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DescriptionThis deciduous fern consists of a single sterile leaf about 4-8' long and 5-10' across on an erect basal stalk about 2-6' tall; this leaf is sessile. On some ferns, a second fertile leaf is produced on a long stalk that originates from the base of the sterile leaf. The basal stalk is light green to dark red, glabrous, terete, rather succulent, and stout. The sterile leaf is ascending or horizontal to the ground. It is light to medium green, deltate in outline, bipinnate-pinnatifid, and glabrous. The sterile leaf is pinnately divided into 5-12 pairs of leaflets that are individually deltate-ovate to lanceolate-oblong in outline; each leaflet is pinnately divided with up to 12 pairs of subleaflets that are individually oblong-lanceolate to lanceolate in outline. Each subleaflet is pinnatifid and coarsely dentate along its margins, dividing shallowly to deeply into several pairs of lateral lobes that are irregularly shaped. The stalk of the fertile leaf is 3-6' long, light green, terete, slightly succulent, and glabrous. At its apex, there is a glabrous fertile leaf about 3-6' long and about one-half as much across; its structure is bipinnate to pinnate. The leaflets and subleaflets are stalk-like in shape with sessile sporangia (spore-boring structures) along their sides; they are initially light green, but become brown at maturity. Individual sporangia are globoid in shape and 1 mm. across or less; they are initially light green, but become yellow and finally brown when their spores are released. A fertile leaf begins to develop before the sterile leaf has fully unfolded during the late spring. Spores are released from the fertile leaf during the summer. They are distributed by the wind. The root system is fibrous and fleshy. Occasionally, clonal offsets are produced.