What is Himalayan balsam bashing?

Removal of invasive non-native plants is what a Himalayan balsam bashing is about. The plant in question (Impatiens glandulifera) -- which favors taking over damp grounds and river banks from native plants -- was introduced into British Isles during the reign of Queen Victoria (May 24, 1819 - January 22, 1901) from June 20, 1837 until her death.