When it comes to the trees or walking trail???? This is a matter of personal opinion and the community. With a walking trail behind, if you are in a high crime area, that could be viewed as a negative, in a golf course community, it could be a huge positive.
As for trees, that's definitely more desireable than backing to another home or a road. As for a walking trail, I've heard both from buyers - some love it, some hate it.
Not sure that is a concern in your area. If so, I would consider the resale effects of large trees within "crushing distance." :o)