Lemond, the best way to identify Oak species is by examining the leaves. Look up Red Oak, Black Oak, and White Oak, all three have distinctive leaves that are easy to tell apart, and make it easy to identiy acorns. Swamp oaks, chestnut oaks, pin oaks are a few others worth knowing. I suspect the dark ones and almost fully encased within the shell? Those would be black oaks, there' s a ton of them falling outside my window. Not high on the preference list of deer, but in a year like this, with few white oaks producing, well, they may be the only game in town, Once the combines roll through, the deer will move into the woods and find them. The other' s are probably chestnut oaks. They are very low on a list of a deer' s preferred foods. They' ll be dark green or brown, very shiny, about 1 1/2" long, and only about 1/4 encased within the shell. It' s a good idea for every bowhunter to learn the various oaks.