Can't bake lightmap with trees on a terrain

Hi! Just arrived from Unity 4.6 to 5, and have a problem. My trees don’t want to make shadows when I’m trying to bake it. All tree’s prefabs is static. When I create one tree by prefab - it works. But don’t work with terrain’s trees.

P.S. Sorry for my English.

Tested, worked fine (least in 5.2)