can I claim a small piece of land that I have maintained for

There is a piece of land next to my house(property line)I have maintained for 17 years there is a creek after it so it could not be used for anyone else but us. We would like to do something permanent with it, we have already planted trees but we don't want to have to worry about someone giving us a hard time for anything its about 30ft or so at the beginning and then triangles out to the back then a big creek