Good luck in Sept. The berries will be toward the very end, up high you will find more than down low in terms of berries. That being said choke cherries are usually near water, you find them on the edges of old logging roads. There is some good walking behind the lake. There is a boyscout camp, the road that runs behind there I have seen several bears on in the past couple year. Besides berries, the key is early morning and late evening, like the last half hour of each. Here is a pic of choke cherries.
PS. Your name is the same as the gamewarden in the area. (Kram)