Sparganium americanum - (image 1 of 5)
Taxonomy
Family: Sparganiaceae
Habitat
Mud or shallow water of marshes, swamps and shores.
Associates
Distribution
Newfoundland and Quebec west to MN, south to FL and LA.
Morphology
Herbaceous perennial to 1 m high. Leaves to 1.2 cm wide and up to 1 m long, usually thin and flat but sometimes weakly keeled; bracts often dilated at the base. Inflorescence simple or branched; flowers small, in globular heads, tepals 2/3 as long as the fruit, dilated at the tip; pistillate heads all axillary and subtended by bracts, 2-4 on the central axis and 1-3 on the branches, all sessile, stigmas and locule 1; stigma 1-1.5 mm; staminate heads 1-5 on the branches, 3-10 on the main axis; anthers and stigma linear. Fruits fusiform achenes, dull, sordid brown, 3-5 mm thick, in globular heads to 2 cm across.
Notes
Flowers late June to August
Wetland indicator: Obligate
The plants were growing on mudflats remaining after a beaver dam was removed.
References
Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of
Northeastern United States
and Adjacent Canada. Second Ed.
The New York Botanical Garden. Bronx, NY
Swink, F. and G. Wilhelm. 1994. Plants of the Chicago Region.
Indiana Academy of Science. The Morton Arboretum. Lisle, Illinois.
Winterringer, Glen S. and Alvin C. Lopinot. 1966. Aquatic Plants of Illinois
Illinois State Museum and Illinois Dept. of Conservation
Michael Hough © 2009 |