Photoshop :: Sci-fi Morphing Effect?

I want to create a photomanipulation where my dog is standing in the forest, looking to the side, as he's starting to morph into the ground, as if he is becoming part of the forest. Basically, I want it to seem as if the bottom half of his legs are becoming of the earth and dirt, and his tail is morphing into a flower. I have yet to have my dog cooperate and let me take the picture, but the picture will end up looking a little bit like this:

I know how to get the tail to morph into a flower, but I'm kind of unclear how I want the legs to begin morphing into the grass. I still want them to maintain their shape, but seem as if the fur on his legs is becoming green grass instead.

Also, I really want to make this a little more sci-fi, so I was hoping to include visible and swirling earth energy,