1. Oak is toxic, to a certain level, yes. Bull mesquite, no. Go nuts.

2. Got local quarries? Streams? Plenty of those 1/2 to 1 ton boulders will decorate nicely. Otherwise, river rocks.

3. Pea gravel is great. 1/4" and 1/8" river rocks are perfect.

Leo

* Knowledge and experience yield wisdom. Sharing wisdom expand the generations with crucial knowledge. Unshared wisdom is worth nothing more than rotting manure.