Polystichum Acrostichoides, the Christmas fern, is an evergreen eastern North American woodland fern that slowly forms a fountain-like clump.
Its leathery dark green once-pinnate fronds rise from a short brown-scaled crown, with each narrow pinna bearing a distinctive auricled base.
Fertile fronds narrow in their upper third and carry orderly round sori beneath the reduced pinnae, while silvery scaled croziers emerge in spring.
Grow it in cool humus-rich, well-drained soil in partial or full shade; established plants tolerate some dry shade, but winter waterlogging can cause crown rot.