Dryopteris ludoviciana, the southern shield fern, is a bold, glossy evergreen native to the wet woodlands of the American South. The species epithet ludoviciana means "of Louisiana," a nod to the swampy bottomlands, blackwater hammocks, and shaded seeps where the fern grows wild, from Florida west to Texas and north through the Carolinas.
Dryopteris ×australis is a fern that cannot, strictly speaking, reproduce, and is all the more vigorous for the lack. This is a natural hybrid, thrown wherever two Southern wood ferns grow within a spore’s reach of one another: the log fern, Dryopteris celsa, and the southern wood fern, Dryopteris ludoviciana. The cross comes out sterile, setting spores that never amount to anything, so the fern cannot seed itself across a bed the way a large fern usually will. Every plant in cultivation traces back by division to a wild clump found somewhere between Virginia and Louisiana, the greatest number of them in Alabama.