Giant Knotweed (Reynoutria), fam. Polygonaceae.
   Flowers not until the middle of September. It is rarely possible to observe abundantly flowering plants in Kyiv, so their photos are from other places.
   Young leaves and shoots are edible. This plant is a champion in ability to take the heavy metal salts out of the soil where it grows, and to transform them into low-toxic compounds. In favorable conditions the plant greatly expands. For example, in Japan this property is used for land recultivation, after contamination with household and industrial waste; it is planted in the closed landfill sites. It would be great to apply this experience in Ukraine – we have a lot of landfills but not so many viable plant species for them.

---