They are just the little burs, i dont think they'd hurt the dogs any, but you may want to keep your shoes on.
There are sand spurs. My grandkids called them, prickers.
In light of hurricane Florence, I would highly recommend calling the campground directly before you go to confirm status of the facilities.
There are tiny cactus around the outside edges of the campsites. Boots might not be a bad idea. Or you could just tie them so the can't reach the edges of the site.
Boots would be good. The briars are pretty bad.
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