As you may or may not know, the city is widening the street I live on. This means I've lost all my trees and shrubs across the frontage. These plants were my sound barrier between the noisy 55+mph traffic and my house. They're putting up a retaining wall where they have cut off my elevated yard. So I've been trying to figure out what I could plant across the front to dampen the traffic sounds and what wouldn't damage the new wall. One thing that came up in my research is the Rosella Hibiscus. Seems it's an edible, fast growing shrub. I'm thinking I'll plant them close together with an occasional tree in between for more height. Now I need to figure out a tree whose roots won't damage the wall.