On an evening walk not too long ago, my five-year-old daughter asked me what was below our feet. As I was busy untangling a dog leash from around my ankles, and trying not to drop the three poop bags in my hands, I inattentively asked her what she meant.
“Like, below our feet,” she repeated.
“Do you mean the ground?”
“Yes. What’s under the ground?”
“Root sy…