Potato weed (Galinsoga parviflora), fam. Asteraceae.
   A weed in the city. Originates from America (Peru), where it have got from in eighteenth century to Europe, and during a couple more centuries spread throughout all the Eurasian continent. Most weeds fade naturally after pulling out, when lying on the ground. However, potato weed has amazing stamina, irresisitible desire to put down aerial roots (especially when the plant has been plucked in rainy days). In a short while they get into the soil, and the plant resumes its growth.
   There is little practical benefit from potato weed. Its decoction is used against rheumatism (externally) and other inflammatory diseases.

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