Trees grow when the character and camera get close to them

Hello I made a terrain in unity pro 3.1 and I used the terrain tools and painted trees on top of the terrain. so far everything works and seems fine. hwoever when I press play and start moving the character (3rd person character with the 3rd person camera attached) the trees start acting weird. teh problem is when the character and the camera get close to the tree the threes closer to camera they suddnely have some sort of growing animation which is really obvious and of course doesn't look good. i thought at first the problem is because of bending attribute but even after turning that down to 0 still this problem occurs. any thoughts about why this happens and what can I do to fix this? regards

It must be the transition between billboard and mesh mode. Try increasing billboard distance (in Terrain Settings) and see if that helps. If it still doesn't work, then I would like to see a video of it.