Oh, and I probly wouldn't even worry about roots unless they are mad close to perfect.....
Just plan on layering them for a nice spread later.
Which means you can start a bend a foot up later, so you don't have to be working with your face in the dirt, and just layer it right below that later.
Of course, there is the time it takes for roots to bark up, which should be accounted for, hence, work the roots nice yearly on any good ones.
Sorce