keys to the vascular plants of east texas - Botanical Research ...

348 DRYOPTERIDACEAE/NEPHROLEPIS
scaly at base; leaves evergreen; leaf blades 1-pinnate-pinnatifid, lanceolate, 25–120 cm long, the
basal pinnae much reduced; fertile pinnae in distal 1/2 of leaf blade; segments of fertile pinnae
distinctly narrower than those of sterile pinnae, often more widely spaced, and sometimes contracted
at base. Swamps and wet woods; Hardin (Watson, s.n. 1971, TEX—first confirmed collection
for TX); Correll 1972a), Jasper (BRIT, TEX), and Polk (TEX) cos. in the Pineywoods. Correll
(1956) said, “This species was reported by Reverchon (1903) as having been collected by J.M.
Fetherolf in Newton County in the Timber Belt. It was also reported from Texas by Cory and
Parks (1937). I have not seen any specimens of this species west of East Baton Rouge Parish,
Louisiana.” Correll (1972a) subsequently reported it for TX. This diploid species is endemic to
the se U.S. (Montgomery & Wagner 1993), most collections being from the deep southeast with
outliers in AR, LA, and TX. Sporulating spring–fall. [Aspidium ludovicianum Kunze;
Thelypteris ludoviciana of authors] This species is reported to cross with D. celsa resulting in
sterile hybrids (Werth et al. 1988; Montgomery & Wagner 1993). (TOES 1993: IV) �
NEPHROLEPIS Schott BOSTON FERN, SWORD FERN
AA genus of 25–30 species widespread in tropical areas (Nauman 1993c). Nephrolepis is sometimes
placed in the Davalliaceae or Nephrolepidaceae (e.g., Kramer 1990d; Nauman et al. 2000).
(Greek: nephros, kidney, and lepis, scale, in reference to the shape of the indusium)
REFERENCES: Nauman 1981, 1993c; Schneider & Carlquist 1999b.
Nephrolepis exaltata (L.) Schott, (very tall), SWORD FERN, BOSTON SWORD FERN, WILD BOSTON
FERN. Stems (rhizomes) short, � erect, with wiry, widely creeping stolons; leaves monomorphic,
evergreen, clustered, 1-pinnate, usually 0.4–1.5 m long, the blades linear-lanceolate; sori roundish,
somewhat closer to margin than to midvein of pinnae, the indusia � orbicular-reniform.
Escaped, persisting and spreading in yard in Highland Park, Dallas Co. (R. O’Kennon, pers. obs.),
also Orange (BRIT), Nacogdoches (TAES), and Henderson (Turner et al. 2003) cos.; naturalized
in several sites in East TX and on the Edwards Plateau; native to FL, the West Indies, and scattered
Pacific Islands. Sporulating throughout most of the year (Correll 1956). This species is terrestrial
or more often epiphytic in its native habitat. It is a commonly cultivated (particularly
indoors) and commercially important fern with many cultivars including cv. ‘Bostoniensis’
(BOSTON FERN) and the locally developed DALLAS JEWEL FERN, commonly known as the
DALLAS FERN. There is debate over the origin of the name BOSTON FERN, but it apparently originated
in the late 1800s or early 1900s when plants of a particular form of N. exaltata became
popular in nurseries in and around Boston, MA (Benedict 1916).
ONOCLEA L. SENSITIVE FERN
AA monotypic genus of n temperate areas (Johnson 1993b); sometimes cultivated as an ornamental.
(Greek: onos, vessel, and cleisto, closed, in reference to the “segments of the fertile frond
that roll up into hard, bead-like structures enclosing the sori”—Moran 2004)
REFERENCES: Lloyd 1971; Beitel et al. 1981; Rothwell & Stocky 1991; Johnson 1993b.
Onoclea sensibilis L., (sensitive), SENSITIVE FERN, BEAD FERN. Stems (rhizomes) creeping; leaves
conspicuously dimorphic, of 2 very different types, scattered along the rhizome, erect, glabrous;
sterile leaves to ca. 1(–1.3) m tall, thin herbaceous, deciduous, broadly triangular to ovate in outline,
deeply pinnatifid with the pinnae few, the pinnae subopposite (especially the lowermost),
undulate to irregularly deeply lobed, the margins entire, the veins reticulate and forming a series
of linear to oblong areoles along the midvein (= costa), the rachis winged; fertile leaves persistent
over winter, 2-pinnate, the blades greatly reduced, the ultimate blade segments (= smallest
subdivisions of blade) rolled into globular, berry-like or bead-like structures concealing the
sori, the whole fertile leaf superficially resembling a narrow panicle of small round fruits.
Swamps, low woods, and wet areas; Pineywoods and n edge of Gulf Prairies and Marshes w
through Post Oak Savannah to Milam, Upshur (BRIT), Red River, Henderson, Limestone, Falls