven years before it produces a flower. 

Cluster of Sweet Betsy Trillium

Year old Sweet Betsy Trillium single leaf

Many of the trilliums in the Dunson Garden show mixtures of features that suggest they are hybrids between the species planted there. In particular the Chattahoochee Trillium seems to be involved many of the putative hybrids.

Chattahoochee Trillium with its tall stem and silvery white stripe down the middle of the lear.

Another early blooming species is the Golden Ragwort. A perennial plant, it overwinters as a rosette of kidney shaped leaves that resemble those of violets. In early spring it sends up flowering stalks and their leaves have a completely different shape; they are elongate and finely lobed. Ragworts are in the aster family and produce seeds with fluff that enables them to disperse carried by the wind.

Most species of ragwort are highly toxic, carrying compounds that attack the liver.

Golden Ragwort

Many of the fallen trees are decorated with bracket fungi, mushrooms that resemble the tail feathers display by “tom” turkeys. All these mushrooms are at work breaking down the woody tissue of the tree. The mushroom is the reproductive structure of the fungus; it produces spores. Unseen by the human eye is the body of the fungus. It’s a group of microscopically thin threads that penetrate the wood, secreting digestive enzymes that break down the walls of the tree’s cells and absorbing the resulting carbohydrates. Without the fungi the dead trunks of trees would accumulate and soon we’d be up to our waist in tree limbs and trunks.

False Turkeytail Mushrooms

Dunson Native Flora
Garden:

The first cluster of trillium we encountered appeared to be extremely short stalked. The leaves looked like they were resting directly on the ground. But looks are deceiving. It is the stalk that lies on the ground, turning up at the leaf end. This is how this trillium gets its name: Decumbent Trillium.

Decumbent Trillium

Growing almost everywhere in the Garden is Leatherwood, one of the earliest blooming shrubs. I first saw it in flower in the first week in February, the flowers coming out before the leaves.

Leatherwood flowers

Christmas Fern is one of the commonest ferns in the natural areas of the Garden. It is evergreen, but by the end of winter the fronds are looking the worse for wear and the rhizome begins to put out new fronds. They emerge from the leaf litter tightly coiled and then the coil unrolls as fronds elongate. At that stage they resemble the ends of a stringed instrument, hence, the name “fiddle head.”

Christmas Fern “fiddleheads”

One of the wake-robin trilliums is blooming, the newly named Georgia Trillium. It was formerly a subspecies of the Dwarf Trillium.

Georgia Trillium

Allegheny Spurge, sometimes referred to by its genus name, Pachysandra, makes a nice ground cover. The sexes of its flowers are separate, male flowers occupying the upper part of the inflorescence and female flowers the lower portion. It is possibly pollinated by beetles.

Allegheny Spurge flowers; male flowers are white, femle flowers below the male flower and dark red.

 Cut-leaf Toothwort is still blooming.

Cut-leaf Toothwort

 There are two kinds of Trout Lilies in the Garden, American Trout Lily and Dimpled Trout Lily. The American forms a large colony of plants at the base of tree; the Dimpled is planted elsewhere. The name refers to a depression the develops at the end of the seed capsule, marking the place where the style was attached to the ovary.

Seed capsule of Dimpled Trout Lily The dimple has the remnants of the style projecting from it.

Dimpled Trout Lilies

 Virginia Bluebells start out pink and change to blue as the petals open. A similar change occurs in Hydrangia where it is controlled by the pH of the flower.

Virginia Bluebells

 Autumn Fern is native to Japan and seems to becoming a little invasive. It should probably be removed from the Dunson Garden.

Autumn Fern

Autumn Fern sori (the dark spots) on the underside of the frond.

Southern Lady Fern

Autumn Fern and Southern
Lady Fern were both found growing among some rocks beside the path.

Celandine Wood Poppy flower bud

Celandine Wood Poppy will be blooming before long. Right now it’s still beginning to develop flower buds.

Purple Cress

Purple Cress, also known as Douglass’s Toothwort is found in the northwestern corner of Georgia where the limestone deposits of the Cumberland plateau enter our state.

Bloodroot

Bloodroot is blooming in the Lower Bog area of Dunson, next to the path.

British Soldier lichen

If you look carefully between the slats that make up the small footbridge to the access road, near the Yucca planting, you will see some tiny, red-capped lichens. They are known as British Soldiers and have been growing in this same location for as long as we can remember.

Pussytoes

Pussytoes are blooming, but it’s hard to tell. The flowers never open much. They are the favored food plant for the caterpillars of the American Painted Lady butterfly.

ROW:

Purple Dead-nettle

Purple Dead-nettle is a naturalized non-native in the mint family. It is typically found in disturbed area: lawns, the edges of roads, plowed fields. The odd name is really descriptive. First, the flower is purple in color. Last, the leaves resemble those of stinging nettles. Second, the leaves don’t sting or irritate, so you could consider them dead as far as stinging goes. So . . . Purple Dead-nettle.

Two other mint species, Ground Ivy and Henbit, are often confused with Purple Dead-nettle;  here’s hot to tell them apart. 

Henbit flowers are redder and the stem leaves clasp the stem.

Ground Ivy grows horizontally over the ground and has wider, darker purple flowers.

All three of these mints have flowers that never open; they produce seed by self-pollination. This is insurance for when the regular flowers fail to attract bees.

Goldenrod Spherical Gall

Avis found one of last
year’s Goldenrod Spherical Galls. A gall is an abnormal growth on a plant. The spherical gall is induced when a fly lays an egg in the growing tip of a goldenrod plant. The plant continues to grow and the part where the egg was laid begins to swell, providing food for the fly maggot inside. The larva overwinters and the following spring pupates. During the winter small birds like Chickadees and Titmice discover the galls and peck a hole in them to extract the fly-sickle. A yummy winter treat, rich in fat and protein.

American Wild Violet, sometimes called Johnny-Jump-Up.

Another common early spring plant is the Johnny-Jump-Up, also known as the American Wild Violet. It often grows in disturbed areas and is similar to two other Violas that look very much like it.

We stopped at the temporary pool that forms after every flood/heavy rain, hoping to see frog eggs. We did find tadpoles, but the egg masses of Leopard Frogs weren’t visible. 

WHITE TRAIL SPUR:

Witch’s brooms in Hophornbeam tree

Witch’s broom is like a gall in that it is produced by a foreign organism interacting with plant tissue. What causes these bunches of twig-like growths is not known for certain. It is likely to be a fungus infection and may have been transmitted by an insect. Trees in the birch family seem to be unusually susceptible; we find them on many of the Hophornbeams in the Garden.

Rue Anemone

Just inside the woods there is a decaying log at the edge of the path. This area has been home to a large colony of Rue Anemone for many years.

Violet-toothed Polypore mushrooms

Another bracket fungus, the Violet-toothed
Polypore mushrooms are growing on tree near the Rue Anemone. These look superficially like the False Turkeytail and they perform the same function — they are digesting the tree.

SUMMARY
OF OBSERVED SPECIES:

Today’s Ramble was led 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, unless otherwise credited.)

Today’s post was written by Dale Hoyt.

22 Ramblers met today.

Announcements:

1.     
Next week’s Ramble is the last formal Ramble of
the year.

2.     
Until formal Nature Rambles resume on March 5,
2020, we will meet Thursdays at 10 a.m. for an informal social hour whenever
the Garden is open.

3.     
After each social hour there may be a
spontaneous, leaderless and unreported ramble – wherever you want to go – or
not. (In other words, a walk in the woods.)

4.     
Here’s the schedule:

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