What to put under a trampoline?

[glitch]

Underneath our trampoline and climbing frame I have a combination of dandelions and soil. The grass has now completely died off and I don't think I have much hope of re-growing any under it. The garden isn't big enough to move said eyesores so I wondering what I can put down instead.

I'm thinking bark or gravel but I don't want to end up shooting bits of it across the garden if the lawnmower hits the edge of it. I also have a dog and cat so it is a possible new toilet area for them when they spy it depending on what it is.

I'd appreciate any ideas.

We have large bark chippings under ours but it stands over an old pond/rockery we filled in so the little rock wall stops the bark escaping (much) onto the lawn. No doubt the cats and chickens do use it as a toilet and god knows what else, the chickens like scratching around in there anyway and the cats sit under the trampoline, but I don't worry about it as it's under the trampoline and you can't see it!