Answer: It can sometimes be difficult to find a space for landscape trees and shrubs when existing trees and shrubs have spread out their roots. While you can sever some roots when digging, I think it's best to plant the smallest shrubs and trees you can find so you won't have to disturb the roots of existing trees and shrubs. This way you can dig a smaller hole and as the new tree or shrub grows, it will find root space. The alternative is to find another, less occupied plot of ground for your new landscape plants.
Best wishes with your landscape!
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