Sagittaria graminea |
Sagittaria engelmanniana |
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grass-leaf arrowhead, grassy arrowhead, sagittaire a feuilles de graminees |
acid-water arrowhead, Engelmann's arrowhead |
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Habit | Herbs, perennial, to 100 cm; rhizomes coarse; stolons absent; corms absent. | Herbs, perennial, to 70 cm; rhizomes absent; stolons present; corms present. | ||||||||
Leaves | submersed or emersed; submersed leaves phyllodial, angled abaxially, flattened adaxially, 6.4–35 × 0.5–4 cm; emersed with petiole triangular, 6.5–17 cm, blade linear to linear-oblanceolate, 2.5–17.4 × 0.2–4 cm. |
emersed; petiole triangular, 10–40 cm; blade sagittate, 4.5–10 × 0.2–2 cm, basal lobes ± equal to remainder of blade. |
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Inflorescences | racemes or panicles, of 1–12 whorls, emersed, 2.5–21 × 1–8 cm; peduncles 6.5–29.7 cm; bracts connate more than to equal to ¼ total length, broadly subulate to lanceolate, 20–50 mm, coarse, not papillose; fruiting pedicels spreading, cylindric, 0.5–5 cm. |
racemes, of 2–4 whorls, emersed, 5–14 × 2–4 cm; peduncles 20–38 cm; bracts distinct or if connate, then less than ¼ total length, lanceolate, 5–25 mm, not papillose; fruiting pedicels spreading, cylindric, 1.5–3.5 cm. |
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Flowers | to 2.3 cm diam.; sepals recurved to spreading, not enclosing flower; filaments dilated, shorter than anthers, pubescent; pistillate flowers pedicellate, without ring of sterile stamens. |
to 30 mm diam.; sepals recurved to spreading, not enclosing flower or fruiting head; filaments linear, longer than to equal length of anther, glabrous; pistillate pedicellate, without ring of sterile stamens. |
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Fruiting | heads 0.6–1.5 cm diam.; achenes oblanceoloid, without abaxial keel, 1.5–2.8 × 1.1–1.5 mm, beaked; faces not tuberculate, abaxial wings 0–1, ± entire, glands 1–2; beak lateral, erect, 0.2 mm. |
heads 1–1.8 cm diam.; achenes cuneate to obovoid, without abaxial keel, 2.4–4 × 1.5–3.8 mm, beaked; faces not tuberculate, wings 1–3, ± entire, glands 1–2; beak lateral, obliquely ascending, (0.7–)1–2.1 mm. |
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2n | = 22. |
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Sagittaria graminea |
Sagittaria engelmanniana |
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Phenology | Flowering late spring–summer (Jun–Sep). | |||||||||
Habitat | Acid waters of ponds, lakes, bogs, and streams | |||||||||
Elevation | 0–1100 m (0–3600 ft) | |||||||||
Distribution |
AL; AR; CT; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WA; WI; WV; NB; NF; NS; ON; PE; QC; West Indies (Cuba)
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AL; CT; DE; FL; GA; MA; MD; MS; NC; NJ; NY; PA; RI; SC; VA; ON
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Discussion | Seven varieties of Sagittaria graminea have been recognized, i.e., var. graminea, var. platyphylla Engelmann, var. teres (S. Watson) Bogin, var. weatherbiana Fernald, var. cristata (Engelmann) Bogin, var. chapmanii J. G. Smith, and var. macrocarpa (J. G. Smith) Bogin (C. Bogin 1955). We accept only one infraspecific rank, i.e., subspecies. Consequently, we have made the appropriate combinations. We accept all of the taxa accepted by Bogin at the varietal level. At specific level we accept Bogin’s var. platyphylla, var. teres, and var. cristata and at subspecific level his var. graminea, var. chapmanii, and var. weatherbiana. Sagittaria graminea var. macrocarpa actually is synonymous with var. graminea (E. O. Beal 1960b). We therefore are following Beal in recognizing var. macrocarpa sensu Bogin as S. fasciculata. We also accept var. platyphylla, var. teres, and var. cristata at the specific level, leaving only three subspecies. These subspecies can be separated by the branching of the inflorescence and the length of pistillate pedicels. Subspecies 3 (3 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 22. | FNA vol. 22. | ||||||||
Parent taxa | ||||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Name authority | Michaux: Flora Boreali-Americana 2: 190. (1803) | J. G. Smith: Memoirs of the Torrey Botanical Club 5: 25. (1894) | ||||||||
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