Narrow Leaf Arrowhead

Herbs, perennial, to 170 cm, mostly of fresh waters, some plants stranded along shore; rhizomes absent; stolons present; corms present. Leaves submersed or floating, rarely emersed; submersed phyllodial, flattened, 30--250 ´ 0.1--1.5 cm; floating with petiole flattened, to 40 cm, blade linear-ovate to ovate, rarely sagittate, to 3.5 ´ 0.5 cm; emersed with petiole 5--10 cm, blade linear-ovate to ovate, rarely hastate to sagittate, to 4 ´ 0.5 cm; stranded plants usually with expanded leaf blades. Inflorescences racemes, rarely panicles, of 4--10 whorls, floating to slightly emersed, 15--25 ´ 5--15 cm; peduncles 10--200 cm; bracts connate more than ¼ total length, lanceolate, 110 mm, delicate, not papillose; fruiting pedicels spreading to recurved, cylindric, 1.5--4.5 cm. Flowers to 3 cm diam.; sepals spreading in staminate, erect in pistillate, enclosing flower or fruiting head; filaments dilated, ± equaling anthers, glabrous; pistillate pedicellate, without ring of sterile stamens. Fruiting heads 0.7--1 cm diam.; achenes obovoid, abaxially keeled, 5 ´ 2.5 mm, beaked; faces not tuberculate, wings 0--3, ± entire, glands 0--1; beak lateral, erect, 1 mm. 2n = 22.

Ala., Conn., Fla., Ga., Maine, Mass., N.J., N.Y., N.C., Pa., R.I., S.C., Va.

Flowering summer--fall.

Shallow, swift waters or deep streams in northern portion of range; ponds, lakes, drainage canals, and swamps in southern portion of range; 0--100m.

Sagittaria stagnorum Small; S. subulata (Linnaeus) Buchenau var. gracillima (S. Watson) J. G. Smith

Sagittaria filiformis J. G. Smith, Rep. Mo. Bot
Gard. 6 : 46. 1895.
Plants submerged, not greatly elongate ; leaves mere bladeless phyllodia with slender or filiform tips from thicker bases, 1-6 dm. long or rarely as long as the scape ; scapes slender, 6-12 dm. long, often branching from the lower whorls; bracts lanceolate, 3-5 mm. long, acuminate; pedicels slender or filiform, those of the lower whorls 1-4 cm. long; whorls remote, the flowers staminate except 1 or 2 flowers of the lower whorl ; sepals ovate, 2-3 mm. long, obtuse; corolla white, about 2 cm. broad; fruit-heads 6-7 mm. in diameter; achenes 1.5 mm. long, with about 6 crests, the beak lateral, upwardly curved.
Type locality : Dog River, Mobile County, Alabama.
Distribution : Florida and Alabama ; apparently also in the Carolinas.

Sagittaria filiformis, the threadleaf arrowhead, is an aquatic plant species native to the eastern United States, from Maine south to Florida and Alabama. it occurs in flowing streams in the northern part of its range, but more stagnant waters such as marshes and swamps in the South.

Sagittaria filiformis is a perennial herb up to 170 cm tall. Some leaves are thread-like, entirely underwater, but others are narrowly ovate or lanceolate and floating on the surface.