Growing grass in a wooded lot is possible, but has its challenges. Grass likes sunshine, and there is little of that in wooded lots, where the tree canopy can capture all the sunshine and deflect the rainfall with the leaves and branches on the trees. Even gardening experts agree that it is difficult to grow grass under the shade of trees. You can have some luck if you use the right kind of grass seed.
Prepare the soil by raking all the forest debris, and breaking up the soil by tilling it with a power tiller or breaking it up with a shovel and spade.
Add soil amendment if your soil is poor. If it is a rich, loamy soil, chances are you won't need to amend it. If the grass you are trying to grow is in a grove of pine trees, you will have to add soil amendments to fight the acidity in the soil that pine needles create. Potash is a good way to counteract the acid soils found in pine forests. You can save fireplace or wood stove ashes for a good source of potash. You will have to apply the potash regularly.
Mix the fescue grass seeds with the Kentucky blue or rye. Your choice of grass seeds depends on your climate. In the hot, arid west, rye grows much better than Kentucky blue grass. Mix the fescue in a two-to-one ratio with the rye or blue grass seed.
Lightly cover with mulch, and water well. You will have to water the seeds several times a day for the first two or three days, and then at least once a day until the grass seeds emerge, which could take 10 days to two weeks.
Make sure as the grass grows that it gets supplemental watering if there are no hard rains. The trees and branches will soak up the water from a light shower, and freshly planted grass needs quite a lot of water to become established.