This pack contains 35 .3ds files, being 5 variations on a tree like shrub, with 7 growth stages for each variation. This is since forrests are not usualy composed of bushes that are all the same size, rather there are bushes at all stages of growth.

These models will probably require a bit of work to get in game as they are quite polygon heavy (100+ polys for a tiny little nub, over 9000 polys for a full shrub) and texture light.  To look and perform their best you will probably want to optomise them for your engine and use some new textures for them.

edit, I've been playing around and I made a lower poly version of one of these plants as a proof of concept, keeping almost all the detail while reducing the full model to 4k polys, which is still large, but less than half the size without a significant reduction in quality, infact i cleaned up a lot of the sharp edges along the way, so its probably better, i've attached the 3ds and a screenshot.