This week for Flora and Fauna Friday is the Earth’s veil ennewed on each morning dew, the Southern Dawnflower (Stylisma humistrata).
Here in South Carolina we have four species of Dawnflower and, in the Lowcountry, two are abundant: Southern Dawnflower (S. humistrata) and Coastalplain Dawnflower (S. patens). These two local species are very similar in appearance and preferred habitats. However, Southern Dawnflower is what you’ll find on and around Edisto Island and thus our subject du jour. Coastalplain Dawnflower is more abundant in the Sandhills and up the coast from Charleston, and is distinctly more hairy on its sepals beneath the flower and has thinner leaves on average, if you care to hunt for it afield.
Southern Dawnflower is a low-growing vine found on dry, sandy soils throughout the Southeast. It is best adapted for sand barrens, dry roadsides, and Longleaf Pine Savannas where the sun is strong and hot and where frequent fire or other disturbance keeps soils open and light competition low. Southern Dawnflower’s specific epithet of “humistrata” deftly translates to “layered upon the earth”. This plant creeps as a groundcover across the open soil, intervening and overlapping the grasses and forbs sparsely eking out a living around it. Its vines are thin, wiry, and straight and may extend for several feet in multiple directions. Its leaves are alternate, oval-shaped, lightly crinkled with indented veins, and colored a gentle pastel green. Dawnflowers are easily overlooked, almost a hidden member of our local flora.
Yet come June through July, Southern Dawnflower bursts into view like the crack of dawn. White funnels of flowers fling open each sunrise in sheets across the scene. Each bloom blinding in its purity, reflecting and refracting the sharp morning rays hand in hand with the thick wash of dew drops settled upon and smothering the Sea Islands. Dawnflowers are members of the Morning-Glory family, Convolvulaceae, and share many of their common traits. Like other Morning-Glories, Dawnflower’s flowers have fused petals forming a unified cone. These flowers are pure, solid white and about three-quarters of an inch in breadth and depth. These flowers are magnetic for pollinators and a wonderful source of pollen and nectar for native bees, wasps, and butterflies during the dawning dog days of summer. Southern Dawnflower makes an excellent alternative groundcover for sunny lawns on barren sandy soils. When and where it’s too tough for turf to tolerate, Dawnflower perseveres and greets the day at the end of May bright eyed and bushy tailed.
