Ramble Report June 14 2018

Today's Ramble was led by Linda Chafin.

Here's the link to Don's Facebook album for today's Ramble. (All the photos in this post are compliments of Don.)

Today's post was written by Linda Chafin.

25 Ramblers met today.

Today's Reading: Linda read from African-American poet, Marilyn Nelson:

 

Ruellia Noctiflora

A colored man come running at me out of the woods
one Sunday morning about twenty years past.
The Junior Choir was going to be singing
at Primitive Baptist over in Notasulga,
and we were meeting early, to practice.
I remember wishing I was barefoot
in the heavy, cool-looking dew.
And suddenly this tall, rawbone wild man
come puffing out of the woods, shouting
Come see! Come see!
Seemed like my mary-janes just stuck
to the gravel. Girl, my heart
like to abandon ship!

Then I saw by the long tin cylinder
slung over his shoulder on a leather strap,
and his hoboish tweed jacket
and the flower in his lapel
that it was the Professor.
He said, gesturing,
his tan eyes a blazing,
that last night,
walking in the full moon light,
he'd stumbled on
a very rare specimen:
Ruellia Noctiflora,
the Night-blooming Wild Petunia.
Said he suddenly sensed a fragrance
and a small white glistening.
It was clearly a petunia:
The yellow future beckoned
from the lip of each tubular flower,
a blaring star of frilly, tongue-like petals.
He'd never seen this species before.
As he tried to place it,
its flowers gaped wider,
catching the moonlight.
suffusing the night with its scent.
All night he watched it
promise silent ecstasy to moths.

If we hurried, I could see it
before it closed to contemplate
becoming seed.
Hand in hand, we entered
the light-spattered morning-dark woods.
Where he pointed was only a white flower
until I saw him seeing it.

Show and Tell:

Mosquito Fern

In keeping with the day's theme of ferns, Linda fished some Mosquito Fern, Azolla caroliniana, out of the plaza fountain for discussion. Each frond is tiny–it’s the smallest of all the ferns, each frond less than a millimeter long and wide–and is covered with water repellent hairs. Mosquito Fern plays an important role in rice cultivation. Its tiny fronds harbor a cyanobacteria (blue-green alga) called Anabaena, which converts nitrogen in the air into a form useable by plants; rice farmers in SE Asia have been introducing Mosquito Fern into rice paddies as a natural fertilizer for thousands of years. And, despite their tiny size, the ferns form dense, fast-growing mats which smother weeds in the rice paddies. In Don’s photo, you can see the characteristic red hue of the tiny fronds, which presumably act as a sunscreen.

Today's Route:   We left the Visitor Center entrance plaza and headed down the road to the upper opening into the Shade Garden.  We proceeded though the Shade Garden and into the Dunson garden.  We exited the Dunson garden to briefly check for Gulf Fritillary eggs or caterpillars on the passionflower vines growing on the deer fence.  We returned via the road back to the Visitor Center.

Widespread Maiden Fern

We encountered our first (terrestrial) fern – Widespread Maiden Fern – along the roadside to the Dunson Garden and used its large, uncomplicated fronds to familiarize ourselves with the strange new vocabulary of ferns. Its fronds (leaves) are tall, with a greenish-yellow stipe (special fern name for the stalk) that darkens to brown at the base. The pinnae (special fern name for leaflets) are long and pointed and covered in soft hairs. On the underside of the pinnae, small, kidney-shaped structures (called sori) hold the sporangia where spores are produced.

And here’s where ferns get really complicated: they reproduce, not by seeds, but by a two-phase process called “alternation of generations.” The large plants of the Widespread Maiden Fern are sporophytes–literally spore-plants–that have a full complement of chromosomes (i.e. they are diploid, 2n, the product of sexual union). They produce diploid “spore mother cells” in their sporangia, each of which divides by meiosis, and produces 4 haploid (n) spores, each with half the number of chromosomes as the sporophyte. The spores are tiny and so lightweight they are carried far and wide by the wind, even up into the jet stream. (As a result, a surprising number of fern species have a global distribution.) If a spore is lucky enough to settle in a nice, damp spot, it germinates and produces a haploid organism called a gametophyte (i.e. a gamete-plant). The gametophyte is green, very small, about nickel-sized in most ferns, and often heart-shaped. Two tiny organs arise on the surface of the gametophyte: one produces an egg (haploid), the other produces a sperm (haploid) bearing minute flagella. If conditions are wet enough, the flagellated sperm swims to another gametophyte where it (hopefully) finds a mature egg and fertilizes it. (The sperm and egg on a single gametophyte mature at different times to prevent self-fertilization.) This sexual union results in an embryo that is diploid (2n), and the embryo grows into a sporophyte–the large, showy fern we saw today. The two generations referred to in the name are the sporophyte generation and the gametophyte generation.

This seems like a risky process–one highly dependent on weather–but ferns have survived since the Carboniferous Period, 300-400 million years ago. However, compared to seed plants–especially to the flowering plants–ferns are not very diverse, species-wise. There are only approximately 10,000 fern species in the world, compared to about 450,000 flowering plant species. The lack of diversification is probably due to their ancient reproductive strategy.

A Mirid bug on Widespread Maiden Fern

Two-lined Spittlebug on Widenspread Maiden Fern

Sharp-eyed ramblers noticed lots of very small insects on the Widespread Maiden Fern, and Don identified them as Two-lined Spittlebugs and tiny, brown plant bugs (Family Miridae). Ferns are largely free of insect pests, so we were a bit surprised to find these little bugs here, but, possibly, they were just visiting.

Once we were in the Dunson Garden, we took time to look at the two growth forms that ferns have. Ferns have underground stems only, called rhizomes. Some ferns put up all their fronds at the growing tip of the rhizome, so the plant has a clumped form, with the fronds emerging in a sort of fountain-shaped cluster. Other ferns put up fronds every inch or two along the rhizome, so the fronds appear either in a line or with a scattered appearance.

Christmas Fern: One of the most common ferns in Georgia,

Christmas Fern can be identified by its evergreen fronds and pinnae shaped somewhat like Christmas stockings. Last year’s fronds will remain around the base of the plant till they disintegrate in late spring. Its fronds are clustered.

Cinnamon Fern:  Found in wetlands throughout Georgia,

The "hairy armpits" of Cinnamon Fern

The clustered fronds of Cinnamon Fern

 Cinnamon Fern can be identified by its “hairy armpits” [small tufts of white or tan hairs at the base of each pinna) and by the separate fertile frond that arises in the middle of the clump and is covered with cinnamon-colored sporangia. Its fronds are clustered.

Royal Fern

 

Royal Fern:  Another clumped fern, Royal Fern is found in wetlands throughout Georgia. Its sori are borne on several modified pinnae in a cluster at the very top of the fertile fronds. The clusters are green at first but turn brown and last till late in the fall.

Marginal Wood Fern

Marginal Wood Fern showing the marginally located and rounded

 sori

Marginal Wood Fern: This fern’s name reflects the fact that its tiny, rounded sori are lined up along the margins of the pinnae (which are alternate). Marginal Wood Fern is an evergreen fern, with last year’s fronds lingering around the base of the plant till they disintegrate in late spring. It is mainly a mountain species and in occurs in clumps on rich, wooded slopes.

Goldie's Wood Fern

Goldie's Wood Fern: This fern is pretty rare in Georgia, occurring in loose clumps only at high elevations in cool, moist, rocky habitats such as boulderfields. The pinnae are mostly opposite and are a goldish-green color. The rounded sori hug the midvein of the pinnules.

Ebony Spleenwort

Ebony Spleenwort showing alternate pinnae

Ebony Spleenwort with sori on underside of pinnae

Ebony Spleenwort: Another widespread and common fern, Ebony Spleenwort is easy to identify. Look for its shiny, black stipe and rachis and small tufts of fronds. The pinnae are clearly alternate. It will grow in poor, dry-ish acidic soils that most other ferns won’t touch.

Southern Lady Fern

 

Southern Lady Fern pinnae

Southern Lady Fern showing sori on underside of pinnae

Southern Lady Fern: Common throughout Georgia in wet to moist habitats, Southern Lady has hairless stipes (“southern ladies always shave their legs”! ha!) and alternate pinnae that abruptly taper at the tips. The reddish stipes are also distinctive in the lowlands; at high elevations they are usually green.

Southern Maidenhair Fern

 

Northern Maidenhair Fern

Northern Maidenhair Fern with light green bands of sporangia

Georgia has two species of maidenhair ferns:  Northern Maidenhair Fern and Southern Maidenhair Fern, occurring respectively in north and south Georgia (mostly). Northern Maidenhair fronds are broadly horseshoe-shaped, with the pinnae radiating out like a fan from the top of the black, wiry, erect stipe. Southern Maidenhair fronds have a similar stipe, except they are usually drooping from rocks and limestone walls and bluffs in the Coastal Plain. In both species, the pinnae are delicate and fan-shaped, with the sporangia tucked under small flaps of tissue along the edges of some pinnae. Both species grow only where soil moisture and pH are high.

Sensitive Fern

Sensitive Fern: A common fern of wetlands throughout Georgia, Sensitive Fern is called that because of its susceptibility to frost, not because the leaves are responsive to touch. Its sterile fronds are broadly triangular with many deeply cut lobes. The sori are held at the top of a separate stalk in a dense cluster of bead-like sporangia. The fronds are irregularly spaced along the creeping rhizome.

New York Fern

New York Fern showing the smaller basal and apical pinnae

New York Fern: Common in cool, moist areas of north Georgia, a New York Fern’s frond tapers to nearly nothing at both ends “because New Yorkers burn their candles at both ends.”  It’s a spreading fern, producing its light green fronds in rows on long, widely creeping rhizomes. It’s common in the mountains to see whole slopes or coves covered with this fern.

Broad Beech Fern

Broad Beech Fern: Another common north Georgia fern found in moist habitats, Broad Beech has a roughly triangular frond with the lower two pinnae spreading at an angle, giving the blade the shape of a fox’s head with two erect pointed ears. Also notice how the pinnae tissue extends along the stalk between the pinnae. Its fronds are scattered along a widely creeping rhizome.

Black Cohosh

 

June in the Piedmont is usually a lull between the early spring wildflower extravaganza and the summer flush of composites, mints, and legumes. However, Black Cohosh always brightens the green monotone of the Dunson Garden this time of year, with its tall, candelabra-like inflorescences rising high above other plants in the herb layer. We were all surprised to learn that the flowers (puffs of white stamens without petals) smell pretty awful to humans. They must smell pretty good to bees, which were present on nearly spike we examined.

Solomon's Plume with developing fruits

Many spring-blooming wildflowers are now in fruit in the Dunson Garden. Solomon's Plume is in early fruit, with the cluster hanging heavy at the tips of the stems. The fruits will turn a silvery-red as the summer progresses.

Jack-in-the-Pulpit with immature green fruit

Jack-in-the-Pulpit fruit are also still green. Two years of heavy rains have resulted in many of Dunson’s “Jacks” becoming “Jills” – robust, five-leaflet “female” plants now setting fruit. (Good years of rain and abundant nutrients support the energy-expensive process of producing fruits the following year.)  Later in the summer, the heavy fruiting heads will droop to the ground, bringing the red fruits into easy reach of ground-feeding birds such as Wild Turkey and Wood Thrush. I wonder if Box Turtles eat the fruits, or do they stick to their favorite May Apples?

Road (Deer Fence):

Lizard Tail is flowering in the wetland zone at the western end of Dunson Garden.

Tall Scouring-rush, a species of horsetail (not a true rush), grows among the Lizard Tail. Like ferns, horsetails are ancient plants, dating from the Carboniferous Period, that also reproduce from spores.

Small Gulf Fritillary caterpillar on Passionflower leaf

Our beloved fence of Passionflower vines is now officially supporting one of the first Gulf Fritillary caterpillars.

A Mississippi Kite was seen flying over the ROW, a popular feeding area of these beautiful raptors who show up here every summer from their South American winter homes.

SUMMARY OF OBSERVED SPECIES:

Mosquito fern	Azolla caroliniana
Widespread Maiden Fern (aka Southern Maiden Fern and Southern Shield Fern)	Thelypteris kunthii
Two-lined Spittlebug	Prosapia bicincta
Plant bug	Family Miridae
Christmas Fern	Polystichum acrostichoides
Cinnamon Fern	Osmundastrum cinnamomeum
Royal Fern	Osmunda regalis
Marginal Wood Fern	Dryopteris marginalis
Goldie's Wood Fern	Dryopteris goldiana
Ebony Spleenwort	Asplenium platyneuron
Southern Lady Fern	Athyrium filix-femina ssp. asplenioides
Northern Maidenhair Fern	Adiantum pedatum
Southern Maidenhair Fern	Adiantum capillus-veneris
Sensitive Fern	Onoclea sensibilis
New York Fern	Thelypteris noveboracensis
Broad Beech Fern	Phegopteris hexagonoptera
Black Cohosh	Actaea racemosa
Solomon's Plume	Smilacina racemosa syn. Maianthemum racemosum
Jack-in-the-Pulpit	Arisaema triphyllum
Passionflower	Passiflora incarnata
Gulf Fritillary (caterpillar)	Agraulis vanillae
Tall Scouring Rush	Equisetum hyemale
Lizard's Tail	Saururus cernuus
Mississippi Kite	Ictinia mississippiensis