Um, yeah, filed under “S” for “Sez you”. A lot of the grass in my front yard is rooted in previous generations of grass in addition to all the rocky stuff. Plus squirrel carcasses, etc. N.B. none of this will ever be converted into petroleum by migrating thousands of feet down into the Earth.
If you don’t want fungi or bacteria in your car, you should never, ever let human beings into it. We’re covered in that stuff.
“Has compost or other large quantities of dead stuff been stored in the trunk of this vehicle”?
“Why, yes, I HAVE been to the grocery store!”