Nodding spurge

Euphorbia nutans

"Euphorbia nutans" is a species of "Euphorbia" known by the common names eyebane and nodding spurge. It is native to much of the United States, Eastern Canada, Mexico, Central America, the Caribbean, and Venezuela.
Euphorbia nutans This is a picture of Euphorbia nutans on the South Tract of the Patuxent Research Refuge near Laurel, Maryland. Euphorbia nutans,Geotagged,Nodding spurge,Summer,United States

Appearance

"Euphorbia nutans" is an annual herb growing erect with pairs of oblong leaves along its stems. The leaf may be up to 3.5 centimetres long, hairy or hairless, and finely toothed.

The inflorescence may be solitary or borne in clusters. Each inflorescence is a cyathium, with flat white or red appendages surrounding the actual flowers. At the center of the array of appendages are several staminate flowers surrounding one pistillate flower. The latter develops into a fruit, which is a capsule about 2 millimetres wide.
Nodding Spurge (Euphorbia nutans) On a meadowy roadside near the edge of a dense mixed forest. Very hard to photograph those tiny flowers!!!
https://www.jungledragon.com/image/84571/nodding_spurge_euphorbia_nutans.html Euphorbia nutans,Geotagged,Summer,United States

Distribution

It is reportedly naturalized in parts of Europe as well as in the Middle East, Japan, and New Zealand. It has also been introduced to California. It can be a noxious weed in areas where it has been introduced. As a weed it generally occurs on disturbed ground, or in ornamental flower beds.

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Taxonomy
KingdomPlantae
DivisionAngiosperms
ClassEudicots
OrderMalpighiales
FamilyEuphorbiaceae
GenusEuphorbia
SpeciesE. nutans