From Self Sufficientish.com, the urban guide to almost self sufficiency (Urban Homesteading):

Paul Kingsnorth likens this plant to a major supermarket in his book real England. The following paragraph beautifully sums up how both knotweed and Tescos behavior.

“Just as Knotweed is all cloned from one single plant, so the big chains are all cloned from global corporations. Just as Knotweed makes it impossible for the local plant life at its roots, and thus kills off the local insects and the local birds, so the big chain shops kill off the local independent shops around them and thus destroys the local economy. Just as Knotweed will come back again several growing seasons in a row until those of us out there with mallets and rollers are exhausted, so a big supermarket, refused planning permission, will apply again and again until the Council and local people are worn down and give in.”