I would put down a landscape fabric before putting any kind of stone down, this will keep your material from embedding in your soil. The fabric I use has a 20 year guarantee as long as it's covered with a few inches of material, I think mine requires 3-4" and I'm told it will last much longer than that. It looks like a roll of felt, very very durable, comes in different widths and thickness's. I have a different type of fabric keeping my gravel from disappearing on my driveway, it's more like a woven plastic tarp but wasn't recommended for using around my pond.

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