Northern Prairie Wildlife Research Center
Aquatic and Wetland Vascular Plants of the Northern Great Plains
51. Alismataceae, the Water Plantain Family
3. Sagittaria L. -- Arrowhead, duck potato
2. Sagittaria calycina Engelm.
Dwarf to large emergent annual 1-10 dm tall, lacking rhizomes and tubers. Leaves
with terete, spongy-thickened petioles, erect to spreading; emersed blades
sagittate to hastate or earlier ones elliptic-ovate, (1)3-40 cm long, (0.5)2-25
cm wide, the basal lobes much shorter to longer than the terminal lobe. Inflorescence
ultimately leaning or procumbent, the scape terete and spongy-thickened; bracts
membranous, short and broadly rounded at lower nodes, longer and acute to acuminate
upward, 3-10 mm long; pedicels of fruiting heads inflated, 0.5-5 cm long,
recurved in fruit, those of upper male flowers slender. Lower flowers
female or perfect (with a single whorl of stamens), upper ones perfect
or more often male; sepals broad and obtuse, 5-12 mm long, reflexed in
flower but soon appressed to the head of developing fruits and remaining so
on mature heads; petals white with a yellow base, usually not much exceeding
the sepals; filaments roughened with minute hairs. Fruiting heads
eventually nodding, to 2 cm across, convex to somewhat flattened apically; achenes
2-3 mm long, about equally winged dorsally and ventrally, usually with a prominent
resin duct curving over the faces; beak horizontal or oblique, 0.2-0.6
mm long. Jul--Sep. Mud or shallow water of ponds, marshes and drying pools;
sporadic and local in occurrence from the s half of SD through NE; (OH and MI
to SD, s to VA, TN, LA, TX, NM, CA and into Mex.). S. montividensis Cham.
& Schlect. subsp. calycinus (Engelm.) Bogin.
Previous Section -- Sagittaria brevirostra Mack.
Return to Family -- Alismataceae -
The Water Plantain Family
Next Section -- Sagittaria cuneata Sheld.