Question: Will English ivy hurt the walls of my house or my shade trees when it grows up their trunks?
Answer: Vines, English ivy included, do not harm bricks or mortar. They may, however, trap dirt and debris against the brick. That can, in turn, stain the hard surfaces, especially with light-colored brick. As far as your trees are concerned, English ivy will only harm them if it (a) makes a canopy over their leaves, thereby causing excessive shade, or (b) adds too much surface area that can become laden with the weight of ice during winter. For both reasons, it's usually best to confine it to only the trunk.