For me I look for ferns ,christmas,maidenhair, rattle snake or yer standard poly pods,they indicate the correct moisture levels and light needed. A steep hill that is wind blown does not sound ideal,and then add the oak trees and those conditions will probably be to dry. If there is no ferns look else where.
As for the spring or fall, personally the fall is better for seed needing one more winter to sprout, because they will sprout in the frozen ground so your really ahead. They also will have had the winter to settle in, spring planting is possible but you have to keep the seed cool for another winter and then some start sprouting.
If you are talking about planting green seed in the spring and waiting till the next spring for them to sprout you may lose some to the turkeys or rodent like critters.I have best luck planting sratified in the late fall just before the snow.
Guy