Spotted spurge
Euphorbia maculata, known as spotted spurge, prostrate spurge, milk purslane, or spotted sandmat, is a fast-growing annual plant in the family Euphorbiaceae. It is native to North America, where it is generally considered a common weed. It can be found in disturbed soils such as garden beds, along railroad tracks, and in the cracks of sidewalks. It has become a common introduced species throughout the world, including Europe, Japan, Korea, Australia, and New Zealand.
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