I've played around with this alittle you might try it. Its kind of a cheap morph effect. It only works with stationary objects. I model an object I.E. a plant. Texture it. I model another plant. Texture it. In Bryce I play with the texture transparency so the first model completely disapears and the second one appears in the next frame...If you use 3 or 4 objects in this fashion It appears that your object is moving/swaying in the wind....Its very crude and a pain in the butt but if your careful you can get it to work.