Americanized Brazilian Waterweed Gardens Away From Waterways

Summary: Americanized Brazilian waterweed gardens handle low-light fountains, ponds and pools and murky ditches away from boaters, fishers and swimmers.

Brazilian waterweed (Egeria densa) foliage: Kristian Peters (Fabelfroh), CC BY SA 3.0, via Wikimedia Commons

Americanized Brazilian waterweed gardens alter dissolved oxygen levels and water flow rates, assemble into dense, floating, large mats, assist trapped sediment accumulation and attack aquatic native vegetation, irrigated lands and irrigation systems.

Native and non-native, related weedy herbs in the Hydrocharitaceae family of aquatic freshwater and marine herbaceous waterweeds behave similarly in Canada, Mexico and the United States. State governments in the United States call non-native curly waterweed, duck lettuce, European frogbit, hydrilla and water soldiers weeds for challenging species diversity and water quality. The California state government delivers weed sanctions against native American spongeplant even though no North American legislation describes as weedy native Canadian waterweed or water celery.

Brazilian waterweed, aquatic herbaceous perennial native to Argentina and Brazil, endures similar government-enacted weed designations in Alabama, Connecticut, Maine, Massachusetts, Oregon, South Carolina, Vermont and Washington.

Hydrilla, weedy relative with two small embryonic leaves, called cotyledons, on 0.24-inch- (6-millimeter-) long stems, furnishes an indication of Brazilian, Canada and curly waterweed seedling looks.

Brazilian, Canada and curly waterweeds give glimpses of seedling looks in research settings and, in the first and third cases, South American and South African homelands. Mature Brazilian waterweed, unlike Canadian waterweed's three-whorled leaves and hydrilla's three- to eight-whorled leaves, has crowded, dense, three-whorled upper foliage and four- to eight-whorled lower foliage. It is linear to lance-shaped, 0.39- to 1.58-inch- (1- to 4-centimeter-) long and 0.08- to 0.19-inch- (2- to 5-millimeter-) wide, with fine-toothed margins and tapered points.

American spongeplant's green-white to yellow, curly waterweed's pink-white, duck lettuce's pink- to violet-white and hydrilla's red colors join July- to August-blooming, white-flowering Americanized Brazilian waterweed gardens.

Brazilian waterweed, commonly named anacharis, Argentine elodea, Brazilian elodea, common waterweed, dense-leaved elodea, ditch moss, South American waterweed and water thyme, keeps its oldest flowers tiptop.

Leaf-to-stem attachment angles called axils, on 0.39- to 3.15-inch- (1- to 8-centimeter-) long stalks, launch emergent, male-flowered, showy white inflorescences called cymes horizontally onto water surfaces. Leaflike, two- to five-flowered, 0.29- to 0.47-inch- (7.5- to 12-millimeter-) long spathes maintain every cyme, whose clusters mingle 0.59- to 0.79-inch- (15- to 20-millimeter-) wide flowers. Male-only flowers need three green sepals, three 0.19- to 0.43-inch- (5- to 11-millimeter-) long, 0.24- to 0.35-inch- (6- to 9-millimeter-) wide petals and nine yellow stamens.

Americanized Brazilian waterweed gardens never obtain the perfect flower's green petals, pistil, white, 0.19- to 0.32-inch (5- to 8-millimeter-) long petals and red to yellow stamens.

Dry, explosive, transparent, 0.28- to 0.59-inch- (7- to 15-millimeter-) long, 0.12- to 0.24-inch- (3- to 6-millimeter-) wide capsules produce spindle-shaped to elliptical seeds in native habitats.

Germinating bumpy, viable, 0.19- to 0.32-inch- (5- to 8-millimeter-) long, 0.08-inch- (2-millimeter-) wide, seed with 0.12- to 0.16-inch- (3- to 4-millimeter-) long beaks qualifies as unknowns. Brazilian waterweed roots from double leaf-to-stem attachment nodes on fragmented 19.68-foot- (6-meter-) long stems 0.04 to 0.12 inches (1 to 3 millimeters) in diameter in spring. Brazilian waterweed, described by French botanist Jules Émiles Planchon (March 21, 1823-April 1, 1888) and named Egeria densa (crowded nymph), rarely seeds outside its native habitats.

Seeding trails vegetative offshoots in Americanized Brazilian waterweed gardens and in native homelands where low-lit, murky waters team six times as many male to female waterweeds.

Brazilian waterweed (Egeria densa) flower: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org, CC BY 3.0, via Forestry Images

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Brazilian waterweed (Egeria densa) foliage: Kristian Peters (Fabelfroh), CC BY SA 3.0, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Egeria_densa.jpeg

Brazilian waterweed (Egeria densa) flower: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org, CC BY 3.0, via Forestry Images @ http://www.forestryimages.org/browse/detail.cfm?imgnum=5447179

For further information:

Dickinson, Richard; and Royer, France. 2014. Weeds of North America. Chicago IL; London, England: The University of Chicago Press.

"Egeria densa Planch." Tropicos® > Name Search.
Available @ http://www.tropicos.org/Name/16100033

Planchon, Jules Émile. 1849. "Sp. 1. Egeria densa, Planch." Annales des Sciences Naturelles. Troisième série. Botanique. Tome onzième: 80. Paris, France: Victor Masson.
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/47175182

Weakley, Alan S.; Ludwig, J. Christopher; and Townsend, John F. 2012. Flora of Virginia. Edited by Bland Crowder. Fort Worth TX: BRIT Press, Botanical Research Institute of Texas.