I fly out of an airport that used to have a lot of trees along one side of the runway. It had both of the effects you mention, of moderating the wind but also c

I fly out of an airport that used to have a lot of trees along one side of the runway. It had both of the effects you mention, of moderating the wind but also causing turbulence. The problem isn’t just the ends, but also the top, as the wind curls over. Overall I think the benefit is fairly small, and you’re a lot better off building perpendicular runways if you can.