OH!! So it is supposed to look like a forest floor, or something blobbish. I was starting to feel badly about my smartie comment.
That's a very nice bonsai! How old is it? Or is it someone else's? We have a bonsai club here, tho' every show, their little trees and stumps all look alike. (oops!)
I have one poor tree in a scabby little pot that I call my bonsai. It's a fiddlewood, a local tree that occasionally has fragrant racimes of tiny white flowers. And when it's time to change leaves, the old ones turn bright orange. I mostly ignore it, no fancy pruning except for some new leaf pinching occasionally. It's almost died a couple of times from being too dry, but the dead parts are part of the aged bonsai effect, I say. Bad me!
I'll have to dig it out and take a photo----