Typha domingensis Pers., southern cattail. Perennial herb, emergent aquatic or in wet mud, evergreen, clonal forming dense monospecific colonies, rhizomatous, fibrous–rooted, unbranched above base, erect, 140—350+ cm tall; monoecious; shoots vegetative or fertile shoots in clones, leafy from base to ca. 3/4 height, with 1—3 ascending basal leaves without blade or with a diminutive blade and also 8—11+ erect to ascending cauline leaves having blades, glabrous, not glaucous, bases of leaves conspicuously slippery mucilaginous when severed from rhizome; rhizome horizontal, cylindric, > 7 mm diameter, with airy, spongy soft tissue (aerenchyma) enclosing vascular cylinder and in center, with tuberous swellings below shoots, the swellings spheroid to irregularly shaped, to 25—50 mm thick, solid.
Stems elliptic–cylindric, hidden by leaf sheaths and white, internodes condensed (basal leaves) to 240 mm long (cauline leaves), smooth.
Leaves alternate distichous, simple and sheathing; sheath open, 18—33 mm long (basal leaves) to 300—1000+ mm long (cauline leaves), initially white becoming greenish where exposed, membranous on margins, the margins free on lower leaves or overlapping most of length of upper leaves, tapering or curved approaching blade or sometimes lobed at top (typically without auricles), with mucilage glands on inner surface, the mucilage glands narrowly oblong to elliptic or linear, initially colorless in fresh material aging brown or orange–brown; ligule absent; blade strap–shaped (wide–linear to narrowly oblong), 320—2600+ × 5—23 mm, 1—3 upper leaves > inflorescence, tough, entire and translucent on margins, blunt–acute at tip gradually tapered starting 150—200 mm from tip, parallel–veined, dull, smooth, with mucilage glands on lower 10—20 mm of concealed upper surface at base, in ×–section crescent–shaped at base changing to inflated and 1–convex (changing to 2–convex lens–shaped on extremely long leaves) and then to flat on portion tapered to tip, inflated portions spongy with conspicuous, longitudinal, air–filled chambers having thin diaphragms (aerenchyma).
Inflorescence unisexual “spikes” (spikelike), on terminal stalk, each stalk erect with fertile portion 350—600+ mm long having 1(—2 ± contiguous) pistillate spikes having dense and tightly packed pistillate flowers and sterile flowers (lower inflorescence) and with 1 terminal spike of densely packed staminate flowers, unisexual spikes 0—15 mm apart (interrupted), each with thousands of flowers; peduncle stemlike, cylindric, to 6 × 8 mm diameter, tough, green, smooth, glabrous; bract subtending each unisexual spike present or abscised before anthesis; bractlets subtending stalked flower 0—several; pedicel present.
Staminate inflorescence cylindric thick at base and tapered to tip, at anthesis (60—)140—220(—350) × 8.5—11.5 mm, yellow ochre to tan–colored aging darker, flowers abscising leaving roughened axis above pistillate spike; bractlet scalelike and flattened filamentous, 3—4 mm long and crooked, pale straw–colored at base to glossy orange–brown at tip, lanceolate–acuminate at tip or asymmetrically 2—3–forked; pedicel short.
Staminate flower perianth absent; stamens 2—4; filaments threadlike, 3—3.7 mm long including fused as erect axis 1—3.5 mm long, white, flexible; anthers basifixed, dithecal, linear with a swollen tip (connective), 1.4—2.5 mm long, yellow with connective greenish and orangey, longitudinally dehiscent; pollen of individual grains, light yellow, copious, dry.
Pistillate inflorescence evenly cylindric, at anthesis 135—240 × 7—17 mm increasing to 15—25 mm diameter in fruit, cinnamon or almond brown, suedelike, oblique with longitudinal groove at base on shorter side, with clusters of pistillate flowers arising from papillae (compound pedicels), sterile flowers not evenly distributed; bractlets subtending or fused to base of pistillate flowers, threadlike but commonly expanded at ± lanceolate tip, 2.5—3.6 mm long, pale straw–colored, the tip above flowers, acuminate and curved, 0.6 × 0.1—0.2 mm, cinnamon brown.
Pistillate flower± radial, stalked (stipe), the stipe ca. 0.8 mm long, with a whorl of fine hairs at base, the hairs 2—2.5 mm long increasing in fruit, whitish; pistil = ovary atop a stipe, lanceoloid to ellipsoid, ca. 0.5 × 0.2 mm, pale green to transparent, 1–chambered with 1 ovule; style 1—2 mm long, pale green or white at base to arched and cinnamon brown at tip; stigma narrowly lanceolate with acuminate tip (resembling tip of bractlet), cinnamon brown. Sterile flower (carpodium)
2.2—2.5 mm long, stalked (stipe), stipe with 2(—4) whorls of fine hairs along stipe and having a swollen sterile ovary at tip, the hairs fine, ca. 1.8 mm long (lower whorl) or 1 mm long (upper whorl) and slightly exceeding pistil; stamens absent; pistil 1, with sterile ovary, obovoid, ca. 0.7 × 0.35 mm, light green, papillate on top, abortive style < 0.2 mm long.
Fruit follicle, on stipe having whorls of many fine hairs, dispersal unit 8—9 mm long, wind–dispersed or floating on water, in water splitting longitudinally along 1 edge, 1–seeded, follicle fusiform.
A. C. Gibson