This week for Flora and Fauna Friday we look longingly towards the bountiful boughs of Red Mulberry (Morus rubra).
Red Mulberry is a small midstory tree found in forest understories throughout all of South Carolina and the Eastern United States. Here on the Sea Islands, I most often find it reaching about thirty feet in height, squarely within the midstory below a hardwood canopy, and growing on well-drained but moist and fertile upland soils. Its growth form is an umbrella, with long arching boughs towering and spreading upward into a dome-shaped canopy. Each sinuous limb holding aloft emerald-green leaves often as large as an outstretched hand. These leaves have a rough, scaborous texture on the hand, like sandpaper. Their shape is also highly variable. Red Mulberry leaves are trimorphic in nature, having three distinct shapes. They can either be a nearly circular swollen heart-shape with a small pointed tip, or instead a three-lobed form falling somewhere between the shape of a fleur-de-lis and a trident or, lastly, somewhere in between with the shape of an oven mitt. These trimorphic leaves are incredibly distinct and make Red Mulberry easy to identify in the wild. When its leaves are lacking in winter, that arching trunk and the rather smooth, finely fissured dull-gray bark gives this tree’s identity away to the perceptive naturalist. Yet, the most defining feature of Red Mulberry is its fruit.
In April, Red Mulberry begins to bloom with its small and pendulous pale-green catkins dangling from every leaf node down its limbs. These wind pollinated flowers are easy to miss and short lived. Once pollinated the flowers mature into a clustered fruit, similar in shape to an elongated raspberry or blackberry. Within the span of a few weeks these fruits rapidly ripen, turning from pastel-green to pink, then ruby-red, and eventually purple-black when fully ripe. These fruits are short lived on the limb and a favorite food of every animal in the forest. Red Mulberry fruits are plucked as fast as they can mature by every patrolling songbird. The few that mature and make it to the ground are soundly sucked down by any passing quail, turkey, turtle, deer, fox, squirrel, opossum, or raccoon that chances upon them. Red Mulberries are a tremendous spring food source for practically every forest creature. These fruits are edible for humans as well and apparently quite good. However, I can’t personally provide commentary myself. Despite having a Red Mulberry tree in my own yard, I’ve never once eaten a fruit off of it. The critters never leave me any to try!
We have a second species of Mulberry here in the Lowcountry as well, the White Mulberry (Morus alba) which is an exotic species introduced from Europe. It’s easily told apart by from Red Mulberry by its leaves, which are a bit smaller, smooth to the touch, and in their lobed forms take on a more fig-like appearance. Its bark is usually paler and its fruit more variable in color once mature, averaging more towards a pale-red. White Mulberry is most often found in urban areas and the margins of major highways and railroads, where it has escaped from yards and gardens thanks to birds spreading its seeds. White Mulberry can become invasive in areas of high disturbance with little natural habitat. Yet I rarely see it causing issue in wild areas of the Lowcountry. It more so fills a void left in the wake of industry and sprawl.
This week for Flora and Fauna Friday we’ve stumbled upon the mock moccasin, the Banded Watersnake (Nerodia fasciata).
Watersnakes, as the name implies, are a genus of aquatic snakes that spend their days in the swamps, rivers, ponds, and bays of the Carolinas hunting fish, frogs, salamanders, and aquatic invertebrates. During the day they can most easily be found sunning or lounging on stumps, fallen logs, shrubs, culverts, rocks, and banks in or along wetlands. Often they are more active at night, hunting croaking frogs and sluggish fish under the cover of darkness. Once supper is caught, Watersnakes swallow their prey whole and alive without venom or constriction.
Although the Banded Watersnake is my focus for today, I’d like cover our other Watersnakes in brief detail. Here in South Carolina we have five species of Watersnake: the Banded Watersnake (Nerodia fasciata), Plain-bellied Watersnake (N. erythrogaster), Green Watersnake (N. floridana), Brown Watersnake (N. taxispilota), and Northern Watersnake (N. sipedon).
The Northern Watersnake is restricted to the upstate here in South Carolina, where they live in a wide array of aquatic habitats, particularly streams, rivers, lakes, and ponds. They grow to about three feet in length and have a body patterned with a checkerboard of alternating brick-red squares over a base of coppery bronze. Their diet consists of a diverse array of amphibians and small fish.
The Brown Watersnake is found throughout the coastal plain of South Carolina and is specialized to a life living in major rivers, as well as the reservoirs, streams, swamps, and oxbows along their courses. They often reach four feet in length and their body is checkerboard patterned, with dark walnut-brown blocks atop a base of neutral-brown. They are strong swimmers and piscivorous, specializing on a diet of fish, with a strong preference for catfish.
The Green Watersnake has the narrowest range in the state out of our five Watersnakes, being found only in two disjunct areas: the backwaters of the central Savannah River and the swamps of the lower coastal plain from the Waccamaw to the Edisto River. They are specialized to a life patrolling still or slow moving freshwater marshes. They average three to four feet in length and have a body colored a dark olive-green with narrow zig-zags of black crossing their back. Their diet consists mainly of fish and frogs.
The Plain-bellied Watersnake is found across nearly all of South Carolina and lives in a wide array of habitats and wetland systems. They are highly mobile on the landscape and can be found more readily than other Watersnakes in ephemeral wetlands, floodplains, isolated ponds, pocosins, ditch systems, or out in the uplands trekking between wet areas. They readily grow to three feet in length and are distinctly colored, with a dark ruddy-brown back and a belly as orange as Carolina clay. Their diet is skewed more towards frogs than fish, on account of them often hunting in fish-free ephemeral and isolated wetlands.
The Banded Watersnake, our focus for today, resides throughout the coastal plain of South Carolina. They can be found in practically every freshwater wetland system in the Lowcountry, from major rivers and lakes, to expansive blackwater swamps, to ephemeral pools and suburban drainage ditches. They are our most abundant Watersnake here on the Sea Islands. Being as widespread as they are, the Banded Watersnake’s diet is equally diverse but, like our other Watersnakes, consists primarily of frogs and fish. They generally grow about two-and-a-half feet long and can be quite varied in coloration and patterning. Often, they have a reddish-brown body ringed in bands of ebony black. With age and size, these bands often blur together turning the snake nearly black across the back.
All our Watersnakes are non-venomous and no threat to man nor pet. However, they often have a short temper and a bad attitude that has not helped them escape undue persecution. Watersnakes mimic the venomous Cottonmouth (Agkistrodon piscivorus) when threatened. They flatten their heads into a broad triangle to resemble a Viper and coil their bodies into a threatening posture. Their keeled scales, a trait they share with our Vipers, help them complete their menacing look. Yet, if you look closely, they lack the vertical “cat’s eye” pupils of a Viper. If approached or touched Watersnakes generally bite without hesitation. This is all just a bluff to convince you to let them be. The Banded Watersnake is a particularly good mimic as it is the same size, body shape, and a similar color and pattern to the Cottonmouth, with which it overlaps in range and habitat. Sadly its success as a mimic leads to a lot of Banded Watersnakes being mistaken for Cottonmouths, and then pointlessly killed by people every year.
As I’ve said before, and will say again, snakes aren’t out cruising around looking for people to bite. Just think about it for a second. Even our largest snakes here in South Carolina can’t eat anything bigger than a squirrel. Why would they risk life and limb (well maybe not limb) harassing humans and dogs? The vast majority of our snakes are nonvenomous and so the vast majority of snakes killed each year are harmless. Even with the Vipers, most snake envenomations are caused by people trying to pick-up, move, or kill a venomous snake. A snake’s primary defense is camouflage; they freeze and pray you don’t see them. If you spot them, the jig is up and they will attempt to flee into cover. But if escape isn’t possible and or they are cornered or grabbed, biting is the only chance they have to save their scaly hide. A snake doesn’t know your intentions, and every day in nature is filled with life or death dilemmas for wildlife. All the snake knows in this situation is that it may only have seconds left to live. Can you really condemn a creature for just wanting to stay alive? Spare it the spade! If you find a snake in the wild, leave it be. Appreciate it, photograph it, but let coiled snakes lie.
This week for Flora and Fauna Friday we find swaying in the sea breeze the blooms of Beach Sunflower (Helianthus debilis).
Beach Sunflower, sometimes called Cucumberleaf Sunflower, is a species native to all the Gulf States and found throughout Florida. Thanks to man it has moved its way up the Eastern Seaboard and now calls most barriers islands in South Carolina home. Beach Sunflower is a subtropical species, growing as a perennial where winter freezes are scarce and mild. Yet, in colder climes it can persist as an annual thanks to being a prolific re-seeder. Beach Sunflower has a very low growth-form for a Sunflower, growing as a bushy groundcover with creeping stems just ankle high above the ground. This is an adaptation to resist strong and sustained winds. Its leaves are opposite and triangular in shape. Its flowers grow low as well, not much more than a foot above the soil. Their flowers fit the traditional mold for our native sunflowers. An ebony-black disk, flecked with the lemon-yellow light of anthers is ringed in dozens on golden yellow petals to produce a showy two to three inch compound flower. In late April, the flowers of Beach Sunflower begin to appear here in South Carolina. They provide a bounty of pollen and nectar to our native bees, butterflies, and other pollinators from spring to throughout the dog days of summer.
Beach Sunflower is one of those species that sits squarely in the gray area between exotic and native, being native to the southeast but not to South Carolina specifically. Regardless, it has found its way into a niche here thanks to its drought tolerance, heat resistance, and ability to survive on infertile, sandy soils. This allows Beach Sunflower to grow within the dune systems of our beaches, providing a splash of color and a pocket of pollinator habitat alongside our native flora. It also does well in cultivation and can be a valuable asset to butterfly and pollinator gardens on weathered sand ridge soils or in urban areas.
This week for Flora and Fauna Friday we find washed ashore a scribbled scroll of shell telling a tale from our natural history, the Lettered Olive (Oliva sayana).
The Lettered Olive is found from North Carolina west to Mexico living near-shore along sandy bottomed inlets and beaches. Lettered Olives are marine snails, in the Gastropod order with slugs and land snails. Lettered Olives grow up to two-and-a-half inches in length. This makes them one of the larger marine snail species found here in South Carolina. Their thumb-sized shell is pill shaped with an obtuse point on one end and a long, narrow opening, called an aperture, running almost the entire length of their shell.
Through this aperture the Lettered Olive interacts with the outside world. From the blunt end of its shell it extends its head, the tube-like siphon it uses to breathe, its sensory tentacle, and its broad, ribbon-like foot which fills the full length of its aperture. Lettered Olives are particularly abundant on the beaches of South Carolina. This is thanks to the height of our tides and the dynamic conditions of our inlets and shoreline. This concentrates the sea life that depends on shallow, sandy waters into the surf zone. Most importantly, this creates the perfect habitat for the small Coquina Clam (Donax variabilis), a favorite food of the Lettered Olive. Our Lettered Olive is a prodigious predator that patrols surf swept beach sands, plowing just below their surface in search of Coquina and crustaceans. When an Olive stumbles onto a suitable snack, it surrounds and smothers it with its sinuous sole and sinks below the sand to savor its seafood supper. Safely below the beach it slowly shreds its dinner with its rasp-like tongue, its radula, as it holds and digests it within its foot.
The Lettered Olive’s shell is unique not only for its shape but for its pattern and finish. It gets its common name from the hieroglyphics scrawled along the length of its shell. Runes written on the rolled scroll of its form tell the tale of its life, its history penned upon its very body. These glyphs are inlaid below the gloss of its glazed exterior. This uniquely pristine porcelain façade on a snail this large is thanks to the polishing performed by its expansive mantle. The mantle of a mollusk builds its shell as it grows. Most species keep their mantle tucked inside the aperture, out of harm’s way. Lettered Olives instead sheath the mount of their shell with their mantle as they burrow beneath the sand, burnishing its exterior to a high gloss and sparing the shell from the scouring of coarse sand.
Lastly, we have a pair of fun facts. The Lettered Olive was first described to science in 1834 from South Carolina by Dr. Edmund Ravenel. Dr. Ravenel was one of the founders of MUSC and one of the first naturalists to study shells in detail, a field he helped pioneered that today is known as conchology. One-hundred-and-fifty years later, in 1984, the Lettered Olive was made the state shell of South Carolina.
This week for Flora and Fauna Friday we have an imperiled tree that, like sand sliding off a bluff, is silently slipping away from our Sea Island landscape, the Bluff Oak (Quercus austrina).
Bluff Oak is a small oak growing to roughly sixty feet in height. Its trunk is straight and sheathed in fine flakes of platinum-white bark. Often that trunk is blemished with small burls or studded by small low-hanging limbs blending upward into a tall crown. The deciduous leaves of Bluff Oak are a rich emerald-green and feather-esque in shape. These leaves are the length of your outstretched hand but relatively narrow and pointed, with seven-or-so irregular, shallow lobes. They’re not the easiest oak to identify. Yet, their twigs are reddish brown with strongly pointed buds. This is a subtle feature that helps separate them from their closest relatives among the white oaks. Their lime-green acorns are fairly large and sought after by deer and turkeys, if the squirrel and Jays don’t claim them first.
Bluff Oaks grow in the Deep South from Mississippi to North Carolina and down through North Florida. Yet, they are known from only a smattering of trees from a handful of counties in each state. They’re most often encountered perched on a bluff overlooking a marsh or river. Here on the South Carolina Sea Islands, fertile well-drained soil in maritime fringe forests in view of the marsh and with a stable shallow water table seems to be their preferred natural habitat. But that comes with a caveat. Bluff Oaks are weird.
Very few people, if any, have a good handle on what makes Bluff Oaks tick in their natural habitats. They occupy a very narrow niche in the Sea Island ecosystem. A niche that was historically quite stable but today quite rare due to the meddling of man. You see, Bluff Oaks love to live on bluffs, with a panoramic prospect of the marsh or a view down a bend in the river. But that’s most people’s favorite place to live as well! That’s bad luck for the Oaks. Untold scores have been clear-cut for waterfront development over the last 75 years. Many of the mature Bluff Oaks still alive today are nestled quietly in people’s yards, on church grounds, near boat landings, or on old government lands along rivers. Long before large-scale residential development began sweeping through the South, Bluff Oaks were imperiled by logging and agriculture. Clearcutting for fields on fertile sands removed mature trees from all but the bluff margins. Bluff top plantation houses displaced them further. The old trees that survived on the landscape then had the stability of the shallow water pulled out from under them by ditching and diking. Drying or flooding the few trees still hanging on. Their progeny subsequently clung to cliff faces, marsh margined peninsulas, and remote islands that were too impractical to farm and which foresters found inconvenient to plant in pine. Many of the surviving Bluff Oaks were likely intentionally spared the axe, due to their compact growth and long crown making them unfit for lumber, and thus not worth the fuel to haul to the mill. Or that’s the history I at least surmise led to their near demise.
Bluff Oaks were rare to begin with, grew in inconvenient locations to access, and had little economic value. So people paid them little attention. Meaning we have a very poor understanding of what their historic range used to be. Now that there are so few left, it’s incredibly difficult to fit enough puzzle pieces together to see the full picture of their ecology. I suspect they’re a botanical relict of a bygone time. An arboreal artifact from an ancient age, likely a species that thrived before the last ice-age, compressed by climatic swings and then pushed towards the brink by our hands. The Bluff Oak’s distribution is incredibly disjointed, with tens or hundreds of miles between populations. Those populations are rarely more than a half-dozen trees. Most are just one or two trunks. Less than ten sites are known with more than ten trees. That means there is next to no gene flow between populations. Often, there are no saplings growing that can replace mature trees when they perish. They are a declining species on the path to oblivion.
But all hope is not lost! Bluff Oaks actually do well as a shade tree in coastal suburbs and developments. They even thrive when reintroduced to their natural habitats on bluffs and banks. We haven’t pushed this species off the bluff yet! There is a space for them in the modern world. We just need to lend a helping hand. Right now, there is active research underway led by the North American Land Trust, in partnership with the US Forest Service and several Arboretums, to collect acorns and scionwood from Bluff Oaks across the country. These acorns and grafts will be grown out into mature trees as living seed banks. The USFS is even starting a nursery for Bluff Oaks in SC within the Francis Marion National Forest. The acorns produced by these nursery and specimen trees will be used for conservation of the species across the Southeast.
You can help in this effort too! The most important thing this research needs help with is finding new Bluff Oak populations. Currently, only one single site in Charleston County is known with surviving Bluff Oaks. Those seven trees are standing proud today on one of EIOLT’s conservation easements, right here on Edisto Island. Which means there very well might be a Bluff Oak standing on the edge of the woods right outside your window! If you think you know where a Bluff Oak is, anywhere in South Carolina, please reach out to EIOLT with the location of the tree and take some photos of the bark, leaves, and twigs if you can. We’d love to document its location, collect acorns, and help save this imperiled species.
Bluff Oak seedlings are not currently readily available anywhere for purchase for transplantation. At least not anywhere I can find online. But I’m hopefully that, in the not so distant future, they will be. And that this handsome hardwood can once again grace the banks of Edisto Island. Waving with Spanish Moss over our waterways, shoulder to shoulder with Live Oaks and arm in arm with Edistonians.
If you’d like to learn more about this research and restoration effort, please check out the below links:
https://www.internationaloaksociety.org/content/seeking-quercus-austrina-conservation
This week for Flora and Fauna Friday it’s our other red bird, the Summer Tanager (Piranga rubra).
Draw a line to a branched tine high in a pine and there you’ll find birds that shine bold of ruby and gold. With the end of winter’s cold, stepping into spring’s hold, summer’s Tanagers are pulled to the Lowcountry; they fall upon our forests once more. Summer Tanagers are part of the Cardinal family, Cardinalidae, which contains some of our most stunning songbird species. Our Summer Tanagers are no exception here. Males radiate a deep and vibrant scarlet-red across their entire body, contrasted only by beaded black eyes and a bone-yellow bill, heavy and faintly down-turned. Females are stunners too, with feathers saturated a saffron-yellow over undertones of olive-green, which shows most strongly through their wings.
Summer Tanagers spend the winter in the tropics of Central and South America. They return to the Southern United States around the spring equinox, reaching the South Carolina Lowcountry on the first week of April most years. Upon arrival, they begin establishing territories in wooded locales. They prefer patrolling open woodlands, savannas, maritime forests, field edges, and park lands. Places with wide spaced trees or an uneven low canopy. On the Sea Islands, males most often perch atop a Live Oak or pine and begin singing their own praises, a jumbled, oscillating whistle that echoes over the forest, a sonic fence to stake a claim of land. When not mending fencing or disputing borders, Summer Tanagers can be heard moving through the treetops uttering a trademark “pi-tick” call or chattering “pi-ti-tu” as they go.
Summer Tanagers are leaf gleaners and hawkers, scanning limbs and twigs for a quick insect snack but also jetting out into the air to snatch insects from the sky. They will eat a fair share of fruits too when in season. Summer Tanagers are specialized for eating bees and wasps, brazenly busting into hornet hives and ripping open wasp nests to eat their larvae or hawking bees on the wing for a honey-glazed meal. It’s not known whether they have any special resistance to bee and wasp venoms, or if they’re just fearless in the face of a free lunch.
Despite being an abundant, noisy, brightly colored, courageous killer of bees, Summer Tanagers are often hard to get good, close looks at. Like its other Cardinalid cousins, to include Grosbeaks and Buntings, they are curious but skittish creatures. Often they drop in to investigate neighborhood commotions, when Wrens and Titmice start sounding alarms, but will almost always dart out of sight if you turn your attention towards them.
This week for Flora and Fauna Friday it’s an early to rise and always dry, wetland wildflower, Goldenclub (Orontium aquaticum).
Goldenclub is found throughout the coastal plain of the Eastern United States, from the Mississippi to Massachusetts. They inhabit bottomlands, primary floodplains, backwaters, freshwater swales, mill ponds, and other shallow and slow-moving freshwater systems. In my experience around the Sea Islands, they prefer fertile floodplain wetlands with ankle deep water and some shade throughout midday. They are perennial plants and grow most often as individual floating clumps, about two to three foot around. However, under ideal conditions, they will spread through their roots below the mucky soil to form large colonies. The leaves of Goldenclub average about a foot long, are tongue-shaped, and shaded a luxurious, deep blue-green.
That bluish color on a plant’s leaves is known more scientifically as being “glaucous”. This most often originates from a waxy leaf coating, which can be seen as a silver-lining when the leaf is viewed obliquely or in strong sunlight. This waxy coating waterproofs leaves, usually to stop them from drying out in droughty conditions or intense sunlight. So, why does a plant that lives on saturated soil in standing water need to conserve water? It doesn’t! It needs to get rid of it. The waxy coating on Goldenclub is hydrophobic, repelling water. In fact, “Never-Wet” is another common name for the plant. This hydrophobic coating combined with internal air pockets forces submerged Goldenclub leaves to buoy back up to the surface, instantly shedding any water clinging to them, so they can return to the unobstructed sunlight they need to photosynthesize. This allows them to recover from, or avoid altogether, inundation during floods and intense rains. This can smother a plant in debris if it sinks, forcing it to regrow from its roots. But our Goldenclub is weatherproofed, so it can weather storms.
Goldenclub blooms in March into early April. Its flower is one of a kind: an ivory-white stalk, finger-width, a foot or more in length, and crooked midway, that’s capped by a thumb-sized golden spike of miniscule flowers. These “golden clubs” or “bog torches” give our plant its more oft used common names. Goldenclub belongs to the Arum family, Araceae, an ancient family of flowering plants best known for their strangely shaped spike-like flowers. Arums, to include our Goldenclub, are most often pollinated by flies, beetles, and the occasional desperate bee. The flowers, once pollinated, mature into a lumpy brown-green cudgel of fruits.
This week for Flora and Fauna Friday it’s one of our earliest butterflies of the year, an oft hard to find hardwood flutter-by, the Henry’s Elfin (Callophrys henrici).
We have six species of Elfin here in South Carolina: Henry’s Elfin (C. henrici), Juniper Hairstreak (C. gryneus), Eastern Pine Elfin (C. niphon), Frosted Elfin (C. irus), Brown Elfin (C. augustinus), and Hessel’s Hairstreak (C. hesseli). The Henry’s Elfin is our most common and widespread Elfin here in the Lowcountry and our focus for today. Yet, the Juniper Hairstreak is fairly common on the Sea Islands, although much more scarce. The Pine Elfin is also here but very seldom seen. The Frosted Elfin is a rare and endangered species specialized to wiregrass savannas. Brown Elfins and Hessel’s Hairstreaks are found only upstate.
Elfins are butterflies in the Gossamer-Wing family, Lycaenidae, a diverse clade of small, close winged butterflies. This family is best known in the United States for holding the Hairstreaks and Azures, both groups are often a pale gray below but blazoned above with a brilliance of iridescent blue. Elfins share a lot of similar physical characteristics to their Hairstreak cousins. However, our six Elfins are set apart by a more sedentary nature, cryptic coloration of primarily brown with hints of green, and a slightly larger size on average, at a half-inch to three-quarters-of-an-inch tall. The Juniper and Hessel’s Hairstreaks stand apart from the other Elfins, and all our Gossamer-Wings, with their wings gilded brilliantly in iridescent emerald.
The Henry’s Elfin can most easily be separated from the other Elfins by examining its hindwing, which sports a fairly distinct postmedian line, that’s the line on the outer half of the wing. In Henry’s Elfins, this line flaunts a white highlight at both the top and bottom ends. The Brown Elfin never has that bottom highlight and is generally evenly colored across both wings. However, the Frosted Elfin can have double-sided white on the postmedian line. To eliminate the Frosted Elfin, look for an isolated black dot on the hindwing, just inside from the tails that trail from the lower tip of the wing, as well as extensive frosting on the hindwing bleeding up onto the forewing. The postmedian line on the forewing of the Henry’s Elfin also tends to be straighter and flatter than the Frosted Elfin, which normally steps up and down between cells. As for the Pine Elfin, that’s a horse of a different color! Not really, it’s also brown, but its checkerboard patterned hindwing is hard to mistake for anything but an Eastern Pine Elfin!
Despite the monotonous color palette, the Henry’s Elfin is still a handsome butterfly, especially when fresh. A deep mahogany along the abdomen sparkles with pinpricks of white and the faintest iridescent wash of indigo as it smoothly transitions up into warm chestnut above and heavy walnut tones below, until we hit the postmedian lines. There a dividing line splits the wings and both turn pale. The forewing a pallid khaki wash. The hindwing frosted on its lower margin and beset betwixt with a row of dark spots. Below, our bug is stained an ash-gray with antennae and legs ringed in strikingly contrasted black and white. Like I said, a handsome butterfly!
The Henry’s Elfin is most readily found in deciduous forests in early spring. They have one brood, which generally flies from the first week of March to the end of April. They are very wide ranging and cover an eclectic assemblage of habitats. This is a butterfly that can crop up anywhere and requires trial and error to find. But, to stack the odds in your favor, you can hone in on hostplants. Hollies are a favored hostplant of the Henry’s Elfin, particularly the widespread American Holly (Ilex opaca). Eastern Redbud (Cercis canadensis) is also a host alongside several other unrelated shrubs. American Holly and Eastern Redbud are both thin-skinned midstory trees that are best adapted to deciduous forests and areas of infrequent fire, like floodplain margins. Which are the ecosystems where I’ve personally seen the most Henry’s Elfins. Henry’s Elfins are also rather arboreal in nature and will partake in nectar when convenient. Thus, try looking up and surveying the flowers of early-spring flowering trees and shrubs to further improve your odds. Watch the flowers of trees like Sweetleaf (Symplocos tinctoria), Shadblow (Amelanchier spp.), Redbud, and Blueberry (Vaccinium spp.). With enough scanning of the treetops, you can spot a Henry’s lazing around sipping on nectar or fluttering from shrub-top to shrub-top.
This week for Flora and Fauna Friday we have nature’s shag carpet, Haircap Mosses (Polytrichum spp.).
We have two fairly abundant species of Haircap Moss here on the Sea Islands, Common Haircap Moss (Polytrichum commune) and Juniper Haircap Moss (Polytrichum juniperinum). Common Haircap Moss is found nationwide and across South Carolina, but is most common in the piedmont and mountains. Juniper Haircap Moss is found throughout the United States, and is our most prolific Haircap in the Lowcountry. Yet, it is still a scarce member of our Sea Island ecology. It appears most often on the shaded margins of pine savannas, sand barrens, and dry sand ridge forests. It prefers to grow on exposed, weathered sands and is tolerant of fire and other habitat disturbance.
These two species look incredibly similar. One of the easier ways to tell them apart is through their leaves under droughty conditions. Common Haircap’s leaves have a distinct downward curve to them, which can exaggerate as they dry. Juniper Haircap, conveniently and conversely, has straight leaves that fold upward tightly against the stem as they dry. If you look really, really close at the leaf margins, Common Haircap is serrate all the way towards the tip. But you’ll likely need a hand lens to see this. Both species grow in mats on the soil’s surface, like a lush shag carpet. Each stem is usually one to three inches in height and ringed in narrow needle-like leaves, giving it the shape of a bottle brush.
In order to go any further, we’ll need to take a detour for a crash course on Moss biology. Mosses are plants, but very primitive plants. They lack the means to produce the polymer lignin. Lignin gives plant cell walls their rigidity. It’s what makes wood “woody”. Like steel reinforced concrete, lignin is the rigid cement and cellulose the flexible steel scaffold. It’s also critical to the proper structural formation of vasculature and roots in plants. Thus, lacking lignin, Mosses lack roots and the internal vasculature to transport water and nutrients around their body. Instead, they’re basically a sponge, passively wicking water from the soil’s surface and through their skin throughout the rest of their body. They must also sponge mineral nutrition from the environment, absorbing it not only from the soil but through windblown dust and ash they trap between their leaves, and from the acids and other trace nutrients dissolved in rainwater.
Now it gets weird and I have no choice but to start using the big science words. Mosses don’t reproduce with flowers nor with seeds. They pre-date both. Instead, they produce capsules and spores. But these are produced by a second plant, which grows on top of the first plant. (I told you it was getting weird.) The Haircap Moss we see, that we all know and love, is a gametophyte. It’s a haploid. It only has one set of chromosomes. It has half the genetic material of the organism, just like sperm and eggs in animals. In spore reproducing plants, including Mosses, Clubmoss, Horsetails, and Ferns, the gametophyte is the main life stage that anchors to the soil, photosynthesizes, and lives a long healthy life. The opposite is the case in flowering plants and gymnosperms (E.G. pines, cedars, cypresses).
The gametophyte of Haircap Moss, when mature, will produce a dense spiny disk at the tip of the stem. Haircap Moss is dioecious, meaning it has male and female plants. Male plants grow an Antheridium, female plants an Archegonium. When rainwater lands into the bowl-shaped male Antheridium, it splashes sperm away with it. If those droplets of water land on a nearby female Archegonium, it’ll be fertilized. From within this Archegonium cradle, a diploid sporophyte, with a full set of chromosomes, will grow directly out of the tip of the gametophyte’s stem. In Haircap Moss, this sporophyte derives all its water and nutrition by leeching from its parent gametophyte. When the sporophytes of Haircap Moss begin to emerge, they’re spear-shaped and protected by a fibrous sheath that whitens and frays away with age. The orange-brown sporophytes of Haircap Moss are shaped like a golf club when mature, with a skinny stalk holding aloft a rounded oblong lump of a capsule at a roughly right angle. This capsule will produce gamete spores and, once the sporophyte dies, the capsule dries and will pop open, scattering spores into the wind.
This week for Flora and Fauna Friday, it’s our sulfur throated spring songster, the Yellow-throated Warbler (Setophaga dominica).
On the threshold of spring, a monochrome spec smears itself across the horizon, melting upon a canvas of pale-gray moss. Then, like day’s break into the chilled sky of morning, a flash of yellow illuminates the gray. A golden glow shines from that spec, while a chorus of birdsong follows from it in kind. Our Yellow-throated Warblers are staking their spring claims.
The Yellow-throated Warbler’s summer range extends across much of South Carolina. They are most abundant on our coast and even live year-round here on the Sea Islands. They are abundant in maritime forests, the fringes of cypress swamps, and the wetland margins and valleys of pineywoods. But, pretty much anywhere on the coast with plentiful hardwood tree cover is suitable habitat for them.
Male and female Yellow-throated Warblers look much the same and are mostly monochrome birds: Black legs, black beak, black eye, black mask, gray back, white belly, and black wings broken by two heavy, white wing-bars. Their face is distinct with a strong white stripe above the eye, a white bag below the eye, and a white crescent behind the cheek that frames a black cheek patch, which blends above into a black eye-stripe and flows below like drops of black ink down its flank. This face serves as a frame for their namesake yellow throat, an explosion of rich sunflower-yellow glowing from chin to chest, sometimes radiating up to the lores in front of their eyes. From this iconic mug emerges a rather long and stout bill for a warbler, with an ever so subtle hook to the tip.
Yellow-throated Warblers are one of the earliest warblers to begin migrating north. They begin singing on Edisto Island near the end of February. Males sing a pleasant, rhythmic song of a dozen notes that fall in pitch while speeding up, before rising back with the last note or two. Pairs build their nest most often here in Spanish Moss, weaving the crook of a tangled beard into a hammock before lining it with straw and webs. I occasionally see them eviscerating the webs of spiders and tentworms for their silk, leaving the terrified web’s keeper thoroughly confused and homeless. Yellow-throated Warblers provision themselves and their young with a diet of insects and arthropods, patrolling tree branches throughout the year for tasty morsels.
