How cleared cotton-mill sites, back yards and ginnels can harbour knotweed, and what to look for at home.
Bolton was built on cotton, and when the mills closed a great many were demolished, their foundations left in the ground and the sites left to scrub or sold on for building. Ground that has been broken up and left alone is just what knotweed prefers, so it can sit on a cleared plot for years before it turns up in a neighbouring yard.
Look at yard corners, the foot of back walls and the ginnel behind your house. Red-purple shoots in spring and tall leafy canes in summer are the giveaway, with brittle brown stems standing through winter.
Leave it alone, photograph it and send us the picture. If it is knotweed, a survey will show how far the roots reach and whether they have crossed a boundary.