Something like a crabapple, or smaller ornamental tree. The line comes through the foundation wall, front of the house(street side) about 18" off the floor. I have at least 5 1/2 feet of earth over it. Is that enough for a smaller tree?What kind of tree? Does the sewer line come through the basement floor of your home or somewhere up the wall on the street sideof the house? If through the floor you probably have at least 9-10 feet of earth over that sewer line. More than enough for smaller ornamental trees.