While out looking for a future supply of sloes, we found hazel nut trees that are absolutely full of nuts. I know that they are not ready until they start to fall, about late Oct - Nov, but don't know how well they keep. I imagine they have to be dried a bit to keep well but am not sure. We must pick before the squirrels take them, although they are important for their winter store.
By the way, not many sloes. We found one bush off the beaten track that we must keep a secret or the sloe gin won't happen this year.