Americanized Eurasian Water Milfoil Gardens Away From Fresh Water

Summary: Americanized Eurasian water milfoil gardens in confined or courtyard fountains, ponds and pools resist ravaging irrigated lands and irrigation systems.

Eurasian water milfoil (Myriophyllum spicatum): Alison Fox, University of Florida, Bugwood.org, CC BY 3.0 United States, via Forestry Images

Americanized Eurasian water milfoil gardens adjust dissolved oxygen levels and water flow rates downward, advance through drainage ditches, irrigated fields, irrigation canals and waterways and assume dominance by aggressive growth and reproduction.

Eurasian water milfoil and its fellow weedy members in the Haloragaceae family of water milfoil aquatic herbs, shrubs and trees bully water quality and water recreation. Threatened crop yields, species diversity and waterway health call up government-enacted weed sanctions against Brazilian, Eurasian and two-leaf water milfoils in Connecticut, Maine, Massachusetts and Vermont. Alberta and Saskatchewan and Colorado, Florida, Idaho, Montana, Nevada, New Mexico, North Carolina, Oregon, South Carolina, South Dakota and Texas describe Eurasian water milfoil as weedy.

The Alabama and the Washington state legislatures enact weed sanctions against non-native Brazilian and Eurasian water milfoils but not against eastern North America's two-leaf water milfoil.

Native European homelands and scientific research settings furnish glimpses of the seedling stage that rarely flourishes anywhere in nature in Canada, Mexico and the United States.

Eurasian water milfoil, commonly named spiked water milfoil, gets featherlike, three- to four-whorled, 0.39- to 1.38-inch- (1- to 3.5-centimeter-) long foliage gathered oppositely around multi-branching stems. Whorls have 28 to 48 0.24- to 0.47-inch- (6- to 12-millimeter-) long segments, contrasted with native, similar-looking northern water milfoil's (Myriophyllum sibiricum) 12 to 22 threads. Eurasian water milfoil foliage is submerged, and its July- through October-blooming flowers emergent, whereas Brazilian and two-leafed water milfoils include four-to six-whorled emergent and submerged leaves.

Emergent-flowering Americanized Eurasian water milfoil gardens jumble Brazilian water milfoil's white to transparent solitary flowers with Eurasian water milfoil's wine-red, and two-leaf water milfoil's red-green, spikes.

Flower-clustered, terminal, unbranched, 1.97- to 7.87-inch- (5- to 20-centimeter-) long inflorescences called spikes keep buoyant, pink, succulent, thick stalks vertical before, and horizontal during, seed releases.

Three- to 10-whorled female, imperfect, lower, regular flowers lose their four red petals and four sepals, but not their pistil, upon opening for perennial bloom times. Four-whorled imperfect, male, regular, upper flowers maintain eight stamens and, until floral openings move all eight permanently from their spikes, four sepals and four wine-red petals. Hormones, nutrients from roots and underground stems called rhizomes and photosynthates in 39.37-foot- (12-meter-) long stems nudge spikes into fruiting globelike nuts with four single-seeded sections.

Nuts offer Americanized Eurasian water milfoil gardens round to fan-angled, rough seeds 0.09 to 0.12 inches (2.5 to 3 millimeters) in diameter and with sharp projections.

Stems with female spikes proffer Eurasian water milfoil, binomialized Myriophyllum spicatum (many-leafed spikes), 12 to 40 seeds with seven-year dormancies, seven-year dry-storage viabilities and 24-hour buoyancies.

Rooting buds from leaf-to-stem attachment angles and from overwintering whorls, fragments from roots and stems and rhizomes from leaf-to-stem attachment nodes qualify as additional reproduction means. Independent plants result from buds, rhizomes and rooted, 3.94- to 7.87-inch- (10- to 20-centimeter-) long fragments in water temperatures above 50 degrees Fahrenheit (10 degrees Celsius). Eurasian water milfoil, described in 1753 by Swedish botanist Carl Linnaeus (May 23, 1707-Jan. 10, 1778), starts up, from fragments, 80-plus independent plants within two months.

Americanized Eurasian water milfoil gardens trample irrigated lands and water bodies least when tethered to indoor and outdoor courtyard freshwater and saltwater fountains, ponds and pools.

dense canopy of Eurasian water milfoil on surface of Cayuga Lake, central New York: Robert L. Johnson, Cornell University, Bugwood. org, CC BY 3.0 United States, 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:

Eurasian water milfoil (Myriophyllum spicatum): Alison Fox, University of Florida, Bugwood.org, CC BY 3.0 United States, via Forestry Images @ http://www.forestryimages.org/browse/detail.cfm?imgnum=1624031

dense canopy of Eurasian water milfoil on surface of Cayuga Lake, central New York: Robert L. Johnson, Cornell University, Bugwood. org, CC BY 3.0 United States, via Forestry Images @ http://www.forestryimages.org/browse/detail.cfm?imgnum=0002002

For further information:

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

Linnaeus, Carl. 1753. "1. Myriophyllum spicatum." Species Plantarum, vol. II: 992. Holmiae [Stockholm, Sweden]: Laurentii Salvii [Laurentius Salvius].
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/359013

"Myriophyllum spicatum L." Tropicos® > Name Search.
Available @ http://www.tropicos.org/Name/15000007

Weakley, Alan S.; and 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.

Wood, Marcia. March 1999. "Foiling Watermilfoil." Agricultural Research, vol. 47, no. 3: 16-17.
Available @ https://agresearchmag.ars.usda.gov/1999/mar/foil