Ok I have had the same problem on the PC with a geforce graphics card. I don't know what problem this is associated with but it will happen other than fall on older sim 3 packs. The problem lies somewhere in the driver and the graphics processor and the game not communicating properly. Crin is right there is no soulution except change graphic cards. Many of the GE Force cards do not have the shadow 2.0 or above on the driver. So they are not supported for Sims. EA will tell you they are supported but for some reason the GE Force card does this once in awhile for various reasons. I went to an ATI card just because of this issue. Nvidia nor EA will solve the problem on the GE Force cards. I reported the issue on earlier modles to Nvidia and EA they would not fix the issue. You can somethimes get it working again by rebooting the system. For some reason Rebooting clears whatever is causing the problem. Also back up you game and try to start a new game then install your back up agian works sometimes.
Sorry your having this problem it is not the foliage causing the problem it happens when you build a house on your own. Which is what it looks like you did or you dropped a house you built on a lot.
