Americanized Russian Olive Gardens: Cool Shade off and on Riverbanks

Summary: Americanized Russian olive gardens make riverbanks cool, shaded oases even though they sometimes menace less assertive life cycles of native vegetation.

Russian olive's flowers and foliage; Arches National Park, east central Utah; Tuesday, May 8, 2012, 13:39:09, photo by NPS (National Park Service)/Neal Herbert: Arches National Park (Arches NPS), Public Domain, via Flicker

Non-native autumn olive shrubs and Russian olive trees advance less controversially through Canada, Mexico and the United States when Americanized Russian olive gardens avoid American poplar and wolf willow native riverbank stands.

Russian olive bandies a century-old reputation as a large ornamental shrub or small tree introduced into North America from its native southern Europe and western Asia. Its introduction can be considered problematic since Russian olive, also called oleaster and trebizond date, counts upon 30- to 50-year life cycles and two reproduction means. Reproduction by germinated seed and resprouted crowns and tolerance of shaded niches drive Russian olive into officially unwelcome weed status in Colorado, Connecticut and New Mexico.

Provincial legislation in Canada and state legislation in the United States respectively exclude autumn olive from Alberta and from Connecticut, Massachusetts, New Hampshire and West Virginia.

The seedling stage of the ornamental woody in the Elaeagnaceae family of oleaster shrubs and trees favors hairless, oval embryonic leaves, called cotyledons, with two-lobed bases.

Richard Dickinson, in Weeds of North America, University of Chicago Press publication from 2014, gives the first leaf stage hairy stems, mealy surfaces and opposite arrangements. Alternate-positioned, mature foliage atop 0.24- to 0.51-inch- (6- to 13-millimeter-) long stalks has dull gray-green to silver colors, elliptical, lance-like or oblong shapes and smooth margins. It is 0.79 to 3.94 inches (2 to 10 centimeters) long, 0.39 to 1.58 inches (1 to 4 centimeters) wide, with brown-dotted undersides and scaly upper-sides.

Similar-looking wolf willow, nicknamed silverberry, juggles 0.79- to 3.15-inch- (2- to 8-centimeter-) long, 0.19- to 1.58-inch- (0.5- to 4-centimeter-) wide leaves outside Americanized Russian olive gardens.

Russian olive, named Elaeagnus angustifolia (narrow-leafed olive chaste-tree), keeps bell-shaped, May- and June-blooming, yellow flowers as solitary blooms or two- to three-flowered inflorescences, called axillary racemes.

The fragrant, regular, 0.12- to 0.47-inch- (3- to 12-millimeter-) long flowers line up one pistil, four sepals with silver-gray exteriors and yellow interiors and four stamens. Wolf willow manages similar-looking bell-shaped, fragrant, regular, yellow 0.19- to 1.58-inch- (0.5- to 4-centimeter-) wide flowers and berry-like, 0.32- to 0.39-inch- (8- to 10-millimeter-) long fruits. Russian olive, described by Swedish botanist Carl Linnaeus (May 23, 1707-Jan. 10, 1778), needs dry, non-explosive, 0.39- to 0.79-inch- (1- to 2-centimeter-) long fruits called achenes.

Fleshy sepals called calyxes occur protectively around Russian olive seeded achenes, whose exteriors offer mealy textures, scale-covered surfaces and silvery impressions in Americanized Russian olive gardens.

Russian olive produces seeds three to five years after germination, and maximum fruit loads nine to 11 years later, on spine-tipped branches with red-brown, smooth bark.

Ninety days of temperatures at 41 degrees Fahrenheit (5 degrees Celsius) quickens germination of brown, oblong, 0.24- to 0.51-inch- (6- to 13-millimeter-) long Russian olive seeds. Seeds remain ready for realizing 16.4- to 39.37-foot (5- to 12-meter) heights and 3.94- to 19.69-inch  (10- to 50-centimeter) diameters by retaining a three-year in-soil viability. Germination starts the woody ornamental down a life cycle of temperatures between minus 49 and plus 114.8 degrees Fahrenheit (minus 45 and plus 46 degrees Celsius).

Riverbanks treat rivers and travelers to cool, shaded oases as long as Americanized Russian olive gardens never take up camp around, over or under native vegetation.

silver-leaved Russian olive trees as non-native newcomers in a ciénega (uniquely Southwestern U.S. wetland system) in a desert; Leonora Curtin Wetland Preserve, La Ciénega, Santa Fe County, north central New Mexico: Una Smith, CC BY SA 3.0 Unported, via Wikimedia Commons

Acknowledgment

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

Image credits:

Russian olive's flowers and foliage; Arches National Park, east central Utah; Tuesday, May 8, 2012, 13:39:09, photo by NPS (National Park Service)/Neal Herbert: Arches National Park (Arches NPS), Public Domain, via Flicker @ https://www.flickr.com/photos/archesnps/7164603622/

silver-leaved Russian olive trees as non-native newcomers in a ciénega (uniquely Southwestern U.S. wetland system) in a desert; Leonora Curtin Wetland Preserve, La Ciénega, Santa Fe County, north central New Mexico: Una Smith, CC BY SA 3.0 Unported, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Cienega2.jpg

For further information:

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

"Elaeagnus angustifolia L." Tropicos® > Name Search.
Available @ http://www.tropicos.org/Name/11600001

Linnaeus, Carl. 1753. "1. Elaeagnus angustifolia." Species Plantarum, vol. I: 121. Holmiae [Stockholm, Sweden]: Laurentii Salvii [Laurentius Salvius].
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/358140

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.