FERTILE AND STERILE FRONDS LEAF-LIKE
45. EVERGREEN WOOD FERN. MARGINAL SHIELD FERN
Aspidium marginale (Dryopteris marginalis)
Canada to Alabama, in rocky woods. A few inches to three feet high, with more or less chaffy stalks having shining scales.
Fronds.—Ovate-oblong, smooth, thick, somewhat leathery, once or twice-pinnate; pinnæ lance-shaped or triangular-ovate, tapering at the end, cut into pinnules; pinnules oblong, entire, or toothed; fruit-dots large, round, close to the margin; indusium large, convex, persistent.
Above the black leaf-mould in our rocky northern woods rise the firm, graceful crowns formed by the blue-green fronds of the Evergreen Wood Fern. The plant bears a family likeness to the Crested Shield Fern, but its conspicuously marginal fruit-dots identify it at sight.
It is interesting to read that it comes "nearer being a tree-fern than any other of our species, the caudex covered by the bases of fronds of previous seasons, sometimes resting on bare rocks for four or five inches without roots or fronds" (see Eaton, p. 70). This peculiarity in the plant's growth is often striking and certainly suggests the tree-ferns of the green-house.
Frequently in this species I notice what is more or less common to nearly all ferns, the exquisite contrast in the different shades of green worn by the younger and older fronds and the charming effect produced when the deep green of the centre of a frond shades away in the most delicate manner toward its apex and the tips of its pinnules.
As its English title signifies, the Evergreen Wood