I have a couple of larger rock beds in my front yard that are composed of plain ol ? 2? or so diameter oval stones. Unfortunately, there is a massive pine tree in the vicinity that constantly sheds really long pine needles (6?-8?). I have tried different kinds of rakes with no success. I also tried vacuuming them out with a pretty powerful shop vac, but that also did not help. I tried the vac in blower mode, and that looked like it might have promise, if it pushed a bit more air. Although, I have a feeling the rocks are going to really start moving with a blower.