Field workers spread locally-sourced bat guano fertilizer on biodynamically grown marijuana plants at the SPARC cannabis farm in Glen Ellen, Calif. on Friday, July 14, 2017. Erich Pearson's expansive ...

Dear Stoner: I was at my neighborhood “gardening” store recently and noticed an ingredient I was not familiar with: bat guano. What is that? Dear L.L.: The answer is poop. Bat poop, specifically.

Bat poop—yes, bat poop—is far more fascinating than you might think. You probably don’t give it much thought (unless it’s in your attic), but believe it or not, bat droppings have shaped history, ...

Dear L.L.: The answer is poop. Bat poop, specifically. While bats may be disease-carrying flying rats with poor eyesight, their excrement is like the superpoop of the animal-poop world. Not only can ...