This week for Flora and Fauna Friday it’s the bull’s ire, the bloodshot one-shot bug, the Cow-Killer (Dasymutilla occidentalis).
The Eastern Velvet Ant, colloquially called the Cow-Killer, is found throughout the South including all of South Carolina. Cow-Killers grow to about three-quarters of an inch in length and both sexes are equally large. They sport an unmistakable coat of shiny blood-red and jet-black velvety hair. Hence the common name of “Velvet Ant”. Females are almost entirely red up top, except for black legs and a black base to and band across their abdomen. Males have a red head, red mantle on the thorax, and red tip to the abdomen with black everywhere else.
Cow-Killers are an interesting insect with many fascinating characteristics. Firstly, despite looking like giant ants, they’re really wasps. This jives better with their solitary nature and jittery movements. Females are wingless, scurrying swiftly through the grass as they search for flowers to drink from and insect tunnels to trespass in. Males have smoky-black wings and spend their time pollinating as they search for females. Often amidst courtship, male Cow-Killers will pick up their lady and carry her to a more secluded, and assumedly romantic, spot before mating. This helps explain why males are the same size as females, an odd trait for solitary wasps, since he needs to be able to fly for two. After mating comes egg laying and Cow-Killers are parasitic wasps. Females lay their eggs in the nests of other wasps, generally large-bodied ground nesting wasps, such as the Eastern Cicada Killer (Sphecius speciosus). Within the nest the Cow-Killer egg hatches and its larva will feed on its unsuspecting roommate, killing it and commandeering the nest.
Eastern Velvet Ants get the unique “cow killer” common name from their venom. The sting of a Cow-Killer is blindingly painful and although not potent enough to kill a cow, nor really any mammal, it certainly feels like it! That’s a fact they advertise far and wide with their bold color pattern. Contrasting patterns of red and black are the universal caution sign of the animal kingdom. This is called aposematic coloration. It’s a signal to predators to “woah-up!” and think before they act. The female Cow-Killer amplifies this effect to the next level, practically embodying a neon skull and crossbones. Her fuzzy fluorescent self exaggerates this coloration as she darts and vibrates across the ground in broad daylight, making her unmissable by anything with eyes. This violent, vibrant, vibrating is intended to trigger a deep-seated danger response in your brain and subsequently get you to steer clear and resist the intrusive thought to grab the aggressively twitching red bug.
In addition to their malevolent aura, they also scream. When handled or harassed, both males and females will rub their abdomen segments together, a process called stridulation, to make a rapid high-pitched squeaking noise to further elevate their warning signal. If that doesn’t work, they’re also heavily armored. The exoskeleton of the Cow-Killer is thick and tight-fitting, like a medieval suit of plate armor. So even if an oblivious or emboldened creature does get a hold of them, they’re far more durable than they appear. This will ideally buy the Cow-Killer enough time to angrily shriek and sting their attacker in the face, in the hopes they get dropped and can live another day.
This week for Flora and Fauna Friday we have a spicy shrub that’s a summer safe haven for pineywoods pollinators, Coastal Sweet Pepperbush (Clethra alnifolia).
Coastal Sweet Pepperbush is found all along the East Coast and throughout the coastal plain of South Carolina. It grows on moist and generally acidic soils, often in partial shade. It’s a small deciduous shrub, growing usually chest to head height, and usually forming thickets. It does especially well in pine flatwoods where soil and light conditions are ideal for it and frequent fires free nutrients for new growth. Its leaves are alternate, fairly large, emerald-green, and widest towards the tip with that tip being pointed and its margin serrate. Its leaves also have diagonal veins that are nearly parallel, giving them a look that resembles Hazel Alder (Alnus serrulata), a shrub found along wetlands and creek banks, and the origin of our Pepperbush’s specific epithet of “alnifolia” or “Alder-leaved”. Coastal Sweet Pepperbush blooms in July and August, peaking between the two months. Each flower is about fingernail-sized, five-petalled, white with orange anthers, and arranged with dozens more flowers into a bottlebrush. These flowers have a pungent, sweet and spicy smell to them that lingers in the air like perfume around the thicket. Flower clusters are produced at the tip of each branch and held upright. Coastal Sweet Pepperbush flowers are a burst of white above the verdant brush that stands out starkly on the summer landscape. They draw in insects from the surrounding landscape and are an important source of pollen and nectar for native pollinators during the dog days of summer. Flowers mature into chains of small dry capsules that shake and scatter their seeds into the breeze. These dry fruits have a resemblance to a string of black peppercorns, and thus gives the “pepperbush” its name. These capsules are held aloft atop the plant through winter, making it an easy shrub to identify from mid-summer onward.
We technically, maybe, possibly, might, perchance, in theory, have two species of Pepperbush here in the Lowcountry. In addition to Coastal Sweet Pepperbush (C. alnifolia), there’s also Downy Sweet Pepperbush (C. tomentosa). Downy Sweet Pepperbush is much the same in appearance and ecology but has a stronger affinity to acidic sites, blooms a skosh later, and has a lot more hair across the plant. Most notably it has a silvery woolen leaf underside, hair along twigs and leaf margins, and shorter flower styles with downy hairs along them. These distinguishing features are somewhat variable across its geographic range but appear consistent within the pineywoods of South Carolina. However, the taxonomic jury is still out on whether Downy Sweet Pepperbush is a separate species or just a variety. So I’ve lumped them together here for the sake of today’s article. But do note, most of my photos are of Downy Sweet Pepperbush (Clethra tomentosa).
This week for Flora and Fauna Friday it’s the vocalist of the valley, the flitter over the floodplain, the Acadian Flycatcher (Empidonax virescens).
The Acadian Flycatcher can be found throughout the eastern United States in the warmer months, including all of South Carolina. They have a strong habitat preference for floodplain forests, stream valleys, river margins, bottomland fringes, and other wet deciduous forests. Most always seen in dim or dappled light, Acadian Flycatchers blend into the forest scenery, sitting perched upon a twig along a void of branches, as they twitch their head in search of prey. They subsist on a diet of primarily insects, snatched on the wing from the stagnant swamp air. Acadian Flycatchers are a mid-sized songbird with a large head and short legs. Their head and back are a dull olive-drab, their wings a grungy ebony-brown, and belly a sour greenish-white. Strongly contrasted pale wing-bars and a thin white eye-ring around a large, dark eye give them their only remarkable features in profile.
However, this feathered fashion of theirs is shared by nearly all of our other “Empid” Flycatchers in the Empidonax genus. This is a cadre of songbirds that is notoriously difficult to distinguish by eye, by both bird watchers and ornithologists alike. We see five species of Empids in South Carolina to include the Yellow-bellied Flycatcher (E. flaviventris), Willow Flycatcher (E. traillii), Alder Flycatcher (E. alnorum), and Least Flycatcher (E. minimus), in addition to the Acadian Flycatcher. Of these five, the Acadian Flycatcher is the only species that hangs around the Lowcountry throughout summer. The other four just pass through during migration and occasionally may nest in the mountainous margin of the State. Yet during migration, if you’re confronted with a mystery Flycatcher, there are still some subtle visual differences between all five. But I won’t delve into those here as we’d be here all day and, thankfully, each species has a different song. The song of the Acadian Flycatcher is a fast, two-note “flee-See!” said sharp and clear with a slight ring to it, starting flat on the first note then rising sharply in pitch through the second. It’s a divining ditty that signals the shoulder of a stream and the whereabouts of wetlands, water under the watchful eyes of a Flycatcher.
This week for Flora and Fauna Friday we have another of our large and lavish lavender legumes, Atlantic Pigeonwings (Clitoria mariana).
Atlantic Pigeonwings is a species of legume found throughout the southeastern United States and all of South Carolina. It’s most abundant on dry, sandy soils and is thus found on barrier islands, high sand ridges on the Sea Islands, and Longleaf Pine savannas on the mainland. Being a legume, it has a leg up in these thin sandy soils through its ability to fix nitrogen. Legumes are able to trade sugars to the symbiotic bacteria living inside their roots, which in turn fix nitrogen from the air. Atlantic Pigeonwings is a perennial vine that grows a small tuberous rhizome underground and a thin, wiry stem above the earth. The vine climbs through twining but rarely reaches above ankle high, more often snaking across the soil as a groundcover. Its leaves are alternate and compound, composed of three simple leaflets. There’d not be much to show for this plant if it wasn’t for it showy flowers.
Atlantic Pigeonwings’ bloom time starts in June, peaks in July, and lasts through August. Its flowers are about an inch long and twice as wide. They have that classic pea-flower form of one large lower petal and two smaller upper petals, which form a hood over the anthers and stigma. The petals are all a pale-lavender in color, with the lower petal possessing a streak of white down the center that’s flanked by bowing brindled bands of a darker purple-mauve. Atlantic Pigeonwings’ flowers are specially shaped to guide Bumble Bees straight to their anthers, forcing them to take a dusting of pollen if they’d like a sip of nectar. However, many butterflies are able to cheat this system, using an elongated proboscis like a silly-straw to steal sips at a distance. One specific butterfly, the Long-tailed Skipper (Urbanus proteus), also hosts on Atlantic Pigeonwings, laying eggs on its leaves and its caterpillars then munching away at the foliage and flowers.
Atlantic Pigeonwings has a very similar looking cousin who also grows across the Southeast, Spurred Butterfly Pea (Centrosema virginianum). I’ve covered that species previously and it differs in a few key ways from today’s Pigeonwings. Spurred Butterfly Pea is more shade tolerant, grows in damper soils, has wider leaves, climbs higher, and has a flower that’s nearly circular and with no purple streaking on the lower petal.
This week for Flora and Fauna Friday it’s the hovering hunter lurking on every wetland’s edge, the Common Green Darner (Anax junius).
The Common Green Darner is an aptly named dragonfly. It’s common, abundant, and widespread. It’s found across all of South Carolina and the whole of the contiguous United States. The Common Green Darner is a big dragonfly, growing to about three inches long. Their thorax is solid Scheele’s-green with their head a more yellowish shade and sporting two huge compound eyes. For some color contrast, in males their abdomen is a brilliant turquoise-blue and, in females, a faded cinnabar-red. Their wings are mainly clear, with a faint wash of amber along the veins and a straw-yellow pterostigma near the tip. The family name “darner” comes from the shape of their abdomen and its cerci, the terminal appendages at the abdomen’s tip. In many Darners, the cerci of both sexes are long and, when at rest, overlap with an “eye of a needle” shape, giving the whole abdomen the silhouette of a darning needle, hence ‘Darners’. Cerci, along with the epiproct in males, are collectively called “claspers”. Males use their claspers to hold onto a female’s neck while mating. The Common Green Darner is unique among our southeastern Darners for laying eggs in tandem. Males continue to cling to the female after mating, even flying in line with her, until she lays her eggs. Eggs are often laid under floating vegetation or debris on the surface of a still pond or freshwater marsh.
The baby dragonflies hatch as nymphs, called naiads. The little naiads are just as voracious of predators as ‘ma and ‘pa, lurking in the murk to ambush unsuspecting prey with their projectile mouths. The naiads will patrol their watery nursery, sometimes for several years, until large enough to eclose into adults. Adult Common Green Darners, like all other dragonflies, are skilled hunters and agile acrobats. They nourish themselves on a steady diet of anything smaller than them that catches their omnidirectional eye in the sky. Darners, unlike most dragonflies, rarely land during the day. Common Green Darners prefer to hover on the wing or course across the water at speed in search of prey.
Common Green Darners are powerful flyers and will travel long distances to find a suitable abode, staking a claim collectively at every suitable pond and puddle in sight. They also perform a multi-generational migration, similar to the Monarch butterfly. Common Green Darners fly north each spring in search of open territory. They start a family there and then pass away. Late that summer or the following year, their offspring emerge and circle back south to escape the cold and hitch their wagon in the sub-tropics. Their grandchildren emerge in fall and repeat the multi-generational circuit the following spring. This allows the species to live a nomadic lifestyle and take advantage of a much wider geographic range, becoming more abundant, staying genetically diverse, but never over-specializing to one specific habitat or eco-region.
This week for Flora and Fauna Friday we have a wildflower that’s a feast for pollinators, Savanna Mountain-Mint (Pycnanthemum flexuosum).
Here in the South Carolina coastal plain, about seven species of Mountain-Mint can be found growing wild. Of those, Savanna Mountain-Mint is by far the most abundant here in the Lowcountry. Most all of our Mountain-Mints follow a similar physical pattern. Their growth is perennial, dying back to the roots in winter and spreading laterally underground all the while. They’re a large wildflower, growing waist to chest-high on oppositely arranged branching stems to create a small bush. Atop that bush will emerge small floral disks studded with white flowers and often perch above a ring of silver-washed leaves. Our subject today, Savanna Mountain-Mint, fits this generic mold well but with a few standout features to distinguish it from its relatives.
Savanna Mountain-Mint is on the smaller side for its genus, reaching up to about hip-high. Its leaves are thin and simple and shrouded in a faint silvery haze of fine hairs. Their stems share that same pale haze and they also bare the trademark square cross-section of the Mint Family, Lamiaceae. This species has a greater proclivity to spread through underground roots into a cluster than other Mountain-Mints, due to its preferred home in the fire prone Longleaf Pine savanna, a habitat where vegetation can be volatile but roots oft run deep. With the onset of summer, Savanna Mountain-Mint will begin to bloom, peaking in early July. The calyx of this species, the cup of leaves beneath each individual flower, produces five long, white points. This gives the flower clusters of Savanna Mountain-Mint an appearance like flattened pincushions. From this cluster emerges the actual flowers, about a quarter-inch wide and white with small magenta dots on their lower lip. Often times, only about a half-dozen flowers are present at a time on any lone cluster, with fresh flowers appearing every few days.
Like most mints, Mountain-Mint flowers are tubular in shape with a bilaterally symmetrical corolla of five petals. Two petals hang above the entrance to the tube and three fan out flat beneath it. This shape corrals pollinators, like a door with an awning and a porch, encouraging them to approach the flower from just one direction. This forces insects to contact an anther or stamen if they want a drink of sweet, sweet nectar, which in turn ups the odds that they’ll pollinate the flower. Savanna Mountain-Mint, and the genus in general, is an exceptional pollinator plant. They are enjoyed by pollinators of all shapes and sizes, from the minutest bee to the broadest of butterflies. Savanna Mountain-Mint is rather drought and heat tolerant for the genus and adapts well to many sandy soils, making it a good addition to native plant gardens here on the Sea Islands.
This week for Flora and Fauna Friday it’s the gray-green window hopper, the Squirrel Treefrog (Hyla squirella).
The Squirrel Treefrog is found throughout the coastal plain of the Southeast and the whole of the South Carolina Lowcountry. It’s the most generalist of our Treefrog species and can be found in most moist forest habitats and across the Sea Islands, even tolerating some brackish conditions. They’re on the smaller side for Treefrogs, at an inch-and-a-quarter long, and range in color from lime-green to mottled khaki-brown to a pale greenish-gray, and everything in between. Thus, they can be a real devil to identify, especially since Squirrel Treefrogs lack any distinctive features. You have to use process of elimination most of the time. If it lacks the white flank strip of the Green Treefrog (H. cinerea), the warty skin of the Cope’s Gray Treefrog (H. chrysoscelis), and the yellow thigh spots of the Pinewoods Treefrog (H. femoralis), then you can be decently sure it’s a Squirrel Treefrog!
Another way to identify them is through their song. The male Squirrel Treefrog’s song is a monotonous string of the phrase “bahk”, a gravelly croak repeated about twice a second. They get the “squirrel” in their common name from their song, which is reminiscent of the scolding calls of an Eastern Gray Squirrel (Sciurus carolinensis). Squirrel Treefrogs are known for their “rain calls”, singing immediately after the onset of rainy weather, wherever they happen to be hanging out. Like all our Treefrogs, they rely on ephemeral wetlands to breed. Places that flood for prolonged periods after heavy rain but dry out during the year, keeping the wetland free of fish and making a perfect nursery for tadpoles.
Squirrel Treefrogs are the most likely amphibian in the Lowcountry to set up shop around your home. About your place they’ll hide from the day’s rays behind shutters, between pots, and up downspouts, only piping up to celebrate a storm cloud. At dusk during the warm months they’ll emerge to chase insects, attracted to porch lights and the amber glow of windows.
This week for Flora and Fauna Friday we spy a native grass just beyond the surf and rising above the turf, Pinewoods Fingergrass (Eustachys petraea).
Pinewoods Fingergrass is native to the southern coast of the United States, from Texas through North Carolina. Here in South Carolina, it’s found in all our coastal counties and throughout our Sea Islands. It thrives on our young marine soils, coarsely sandy and rich in calcium from pulverized shells. I most often encounter it on Barrier Islands in healthy maritime forests, more inland on sandy ridges in the pineywoods, or along the shoulders of limestone roads in either.
Pinewoods Fingergrass is a perennial warm-season grass. It spreads weakly through running stolons into a loose clump but mainly disperses about the landscape through seeds. Its leaves are a soft blue-green and grow upward to about a foot in length. It begins to flower in mid-spring and continues through the end of summer. Its innocuous grass flowers chain together into one-sided comb-like spikes. Often their flower head is comprised of five spikes, lifted upward to two feet on a central stalk. This flower stalk arrangement resembles a hand reaching upwards to the sky and it provided the plant its “fingergrass” common name.
Pinewoods Fingergrass is a hardy native grass and can be a great addition to coastal yards. It does well in both full sun and partial shade. It’s well adapted to our coarse, sandy sea island soils with great drought tolerance and high resistance to saltwater intrusion and salt spray. As a grass, it’s mainly ignored by deer and likely a host plant for several species of our Grass Skipper butterflies. Unlike nonnative turf grasses, Pinewoods Fingergrass spreads sparsely and politely, allowing it to play nicely wildflowers in native plant gardens and alternative lawns, without taking them over.
This week for Flora and Fauna Friday we uncover a hidden gem, the sapphire pendant on the pineywoods, the Indigo Bunting (Passerina cyanea).
In the sweltering heat of the summer savanna, below a bluebird sky, a cascade of double notes catches the ear and draws the eye. A cerulean speck trumpets from a treetop, anointing a pine with a rare drop of blue spilled down from the sky. As you strain your eyes to resolve its form, the drop plummets further from the tree, curving on the wind before it collides with the Earth and sinks within the grassy sea of green that flows across the savanna. As quick as it fell it buoys back into sight. Set on a low bough of a flame charred shrub, a brilliance of blue shines like a sapphire amplified in the sun. A male Indigo Bunting presents in rare form.
The Indigo Bunting is found throughout the eastern United States from spring through fall, but under the summer sun is when they shine. They dwell on the boundary of forest and field, in open woodlands, clear cuts, and fringes of farms. Here in the Lowcountry, the Longleaf Pine savannas are their favorite haunts, a perfect middle ground between woodland and grassland. Indigo Buntings are most often heard before they are seen. Males fly to the tops of the tallest trees and serenade the savanna in bird song. Their song is a distinctive stuttered warble, with every phrase spoken twice before moving to the next. When they decide to drop down to the forest floor to forage, you may be blessed enough to watch one up close. Females are camouflaged, pale-khaki below, faded-chestnut upon the back, and ebony in their wings and tail. Contrastingly, male Indigo Buntings are dyed a deep indigo-blue across almost their entire body. The black between their eyes and their pewter-gray bill and down their flight feathers only serves to compliment the richness of their blue plumage. This blue changes in hue depending on how light hits the bird. This unstable hue is due to this being a structural color. Rather than a pigment dyeing the feathers blue, the microscopic shape of the feathers’ vanes force only blue light to reflect. Meaning the stronger and bluer the light, the bluer the Indigo Bunting glows.
This week for Flora and Fauna Friday it’s the saffron signal of the summer solstice, Golden Canna (Canna flaccida).
Golden Canna is a common plant down in Florida but scarcely scattered on the landscape here in the Lowcountry. It’s a rare sight most anywhere in South Carolina but we’re blessed with a wild patch or two on Edisto Island. It grows in saturated mucky soils in freshwater marshes and is tolerant of submersion during the growing season. Golden Canna is a large perennial wildflower that spreads below the soil through rhizomes. Its leaves are large at over a foot long, tongue-shaped with a pointed tip, yellow green in color, and held upright around its fleshy stem. The foliage grows to just above waist high.
Golden Canna begins to bloom in mid-May and continues through mid-June. Its flowers are hung above the foliage, a frilly folded funnel of pastel-yellow unmistakable as anything else. These flowers attract bees and large butterflies, particularly Swallowtails, to pollinate them. Pollinated flowers mature into seedpods about the size and shape of a starfruit but fuzzy and pale-green. These seedpods dry over time and their skin disintegrates, revealing magazines of hard, round, and black seeds the size and shape of 00 buckshot.
Golden Canna makes for a good wildflower addition to most pond banks and rain gardens. They do best on rich, saturated soils and with plenty of sun. However, they’re frost intolerant. So the subtropical Sea Islands are where they’ll thrive most reliably. They attract pollinators when in bloom, have handsome foliage when not, and that foliage is the larval food for the Brazilian Skipper butterfly (Calpodes ethlius).
We have two non-native Cannas floating around Edisto Island as well, Indian Shot (Canna indica) and Garden Canna (Canna X generalis). Indian Shot has red flowers with narrow petals and broader leaves held more perpendicular to the stem. Garden Canna is a catchall taxa of hybrid plants and thus comes in a hundred different forms. However, it most often has darker, larger foliage. Both can readily be separated from Golden Canna by their seedpods, which are half the size, roughly spherical, and held upright.
