In terms of eradication you could try and approach the developer (may also go down quite well in view of recent economic news) and encourage the production of Apple & Knotweed Pie, Knot Ice Cream, Knot Soup, Knotweed Sherbet, Steamed Knotweed Sesame and my personal favourite Strawberry- Knotweed Cobbler - as recommended by some women called D.Smith. An answer to that UK wide problem. Next............