Newbie question. My parents' house's backyard has 2 very large trees
with thick roots that stick above ground 2-3 inches , and radiate
from the base of the tree about 20-30 feet. All the grass underneath
the trees are gone because of the canopy and years of dead leaves.
Took 26 55 gallon garbage bags to dispose of the leaves and small
branches Left behind lots of mulch, though.

Do I get lots of topsoil and cover up the roots? How deep under the
topsoil should the roots be? This is flat ground. For one tree, it is
at the base of a hill.

Also, can anyone recommend grass seed which grows with very little
sunlight?

THanks