Two Weeks After 2016 June Solstice Earth Reaches 2016 Aphelion

Summary: On Monday, July 4, 2016, two weeks after the 2016 June solstice, Earth reaches 2016 aphelion, Earth’s farthest orbital point from the sun.

Earth’s remoteness (aphelion) and proximity (perihelion) in orbiting the sun: NASA, Public Domain, via NASA Space Place

At 16:24 Coordinated Universal Time (12:24 p.m. Eastern Daylight Time), Monday, July 4, 2016, two weeks after the 2016 June solstice, Earth reaches 2016 aphelion, the farthest center-to-center orbital point from the sun.

The 2016 June solstice happened Monday, June 20, 2016, at 22:34 UTC (6:34 p.m. EDT). The June solstice marks Earth’s axial tilt, at the North Pole, toward the sun and astronomically opens northern summer and southern winter.

Distances between Earth and sun are expressed in astronomical units (AU). In 2012, the International Astronomical Union (IAU) placed the value of 1 AU at 149,597,870,700 meters, equivalent to 149,597,870.70 kilometers or, roughly, 92,955,807 miles.

Retired NASA astrophysicist Fred Espenak places 2016’s aphelion (Ancient Greek ἀπό, apó, “from” + ἥλιος, hḗlios, “sun”) at 1.0167509 astronomical units (152,103, 781 kilometers) from the sun. Time And Date website’s conversion of AU to miles places the point of aphelion in 2016 at 94,512,904 miles.

Espenak gives a mean aphelic distance of 1.0167103 AU (152,097,701 kilometers) for yearly variations in Earth’s farthest center-to-center distances from the sun. July 2016’s aphelion exceeds the mean aphelic figure by 6,080 kilometers.

July 2016’s aphelion bests the previous year’s remoteness by 10,294 kilometers. On Monday, July 6, 2015, at 19:40 UTC (3:40 p.m. EDT), aphelion measured 1.0166821 AU (152,093,487 kilometers). July 2015’s aphelion was 4,214 kilometers less than the mean aphelic distance of 1.0167103 AU (152,097,701 kilometers).

July 2016’s aphelion bests next year’s remoteness by 11,270 kilometers. On Monday, July 3, 2017, at 20:11 UTC (4:11 p.m. EDT), aphelion will measure 1.0166756 AU (152,092,511 kilometers). July 2017’s aphelion will be 5,190 kilometers less than the mean aphelic distance of 1.0167103AU  (152,097,701 kilometers).

The first and last aphelions of the 21st century are closer to the sun than July 2016’s point of aphelion. Both the century’s opener and its closer are also closer to the sun than the mean aphelic distance.

On Wednesday, July 4, 2001, at 13:37 UTC (9:37 a.m. EDT), Earth’s orbit reached aphelion at 1.0166426 AU (152,087,579 kilometers). The 2001 point is 10,122 kilometers less than the mean aphelic distance of 1.0167103 AU (152,097,701 kilometers). Earth’s aphelion in 2016 is 16,202 kilometers farther from the sun than 2001’s aphelion.

Fred Espenak notes the extremes of minimum and maximum perihelions for the 21st century. The interval between the two extremes is 66 years. The range between the century’s minimum and maximum perihelions is 0.0001419 AU (21,225 kilometers).

On Thursday, July 4, 2019, at 22:11 UTC (6:11 p.m. EDT), Earth’s orbit reaches the 21st century’s maximum aphelion. The distance of 1.0167543 AU (152,104,291 kilometers) exceeds the mean aphelic distance of 1.0167103 AU (152,097,701 kilometers) by 6,590 kilometers.

On Wednesday, July 4, 2085, at 21:34 UTC (5:34 p.m. EDT), Earth’s orbit reaches the 21st century’s minimum aphelion. The distance of 1.0166125 AU (152,083,067 kilometers) is 14,634 kilometers less than the mean aphelic distance of 1.0167103 AU (152,097,701 kilometers).

On Tuesday, July 6, 2100, at 15:58 UTC (11:58 a.m. EDT), Earth’s orbit reaches aphelion at 1.0167027 AU (kilometers). The 2100 point is 1,130 kilometers less than the mean aphelic distance of 1.0167103 AU (152,097,701 kilometers). Earth’s aphelion in 2016 is 7,210 kilometers farther from the sun than 2100’s aphelion.

Earth’s orbit around the sun experiences the extremes of closest point (perihelion) and farthest point (aphelion) because of eccentricities, or deviations. Eccentricities, caused by influences such as the moon, account for an orbit that is somewhat elliptical.

A perfectly circular orbit has an eccentricity of zero. Values higher than zero indicate elliptical orbits. The current mean eccentricity of Earth’s orbit is 0.0167.

The takeaway for Earth’s reach of 2016 aphelion two weeks after the 2016 June solstice is that Earth’s eccentrically elliptical orbit drives a yearly maximum point of remoteness that occurs between July 3 and July 7 in the 21st century.

Seasonal variations; solstices signal maximum polar tipping away from or toward the sun: NASA, Public Domain, via NASA Solar System Exploration

Acknowledgment

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

Image credits:

Earth’s remoteness (aphelion) and proximity (perihelion) in orbiting the sun: NASA, Public Domain, via NASA Space Place @ http://spaceplace.nasa.gov/seasons/en/

Seasonal variations; solstices signal maximum polar tipping away from or toward the sun: NASA, Public Domain, via NASA Solar System Exploration @ http://solarsystem.nasa.gov/galleries.seasonal-variations

For further information:

Byrd, Deborah. “Earth Farthest From Sun on July 4.” EarthSky > Tonight. July 4, 2016.
Available @ http://earthsky.org/tonight/earth-farthest-from-sun-for-year-in-early-july

Byrd, Deborah. “Things to Notice at the June Solstice.” EarthSky > Tonight. June 20, 2016.
Available @ http://earthsky.org/tonight/solstice-brings-northernmost-sunset

Dickinson, David. “Earth at Aphelion 2016.” Universe Today. July 4, 2016.
Available @ http://www.universetoday.com/129513/earth-at-aphelion/#

Erickson, Kristen. “What Causes the Seasons?” EarthSky > Astronomy Essentials > Science Wire > Space. May 3, 2016.
Available @ http://spaceplace.nasa.gov/seasons/en/

Espenak, Fred. “Earth at Perihelion and Aphelion: 2001 to 2100 Greenwich Mean Time.” Astro Pixels > Ephemeris.
Available @ http://www.astropixels.com/ephemeris/perap2001.html

Espenak, Fred. “Solstices and Equinoxes: 2001 to 2100 Greenwich Mean Time.” Astro Pixels > Ephemeris.
Available @ http://www.astropixels.com/ephemeris/soleq2001.html

King, Bob. “Solstice Brings Late Nights, Bright Sights.” Sky & Telescope > Observing. June 15, 2016.
Available @ http://www.skyandtelescope.com/observing/june-solstice-means-late-nights-bright-lights/

MacRobert, Alan. “This Week’s Sky at a Glance, June 17 - 25.” Sky & Telescope > Observing > Sky at a Glance. Friday, June 17, 2016.
Available @ http://www.skyandtelescope.com/observing/sky-at-a-glance/this-weeks-sky-at-a-glance-june-17-25/

McClure, Bruce. “Earliest Sunrises Before Summer Solstice.” EarthSky > Tonight. June 12, 2016.
Available @ http://earthsky.org/tonight/earliest-sunrises-before-june-solstice-jupiter-venus

McClure, Bruce. “Latest Dusk for Northerly Latitudes.” EarthSky > Tonight. June 24, 2016.
Available @ http://earthsky.org/tonight/latest-dusk-at-40-degrees-n-latitude

McClure, Bruce. “Slowest Sunsets Around Solstices.” EarthSky > Tonight. June 21, 2016.
Available @ http://earthsky.org/tonight/longest-sunsets-around-solstices

McClure, Bruce. “Solstice Eve Moon Still Near Saturn.” EarthSky > Tonight. June 19, 2016.
Available @ http://earthsky.org/tonight/solstice-full-moon-on-june-20

“Perihelion, Aphelion and the Solstices.” Time And Date > Sun & Moon.
Available @ http://www.timeanddate.com/astronomy/perihelion-aphelion-solstice.html

“Seasons: Meteorological and Astronomical.” Time And Date > Calendar.
Available @ http://www.timeanddate.com/calendar/aboutseasons.html

Swamp Smartweed (Persicaria hydropiperoides) Has Pinkish White Flowers

Summary: Swamp smartweed (Persicaria hydropiperoides), a widespread New World native perennial, has pinkish white flowers and long, narrow green leaves.

Closeup of swamp smartweed (Persicaria hydropiperoides; syn. Polygonum hydropiperoides) flowers: Robert H. Mohlenbrock/USDA NRCS Wetland Science Institute (WSI), Public Domain, via USDA NRCS (Natural Resources Conservation Service) PLANTS Database

Swamp smartweed (Persicaria hydropiperoides) is a widespread Old World native perennial with pinkish white flowers and long, narrow green leaves.

Persicaria hydropiperoides is known commonly as swamp smartweed. Other common names include false water-pepper smartweed, marsh-pepper smartweed, mild smartweed and mild water-pepper.

Swamp smartweed claims New World homelands spanning North America, Central America and South America. In Northern America, swamp smartweed is native to all but three (Colorado, Utah, Wyoming) of the United States’ Lower 48. Swamp smartweed is native to Puerto Rico but does not occur natively in Alaska, Hawaii or the U.S. Virgin Islands.

Native distribution occurs in half (British Columbia, New Brunswick, Nova Scotia, Ontario, Quebec) of Canada’s 10 provinces. Swamp smartweed is not native to any of Canada’s three territories.

Swamp smartweed’s native occurrence in South America includes not only most of the continent but also the Galápagos Islands. The Pacific Ocean archipelago is Ecuador’s only overseas province.

Great variability across swamp smartweed’s extensive New World range accounts for a lengthy list of scientific synonyms. French botanist and explorer André Michaux (March 7, 1746-Oct. 11, 1802) is responsible for the Old World’s first description of swamp smartweed. His choice of Polygonum hydropiperoides reflects the perennial’s display of ensheathed nodes, a characteristic of the Polygonum genus (Ancient Greek: πολύς, polús, “many” + γόνυ, gónu, “joint, knee”), and also its similarity to water pepper (Persicaria hydropiper; syn. Polygonum hydropiper).

A former synonym, Persicaria hydropiperoides, is now swamp smartweed’s accepted scientific name. The change in genus recognizes the resemblance of smartweed species’ leaves to those of peach trees (Latin: persicum, “peach, Persian fruit”). This scientific name traces back to American botanist John Kunkel Small (Jan. 31, 1869-Jan. 20, 1938) in 1903.

Swamp smartweed thrives in moist to wet habitats. Sunlight requirements range from full sun to partial shade. Swamp smartweed is found in shallow water, muddy soils and wet gravelly and/or sandy soils. Preferred habitats include marshes, pond edges, moist prairies, roadside ditches, wet banks and clearings, and wet woods.

Multiple stems arise from a rhizomatous (Ancient Greek: ῥίζα, rhíza, “root”) root system. Light green stems, which may remain erect or sprawl, measure 2 to 3 feet (0.6 to 0.91 meters).

Green to dark green leaves appear alternately along stems. Leaf blades tend to lack the dark crescent or triangular blotches associated with other smartweed species. Unindented leaf margins, which are unlobed and untoothed, are known as entire.

Linear-lanceolate (Latin: lanceolatus, “lance-shaped”) leaves are long and narrow. Leaf length may range from around 2 inches to over 9 inches (5 to 25 centimeters). Leaf width may measure one-fourth of an inch to almost 1.5 inches (0.4 to 3.7 centimeters).

Petioles, the stalks attaching leaf blades to stems, are diminutive. Petiole length ranges from seven one-hundredths of an inch to about three-fourths of an inch (0.2 to 2 centimeters).

Swamp smartweed stems feature the nodal sheaths, known as ocreas (Latin: ocrea, “legging”), that characterize the Polygonaceae family’s type genus of Polygonum. The sheaths wrap around nodes, points of attachment to stems. Brownish-colored ocreas are surfaced with cilia, stiff hairlike structures.

Various growing conditions and light levels account for a potentially long blooming period. Flowers may open as early as June and last into the autumn months of October or November.

Flowers comprise tepals, or undifferentiated sepals and petals, which form a cup with their fused bases. The diameter of the tiny five-parted flower is about one-eighth of an inch (3 millimeters).

Tiny pinkish, greenish whitish or whitish flowers are loosely displayed in spike-like racemes (Latin: racemus, “cluster of grapes”) that extend usually terminally, at stem tops. Occasionally axillary racemes emerge from upper axils, junctions of leaves and stems.

Swamp smartweed’s fruit is a dry, single-seeded capsule known as an achene (Ancient Greek: ἀ-, a-, “not” + χαίνω, khaínō, “to gape”). The shiny, smooth, three-sided capsule is colored brown, brownish black or black.

Persicaria hydropiperoides plants attest to the appealing variability of smartweed wildflowers. Swamp smartweed’s occurrence in moist or wet habitats guarantees a pleasing blend of tiny pinkish white flowers with long, slender green leaves.

Swamp smartweed (Persicaria hydropiperoides; syn. Polygonum hydropiperoides), Humboldt Bay National Wildlife Refuge, California North Coast: Gordon Leppig and Andrea J. Pickart/US Fish and Wildlife Service, Public Domain, 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:

Closeup of swamp smartweed (Persicaria hydropiperoides; syn. Polygonum hydropiperoides) flowers: Robert H. Mohlenbrock/USDA NRCS Wetland Science Institute (WSI), Public Domain, via USDA NRCS (Natural Resources Conservation Service) PLANTS Database @ http://plants.usda.gov/java/largeImage?imageID=pohy2_002_ahp.tif

Swamp smartweed (Persicaria hydropiperoides; syn. Polygonum hydropiperoides), Humboldt Bay National Wildlife Refuge, California North Coast: Gordon Leppig and Andrea J. Pickart/US Fish and Wildlife Service, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Polygonumhydropiperoides.jpg

For further information:

Chayka, Katy. “Persicaria hydropiperoides (Mild Waterpepper).” Minnesota Wildflowers.
Available @ https://www.minnesotawildflowers.info/flower/mild-waterpepper

Maiz-Tome, L. “Persicaria hydropiperoides.” IUCN Red List of Threatened Species.
Available @ http://www.iucnredlist.org/details/64320296/0

Marriner, Derdriu. “Jumpseed (Persicaria virginiana) Has Tiny White Flowers and Big Green Leaves.” Earth and Space News. Saturday, June 25, 2016.
Available @ https://earth-and-space-news.blogspot.com/2016/06/jumpseed-persicaria-virginiana-has-tiny.html

Marriner, Derdriu. “Pennsylvania Smartweed (Persicaria pensylvanica) Has Tiny Pink Flowers.” Earth and Space News. Sunday, June 19, 2016.
Available @ https://earth-and-space-news.blogspot.com/2016/06/pennsylvania-smartweed-persicaria.html

“Mild Waterpepper Persicaria hydropiperoides.” Illinois Wildflowers > Wetland Wildflowers.
Available @ http://www.illinoiswildflowers.info/wetland/plants/mild_wtpepper.htm

Mohlenbrock, Robert H. Northeast Wetland Flora: Field Office Guide to Plant Species. Chester PA: USDA NRCS (Natural Resources Conservation Service) Northeast National Technical Center, 1995.

“Persicaria hydropiperoides (Michaux) Small.” Canadensys VASCAN (Vascular Plants of Canada Database) > Taxon.
Available @ http://data.canadensys.net/vascan/taxon/8145

“Persicaria hydropiperoides (Michaux) Small.” eFloras > Flora of North America > Flora Taxon.
Available @ http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250037826

“Persicaria hydropiperoides (Michx.) Small.” Digital Atlas of the Virginia Flora.
Available @ http://vaplantatlas.org/index.php?do=plant&plant=3226&search=Search

“Persicaria hydropiperoides (Michx.) Small False Water-Pepper Smartweed.” New England Wildflower Society Go Botany > Simple Key.
Available @ https://gobotany.newenglandwild.org/species/persicaria/hydropiperoides/

“Persicaria hydropiperoides Swamp Smartweed.” Encyclopedia of Life.
Available @ http://eol.org/pages/586678/hierarchy_entries/46190265/details

“Polygonum hydropiperoides Michx. Swamp Smartweed.” USDA NRCS (Natural Resources Conservation Service) PLANTS Database.
Available @ http://plants.usda.gov/core/profile?symbol=POHY2

Tenaglia, Dan. “Polygonum hydropiperoides Michx.” Missouri Plants > White Flowers, Alternate Leaves.
Available @ http://www.missouriplants.com/Whitealt/Polygonum_hydropiperoides_page.html

Jumpseed (Persicaria virginiana) Has Tiny White Flowers and Big Green Leaves

Summary: Jumpseed (Persicaria virginiana), a New World perennial wildflower, has tiny white flowers and big green leaves.

Jumpseed (Persicaria virginiana; syn. Polygonum virginianum), Scotts Run Nature Preserve, Fairfax County, Northern Virginia: Fritz Flohr Reynolds (fritzflohrreynolds), CC BY SA 2.0, via Flickr

Jumpseed (Persicaria virginiana) is a New World native perennial wildflower that has tiny white flowers and big green leaves.

Persicaria virginiana’s New World range stretches mostly across central and eastern North America. In Canada, the perennial wildflower occurs natively only in Ontario and Quebec.

In the United States, Persicaria virginiana claims homelands from Florida northward through the Great Lakes states as well as the New England states of New Hampshire and Vermont. The wildflower’s westernmost reach extends through the Great Plains states from Texas through Nebraska.

Persicaria virginiana is a member of the Polygonaceae, known popularly as the buckwheat, knotweed or smartweed family. Its three scientific synonyms are Antenoron virginianum, Polygonum virginianum and Tovara virginiana. Persicaria virginiana is popularly known as jumpseed, Virginia knotweed or woodland knotweed.

Jumpseed favors moist, well-drained soils. Sunlight requirements range from full sun to partial shade.

Stems arise from underground stems, known as rhizomes (Ancient Greek ῥίζα, rhíza, “root”), that are hard and knotty. Rhizomes usually put forth solitary stems but occasionally several stems emerge.

Stems commonly measure a range of 2 to 3 feet (0.6 to 0.91 meters) in height. The perennial spreads to widths of 3 to 4 feet (0.91 to 1.21 meters).

Stems display the swollen nodes that characterize species of jumpseed’s original genus, Polygonum (Ancient Greek: πολύς, polús, “many” + γόνυ, gónu, “joint, knee”). Small leaflike outgrowths known as stipules (Latin: stipula, “stalk, straw”) wrap around the stem’s nodes, which are points of attachment for jumpseed’s foliage.

The sheath of stipules is known as an ocrea (Latin: ocrea, “legging”). Jumpseed’s ocreas are brownish in color and fringed with hairlike structures known as cilia.

Big, green leaves are arranged alternately along stems. The oval-shaped leaf blade may measure a length of at least 6 inches (15.24 centimeters). Leaf blades may have widths of 3 or 4 inches (7.62 10.16 centimeters).

Rough uppersides of leaves may be hairless or slightly hairy. Undersides are hairy. The leaf blade has smooth, untoothed edges.

Jumpseed’s flowers may open as early as July. Blooming may continue into October.

Flowering typically occurs as terminal racemes (Latin: racemus, “cluster of grapes”) at stem tops. Occasionally jumpseed puts forth axillary racemes, which emerge from the axils, or junctions, of leafstalks and stems. Racemes comprise widely-spaced arrays, in clusters of one to three along the wand-like axis.

Racemes may measure lengths up to 15.74 inches (40 centimeters). Each flower is tiny, with a diameter of about one-eighth of an inch (0.31 centimeters).

Jumpseed’s tiny perianths are four-parted. The perianth (Ancient Greek: περί, perí, “about, around” + ἄνθος, ánthos, “flower”) is the outer part of the flower and comprises sepals, known collectively as calyx, and petals, known collectively as corolla. Jumpseed’s perianth comprises tepals, which are equivalent to both petals and sepals.

Usually jumpseed’s floral coloring is white. Greenish white or pinkish colors sometimes occur.

Jumpseed’s fruit is a dry, egg-shaped, single-seeded capsule known as an achene (Ancient Greek: ἀ-, a-, “not” + χαίνω, khaínō, “to gape”). Remaining intact at maturity, the brown or dark brown achenes depend upon disturbances, such as decay, jostling or predation, to release their seeds. Persicaria virginiana’s common name of jumpseed recognizes jumping of released seeds as a result of contact with achenes.

Variations that emerge during cultivation account for jumpseed’s success as a parent cultivar. Popular jumpseed cultivars include ‘Compton’s Form,’ ‘Lance Corporal,’ ‘Painters Palette’ and ‘Tovara.’

In addition to prettifying cultivated and natural landscapes, Persicaria virginiana appears in Native American ethnobotany as a pulmonary aid. The Cherokee of the southeastern United States combine jumpseed’s leaves with bark from honey locust trees (Gleditsia triacanthos) in a hot infusion to treat whooping cough.

Jumpseed’s profile of long, loose racemes of tiny white flowers and big green leaves shows well in planned and unplanned landscapes. A patch of jumpseed easily creates an interesting niche in native plant gardens. Popular cultivars are attractive as borders and in container gardening.

closeup of jumpseed (Persicaria virginiana; syn. Polygonum virginianum) flowers, Chesapeake and Ohio Canal National Historical Park, Montgomery County, central Maryland: Fritz Flohr Reynolds (fritzflohrreynolds), CC BY SA 2.0, via Flickr

Acknowledgment

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

Image credits:

Jumpseed (Persicaria virginiana; syn. Polygonum virginianum), Scotts Run Nature Preserve, Fairfax County, Northern Virginia: Fritz Flohr Reynolds (fritzflohrreynolds), CC BY SA 2.0, via Flickr @ https://www.flickr.com/photos/fritzflohrreynolds/7950480110/

closeup of jumpseed (Persicaria virginiana; syn. Polygonum virginianum) flowers, Chesapeake and Ohio Canal National Historical Park, Montgomery County, central Maryland: Fritz Flohr Reynolds (fritzflohrreynolds), CC BY SA 2.0, via Flickr @ https://www.flickr.com/photos/fritzflohrreynolds/9481246249/

For further information:

Gaertner, Joseph. 1791. "Persicaria virginiana." De Fructibus et Seminibus Plantarum, volumen alterum: 180. Tubingae [Tübingen, Germany]: Guilielmi Henrici Schrammii [Wilhelm Heinrich Schramm].
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/37208169

Godfrey, Robert K.; Jean W. Wooten. Aquatic and Wetland Plants of Southeastern United States: Dicotyledons. Athens GA: University of Georgia Press, 1981.

“Jumpseed (Persicaria virginiana).” Minnesota Seasons > Plants.
Available @ http://www.minnesotaseasons.com/Plants/jumpseed.html

“Jumpseed (Virginia Knotweed) Persicaria virginiana (L.) Gaertn.” Connecticut Botanical Society > Connecticut Plants.
Available @ http://www.ct-botanical-society.org/Plants/view/479

Marriner, Derdriu. “Pennsylvania Smartweed (Persicaria pensylvanica) Has Tiny Pink Flowers.” Earth and Space News. Sunday, June 19, 2016.
Available @ https://earth-and-space-news.blogspot.com/2016/06/pennsylvania-smartweed-persicaria.html

“Persicaria virginiana.” Atlas of Florida Plants.
Available @ http://florida.plantatlas.usf.edu/Plant.aspx?id=866

“Persicaria virginiana.” Missouri Botanical Garden > Gardens & Gardening > Your Garden > Plant Finder.
Available @ http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=291626

“Persicaria virginiana.” Seeds of Eaden > Ornamental Plants.
Available @ http://www.seedsofeaden.com/ornamental-plants-k7/persicaria-virginiana-b72.html

"Persicaria virginiana (L.) Gaertn." Tropicos® > Name Search.
Available @ http://www.tropicos.org/Name/50080897

“Persicaria virginiana (Linnaeus).” eFloras > Flora of North America > Flora Taxon.
Available @ http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250060702

“Polygonum virginianum L.” Missouri Plants > White Flowers, Leaves Alternate.”
Available @ http://www.missouriplants.com/Whitealt/Polygonum_virginiam_page.html

“Polygonum virginianum L. jumpseed.” USDA NRCS (Natural Resources Conservation Service) PLANTS Database.
Available @ http://plants.usda.gov/core/profile?symbol=POVI2

Few Fossils for Extinct Pygmy Cassowary Natural History Illustrations

Summary: Extinct pygmy cassowary natural history illustrations respect three rare collections and ever so slightly resemble modern dwarf cassowaries.

head and neck illustrations of extant dwarf cassowary (Casuarius bennetti), species thought to somewhat resemble extinct pygmy cassowary: J. Gould's The Birds of Australia Supplement (1868), Public Domain via Internet Archive

Extinct pygmy cassowary natural history illustrations await a more accurate, amplified analysis with the additional appearance of fossil specimens beyond the acknowledged accumulation on mainland Australia and, northward, on Papua New Guinea.

Extinct pygmy cassowaries bear their common name as the smallest cassowary member of the Casuariidae family of one extant emu species and three extant cassowary species. They carry the scientific name Casuarius lydekkeri from the Papuan words kasu and weri for "horned head," and for Richard Lydekker (July 25, 1849-April 16, 1915). Respective descriptions in 1891 and 1911 by the London-born geologist and the London-born zoologist Lionel Walter Rothschild (Feb. 8, 1868-Aug. 27, 1937) drive the scientific name.

Extinct pygmy cassowary natural history illustrations ensue from expeditiously extracting a tibiotarsus's (shin-shank) distal (farther) end from Pleistocene ("Newest") Age sediments 2,588,000 to 11,700 years ago.

The Ice Age tibiotarsus fits into extinct pygmy cassowary natural history illustrations as the holotype (standard) specimen that furnished the species' official scientific description and name.

The Trustees of the Australian Museum in Sydney, New South Wales, gave the British Museum the cast of a specimen of four geographically disparate suggested provenances. The Mining Museum, Australian Museum and University of California Museum of Paleontology held the original respectively as unnumbered, MF 1268 in the 1940s and in 1954. Alden H. Miller (Feb. 4, 1906-Oct. 9, 1965) of the Berkeley-based museum identified the original, in November 1960, as inspiring British Museum cast number A 158.

A Mining Museum-labeled tray, Lydekker descriptions and Rothschild keys respectively judged MF 1268 (now AMF50094) as from diatomaceous deposits at Cooma, Wellington Valley "cavern-deposits" and Queensland.

Cooma and Wellington Caves never kept diatomaceous deposits or AMF50094-like kinds of bone fossilization while nobody knows of Queensland as other than a lapsus ("[involuntary] error").

Like fossils near Bulolo at Awe and Pureni, Southern Highlands, let Michael Plane, Patricia Vickers Rich and Natalie Schroeder list Papua New Guinea in June 1988. The Bureau of Mineral Resources geologist and the two Monash University earth scientists mentioned phalanges (fingers) from Awe's Pliocene ("[continuation of the modern-like] more recent") sediments. They noted the Pureni-fossilized synsacrum and partial pelvis, left and right femora (thigh) and proximal (nearer) tarsometatarsi (shank-foot), distal and proximal tibiotarsus and left distal tarsometatarsus.

Extinct pygmy cassowary natural history illustrations offer an obscurely flightless bird from one leg bone, three finger bones from Awe and eight skeletal bones from Pureni.

Extinct pygmy cassowary natural history illustrations present the smallest known cassowary with the deepest-ended, deepest-jointed shin-shank bone, the narrowest, shallowest pelvis and the narrowest, trimmest thigh.

Extinct pygmy cassowary natural history illustrations queue up deep-ended, smooth-margined shank-foot bones with deep, muscle-based depressions, distal foramen (lower-end openings) and unobtrusively rising and splaying undersides. The Plane, Rich and Schroeder article resisted "significant differences" between AMF50094 and CPC26605a-h, excluding the former's shin-shank grooves "deeper with respect to width" than the latter's. It suggested Awe fingers as longer than somewhat similarly compressed, deep dwarf pygmy cassowary fingers and smaller than present-day northerners (Casuarius unappendiculatus) and southerners (Casuarius casuarius).

Extinct pygmy cassowary natural history illustrations tend toward dwarf pygmy-like biogeographies and fingers and pelvises on fossils otherwise "clearly distinct from corresponding bones of extant cassowaries."

Cast at the British Museum, described in 1891 by English geologist Richard Lydekker, was made from right distal tibiotarsus fossil of extinct pygmy cassowary (Casuarius lydekkeri) held in Australian Museum (1872 photo), Sydney, New South Wales: State Library of New South Wales, Public Domain, 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:

head and neck illustrations of extant dwarf cassowary (Casuarius bennetti), species thought to resemble extinct pygmy cassowary; English ornithologist and avian artist John Gould (Sept. 14, 1804-Feb. 3, 1881), illustrator; English zoological illustrator Henry Constantine Richter (June 7, 1821-March 16, 1902), lithographer; J. Gould's The Birds of Australia Supplement (1868), Plate 72, opposite page 143: Public Domain via Internet Archive @ https://archive.org/stream/birdsAustraliasSuppGoul#page/72/mode/1up

Cast at the British Museum, described in 1891 by English geologist Richard Lydekker, was made from right distal tibiotarsus fossil of extinct pygmy cassowary (Casuarius lydekkeri) held in Australian Museum in Sydney, New South Wales; 1872 photo by Australian photographer Charles Percy Pickering (1825-September 1908): State Library of New South Wales, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:SLNSW_479514_11_Australian_Museum_SH_564.jpg

For further information:

Dawson, Lyndall. 1 August 1985. "Marsupial Fossils From Wellington Caves, New South Wales: The Historic and Scientific Significance of the Collections in the Australian Museum, Sydney." Records of the Australian Museum, vol. 37, issue 2: 55-69. Sydney, Australia: The Australian Museum. DOI:10.3853/j.0067-1975.37.1985.
Available @ https://australianmuseum.net.au/uploads/journals/17640/335_complete.pdf

Gould, John. 1868. "Casuarius Bennetti, Gould. Bennett's Cassowary." The Birds of Australia. Supplement: pages 143-144, Plates 72-73. London, England: Printed for the Author by Taylor and Francis.
Available via Internet Archive @ https://archive.org/stream/birdsAustraliasSuppGoul#page/72/mode/1up

Lydekker, Richard. 1891. "Casuarius, sp." Catalogue of the Fossil Birds in the British Museum (Natural History), Cromwell Road S.W.: 353-354. London, England: Printed by Taylor and Francis for the British Museum (Natural History).
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/8390136

Mahoney, J.A.; and W.D.L. (William David Lindsay) Ride. 1975. "Index to the Genera and Species of Fossil Mammalia Described From Australia and New Guinea Between 1838 and 1968 (Including Citations of Type Species and Primary Type Specimens)." Western Australian Museum Special Publication No. 6. Perth, Australia: Printed for the Trustees of the Western Australian Museum by the Government Printer.
Available @ http://museum.wa.gov.au/sites/default/files/INDEX%20TO%20THE%20GENERA%20AND%20SPECIES%20OF%20FOSSIL%20MAMMALIA%20DESCRIBED%20FROM%20AUSTRALIA%20AND%20NEW%20GUINEA%20BETWEEN%20FROM%201838%20AND%201968.pdf

Marriner, Derdriu. 3 June 2016. "Southern Cassowary Natural History Illustrations: Australian Big Bird." Earth and Space News. Friday.
Available @ https://earth-and-space-news.blogspot.com/2016/06/southern-cassowary-natural-history.html

Marriner, Derdriu. 10 June 2016. "Dwarf Cassowary Natural History Illustrations: New Guinean Little Bird." Earth and Space News. Friday.
Available @ https://earth-and-space-news.blogspot.com/2016/06/dwarf-cassowary-natural-history.html

Marriner, Derdriu. 17 June 2016. "Northern Cassowary Natural History Illustrations: New Guinean Big Bird." Earth and Space News. Friday.
Available @ https://earth-and-space-news.blogspot.com/2016/06/northern-cassowary-natural-history.html

Miller, Alden H. (Holmes). 19 June 1962. "The History and Significance of the Fossil Casuarius lydekkeri." Records of the Australian Museum, vol. XXV, no. 10: 235-238. Sydney, Australia: The Australian Museum. DOI:10.3853/j.0067-1975.25.1962.662
Available @ https://australianmuseum.net.au/uploads/journals/17417/662_complete.pdf

Rich, P.V. (Patricia Vickers); Michael Plane; and Natalie Schroeder. June 1988. "A Pygmy Cassowary (Casuarius lydekkeri) From Late Pleistocene Bog Deposits at Pureni, Papua New Guinea." Journal of Australian Geology & Geophysics, vol. 10, no. 4: 377-389.
Available @ https://d28rz98at9flks.cloudfront.net/81234/Jou1988_v10_n4_p377.pdf

"The Recently Extinct Plants and Animals Database Extinct Birds: Casuarius lydekkeri." Cubits.org.
Available @ http://cubits.org/theextinctioncubit/db/extinctbirds/view/91089/

Rothschild, Walter, Hon. 1911. "On the Former and Present Distribution of the So-Called Ratite or Ostrich-like Birds With Certain Deductions and a Description of a New Form by C.W. Andrew: 17. C. lydekkeri." Verhandlungen des V. Internationalen Ornithologen-Kongresses in Berlin 30. Mai bis 4. Juni 1910: 162. Berlin, Germany: Deutsche Ornithologische Gesellschaft, 1911.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/32626719

June 2016’s Waning Gibbous Moon Shows Mare Nubium in Lunar Southwest

Summary: June 2016’s waning gibbous moon, from Tuesday, June 21, to Sunday, June 26, shows Mare Nubium in the lunar southwest.

Mare Nubium’s lunar location; image taken by Clementine spacecraft March 15, 1994: NASA, Public Domain, via NASA

June 2016’s waning gibbous moon, waning from Tuesday, June 21, to Sunday, June 26, shows Mare Nubium in the lunar southwest. The lunar southwest lies in the lower quarter of the left half of the moon’s near side.

Mare Nubium is visible to unaided eyes in the Northern Hemisphere during the moon’s full, waning and last quarter phases. During the waning and last quarter phases of the lunar cycle, the left half of the moon is illuminated for moon watchers in the Northern Hemisphere’s temperate and high latitudes.

The moon's full phase is not necessarily the best phase for aided viewing of Mare Numbium and other lunar features. A moon filter is recommended to counter the full moon's extreme brightness. Topographic contrasts are more dramatic in other phases.

After turning full Monday, June 20, at 7:02 a.m. Eastern Daylight Time (11:02 Coordinated Universal Time), June 2016’s moon then begins decreasing its illumination, or waning. As the sixth phase in the eight-phase lunar cycle, the waning gibbous moon features more than 50 percent illumination of the lunar disk, from an Earth-based perspective.

Moonrise times span super late evening to early morning for June 2016’s waning gibbous moon. The waning gibbous moon rises Tuesday, June 21, at 11:33 p.m. EDT (03:33 UTC); Thursday, June 23, at 12:33 a.m. EDT (04:33 UTC); Friday, June 24, at 1:34 a.m. EDT (05:34 UTC); Saturday, June 25, at 2:33 a.m. EDT (06:33 UTC); Sunday, June 26, at 3:32 a.m. EDT (07:32 UTC).

Moonset times span afternoon hours for June 2016’s waning gibbous moon. The waning gibbous moon sets Wednesday, June 22, at 2 p.m. EDT (18:00 UTC); Thursday, June 23, at 2:43 p.m. EDT (18:43 UTC); Friday, June 24, at 3:22 p.m. EDT (19:22 UTC); Saturday, June 25, 3:56 p.m. EDT (19:56 UTC); Sunday, June 26, at 4:28 p.m. EDT (20:28 UTC).

Mare Nubium numbers among the dark areas of the moon that are known singularly as mare and plurally as maria. These dark features derive their name from the Latin word for “sea.”

Lunar maria are actually flat, low-elevation plains. Lunar maria cover approximately 16 percent of the lunar surface. Mare Nubium measures a diameter of 714.5 kilometers (443.96 miles).

Binoculars and telescopes reveal specifics of Mare Nubium’s location on the lunar surface. The dark feature is sited east of the vast Oceanus Procellarum and west of the densely cratered Southern Highlands.

Tycho, a bright, young impact ray crater in the Southern Highlands, lies south of Mare Nubium. Tycho’s diameter measures 86 kilometers (53.43 miles). A prong of Tycho’s rays of impact-ejected materials frames Bullialdus crater in Mare Nubium’s western part.

Pitatus crater is found at Mare Nubium’s southern edge. The ancient impact crater’s northwestern well displays heavy wear. A narrow cleft in the wall joins Pitatus with Hesiodus, a smaller lunar crater. Pitatus has a diameter of 100.63 kilometers (62.54 miles).

Rupes Recta (Latin: “Straight Cliff”) is a linear fault, known as a rille, in the southeastern Mare Nubium. Commonly called the Straight Wall, has a length of 115.95 kilometers (72.04 miles).

Jesuit astronomer Giovanni Battista Riccioli (April 17, 1598-June 25, 1671) developed a systematic approach to lunar nomenclature. He gave the Latin name to the dark, prominent feature in the near side’s southwestern sector. Mare Nubium translates as “Sea of Clouds.”

The Jesuit astronomer selected Bulldialdus as the Latinized form of the crater’s namesake, French cleric astronomer Ismaël Boulliau (Sept. 28, 1605-Nov. 25, 1694). Hesiodus is named after Hesiod, an ancient Greek epic poet whose works usually are placed in the 8th and/or 7th century BCE (Before Common Era). Sixteenth-century Italian astronomer and mathematician Pietro Pitati is Pitatus crater’s namesake. Tycho crater honors Danish astronomer and nobleman Tycho Brahe (Dec. 15, 1546-Oct. 24, 1601).

The takeaway for the showing of dark Mare Nubium by June 2016's waning gibbous moon is the lunar disk's easy, unaided visibility that encourages deeper familiarity via binoculars and telescopes.

Bullialdus, Hesiodus and Pitatus craters in Mare Nubium, published May 1964 by U.S. Air Force Aeronautical Chart and Information Center: U.S. Air Force and NASA, Public Domain, via US Geological Survey Gazetteer of Planetary Nomenclature; Universities Space Research Association (USRA) Lunar and Planetary Institute (LPI)

Acknowledgment

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

Image credits:

Mare Nubium’s lunar location; image taken by Clementine spacecraft March 15, 1994: NASA, Public Domain, via NASA @ http://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lroc_20090702_a.html

Bullialdus, Hesiodus and Pitatus craters in Mare Nubium, published May 1964 by U.S. Air Force Aeronautical Chart and Information Center: U.S. Air Force and NASA, Public Domain
Available via US Geological Survey Gazetteer of Planetary Nomenclature @ http://planetarynames.wr.usgs.gov/Page/Moon1to1MAtlas
Available via Universities Space Research Association (USRA) Lunar and Planetary Institute (LPI) @ http://www.lpi.usra.edu/resources/mapcatalog/LAC/lac94/

For further information:

Consolmagno, Guy; Dan M. Davis. Turn Left at Orion: Hundreds of Night Sky Objects to See in a Home Telescope -- and How to Find them. Fourth edition. New York NY: Cambridge University Press, 2011.

Dutch, Steven. “The Moon: Near Side.” University of Wisconsin Green Bay > Steve Dutch > Geology Coloring Book.
Available @ https://www.uwgb.edu/dutchs/GeolColBk/MoonNear.HTM

Fielder, Gilbert. “On the Origin of Lunar Rays.” Astrophysical Journal, vol. 134 (September 1961): 425. DOI: 10.1086/147169
Available via Harvard ADSABS (NASA Astrophysics Data System Abstracts) @ http://adsabs.harvard.edu/full/1961ApJ...134..425F

Fuller, David. "Moon Maps." Eyes on the Sky > Moon.
Available @ http://www.eyesonthesky.com/Moon.aspx

Harrington, Philip S. Cosmic Challenge: The Ultimate Observing List for Amateurs. New York NY: Cambridge University Press, 2011.

International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN). “Hesiodus.” US Geological Survey Western Region (WR) > Gazetteer of Planetary Nomenclature > Nomenclature > The Moon > Mare, Maria. Last updated Oct. 18, 2010.
Available @ http://planetarynames.wr.usgs.gov/Feature/2485

International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN). “Mare Nubium.” US Geological Survey Western Region (WR) > Gazetteer of Planetary Nomenclature > Nomenclature > The Moon > Mare, Maria. Last updated Oct. 18, 2010.
Available @ http://planetarynames.wr.usgs.gov/Feature/5369

International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN). “Pitatus.” US Geological Survey Western Region (WR) > Gazetteer of Planetary Nomenclature > Nomenclature > The Moon > Mare, Maria. Last updated Oct. 18, 2010.
Available @ http://planetarynames.wr.usgs.gov/Feature/4740

King, Bob. “How to See Lunar Craters With the Naked Eye.” Sky & Telescope > Observing. Oct. 28, 2015.
Available @ http://www.skyandtelescope.com/observing/how-to-see-lunar-craters-with-the-naked-eye102820152810/

“LRO’s First Moon Images.” NASA > Missions > LRO (Lunar Reconnaissance Orbiter) > News & Media Resources. July 2, 2009.
Available @ http://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lroc_20090702_a.html

Marriner, Derdriu. “May 2016’s Waning Gibbous Moon Shows Dark Mare Imbrium.” Earth and Space News. Wednesday, May 25, 2016.
Available @ https://earth-and-space-news.blogspot.com/2016/05/may-2016s-waning-gibbous-moon-shows.html

Marriner, Derdriu. “Waning Gibbous Moon: Sixth Lunar Phase Still Shines Even With Lessening Light.” Earth and Space News. Monday, March 9, 2015.
Available @ https://earth-and-space-news.blogspot.com/2015/03/waning-gibbous-moon-sixth-lunar-phase.html

Moller, Bob. “06/16/2016 -- Ephemeris -- The Moon Tonight.” Bob Moler’s Ephemeris Blog. June 16, 2016.
Available @ https://bobmoler.wordpress.com/2016/06/16/06162016-ephemeris-the-moon-tonight/

“Pitatus and Hesiodus.” Inconstant Moon.
Available @ http://www.inconstantmoon.com/img_pita_mh.htm

“Powerful Pixels: Mapping the ‘Apollo Zone.’” NASA > News & Features > News Topics > Solar System > Features. Dec. 28, 2011.
Available @ http://www.nasa.gov/topics/solarsystem/features/apollo-zone-map.html

Scagell, Robin. Firefly Complete Guide to Stargazing. Buffalo NY: Firefly Books Inc.; Richmond Hill, Canada: Firefly Books Ltd.; London, England: Philip's, 2015.

Webb, Brian. “Coordinated Universal Time (UTC).” Space Archive. March 27, 2016.
Available @ http://www.spacearchive.info/utc.htm

Pennsylvania Smartweed (Persicaria pensylvanica) Has Tiny Pink Flowers

Summary: Pennsylvania Smartweed (Persicaria pensylvanica), an annual New World wildflower, has tiny pink flowers.

Pennsylvania smartweed (Polygonum pensylvanicum), James Woodworth Prairie Preserve, Glenview, Cook County, northeastern Illinois: Frank Mayfield (gmayfield10), CC BY SA 2.0, via Flickr

Pennsylvania smartweed (Persicaria pensylvanica) is a New World annual wildflower that has tiny pink flowers and a lengthy blooming period from May through October.

Persicaria pensylvanica thrives in disturbed, moist, open landscapes. Preferred habitats include marshes, meadows, roadside ditches, streamsides, swamps and wetland margins. The plucky wildflower easily tolerates gravel, mudflats, rocks and sand.

The New World native accepts a range of sunlight requirements. Open habitats offer full sun, but the unfussy wildflower tolerates dappled sunlight and partial shade.

Common names for Persicaria pensylvanica are Pennsylvania smartweed, pink knotweed and pinkweed.

The annual’s fibrous root system centers on a shallow taproot. The straight, tapering, vertical primary root grows downward. Subsidiary rootlets sprout laterally.

Stems range in height from 2 to over 4 feet (0.6 to 1.21 meters). Stem height may even measure 6 feet (1.82 meters).

Lance-shaped leaves form alternate arrangements along stems. Green leaves, which sometimes display brownish purple splotches, contrast well with reddish-tinged stems. Pinkweed’s leaf blade has entire edges, that is, smooth, untoothed margins.

A ribbed sheath, known as an ocrea (Latin: ocrea, “legging”), surrounds nodes, the points of attachment for flowers and leaves. Green sheaths have purplish or reddish brown tinges.

The profuse blooming of tiny pink flowers may occur over a lengthy period, from as early as May to as late as October. Small, five-parted, whitish pink flowers are borne on dense racemes (Latin: racemus, “cluster of grapes”). Clusters occur as axillary (at leaf-stem junction) and terminal (at stem top) growths.

Pink knotweed’s seeds are black and shiny, with a flattened, roundish shape. Seeds are popular food sources for such waterfowl as ducks and geese. Mourning doves (Zenaida macroura), Northern bobwhites (Colinus virginianus) and ring-necked pheasants (Phasianus colchicus) join waterfowl in appreciation of pink knotweed seeds. Small mammals that consume the seeds include fox squirrels (Sciurus niger), muskrats (Ondatra zibethicus) and white-footed mice (Peromyscus leucopus).

The pink-flowered New World native claims homelands in Canada and the United States. Pennsylvania smartweed occurs natively in Canada from the easternmost prairie province of Manitoba eastward through Ontario, Quebec, New Brunswick and Nova Scotia.

For the island of Newfoundland, Pennsylvania smartweed is considered as an introduced species by Canadensys, an online biodiversity database maintained by members of the Canadian Biodiversity Information Facility (CBIF) and the Global Biodiversity Information Facility (GBIF). The U.S. Department of Agriculture’s PLANTS Database considers it as native to the large Atlantic Ocean island.

Pennsylvania smartwood is not found in any of Canada’s three territories. Nor does its native range include three western provinces, from British Columbia westward through Saskatchewan. The annual wildflower is not native to Labrador or Prince Edward Island.

In the United States, Pennsylvania smartweed occurs natively in Alaska and in all but three of the Lower 48 states. Stateside, the long-blooming wildflower is not native to Idaho, Utah or Washington. Nor does it occur natively in Hawaii, Puerto Rico or the U.S. Virgin Islands.

Pennsylvania smartweed is a member of the Polygonaceae, known commonly as buckwheat, knotweed or smartweed family. The name of Polygonaceae acknowledges the swollen nodes, or points where new growth appears along stems, that characterize the family’s type genus, Polygonum (Ancient Greek: πολύς, polús, “many” + γόνυ, gónu, “joint, knee”). A sheath of stipules (Latin: stipula, “stalk, straw”), small leaflike outgrowths at the base where petioles, or leafstalks, emerge along stems gives the nodes a swollen appearance.

Taxonomic pioneer Carl Linnaeus (May 23, 1701-Jan. 10, 1778) named and classified Pennsylvania smartweed’s original genus, Polygonum. In 2005, the Flora of North America (FNA) Ed Committee designated Persicaria pensylvanica as the pink-flowered wildflower’s accepted name and Polygonum pensylvanicum as an accepted synonym. The genus name of Persicaria reflects the similarity of species’ leaves to those of peach trees (Latin: persicum, “peach, Persian fruit”).

The pretty pink pastels of Pennsylvania smartweed’s flowers draw attention in natural landscapes. The pink wildflower’s lengthy blooming period qualifies Pennsylvania smartweed for showy placements in native plant gardens. The profusion of tiny pink flowers, especially as terminal clusters, also shows well in roadside ditches about one mile northeast of my home.

Pennsylvania smartweed (Polygonum pensylvanicum), Huffman Prairie, Dayton, southwestern Ohio: Andrew C (acryptozoo), CC BY 2.0, via Flickr

Acknowledgment

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

Image credits:

Pennsylvania smartweed (Polygonum pensylvanicum), James Woodworth Prairie Preserve, Glenview, Cook County, northeastern Illinois: Frank Mayfield (gmayfield10), CC BY SA 2.0, via Flickr @ https://www.flickr.com/photos/gmayfield10/4538346916/

Pennsylvania smartweed (Polygonum pensylvanicum), Huffman Prairie, Dayton, southwestern Ohio: Andrew C (acryptozoo), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/acryptozoo/21143913879/

For further information:

Abbey, Timothy. “Weed of the Month: Pennsylvania Smartweed.” PennState Extension > Plants and Pests > Green Industry > News > 2015. March 4, 2015.
Available @ http://extension.psu.edu/plants/green-industry/news/2015/pennsylvania-smartweed

“Common Name Arrow-Leaved Tearthumb (Arrowleaf Tearthumb).” Friends of the Wild Flower Garden > Archive > Plants - Common Name List.
Available @ http://www.friendsofthewildflowergarden.org/pages/plants/arrowleaftearthumb.html

Davis, Lee; USDA NRCS Northeast Plant Materials Program. USDA NRCS (Natural Resources Conservation Service) PLANTS Database > Plant Fact Sheet. Last edited June 8, 2009.
Available @ http://plants.usda.gov/factsheet/pdf/fs_pope2.pdf

“Pennsylvania Smartweed Persicaria pensylvanica laevigata.” Illinois Wildflowers > Prairie Wildflowers.
Available @ http://www.illinoiswildflowers.info/prairie/plantx/pa_smartweedx.htm

“Persicaria pensylvanica (L.) G. Maza.” Go Botany > Simple Key > All Other Flowering Non-Woody Plants > All Other Herbaceous Flowering Dicots.
Available @ https://gobotany.newenglandwild.org/species/persicaria/pensylvanica/

“Persicaria pensylvanica (L.) M. Gomez.” Digital Atlas of the Virginia Flora.
Available @ http://vaplantatlas.org/index.php?do=plant&plant=3230

“Persicaria pensylvanica (Linnaeus).” eFloras > Flora of North America > Flora Taxon.
Available @ http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250037745

“Persicaria pensylvanica (Linnaeus) M. Gómez de la Maza.” Canadensys > VASCAN (Vascular Plants of Canada Database).
Available @ http://data.canadensys.net/vascan/taxon/8153?lang=en

Stanford, E.E. “Polygonum pensylvanicum and Related Species.” Rhodora, vol. 27, no. 322 (October 1925): 173-184.
Available via Biodiversity Heritage Library @ http://www.biodiversitylibrary.org/page/587786

Tenaglia, Dan. “Polygonum pensylvanicum L.” Missouri Plants > Pink Flowers, Leaves Alternate.
Available @ http://www.missouriplants.com/Pinkalt/Polygonum_pensylvanicum_page.html