This is Science Friday. I'm Ira Flato. Later in the hour, a conversation about rodents and the

complicated paths of science careers and checking in on the sounds of the planet with Science Radio

Pioneer and nature recordist Jim Metzner. But first, we're talking soil. Now, I know you might

feel the earth move under your feet, but I bet you didn't know

that there's soil high above your head way up in the treetops where ferns and mosters and flowers

grow on top of the forest. Yes, they do. A new study in the journal Geoderma picks apart the factors

that drive how canopy soil is made. Joining me is the

lead author Jessica Murray, ecologist and PhD candidate at Utah State University in Logan, Utah. Welcome to

Science Friday. Thank you, Ira. I'm so happy to be here. That's nice to have you. You know, I'll bet you

that hardly anybody has ever heard of canopy soil.

Tell us what that is.

How does it get up on the top of the trees there?

Yeah, well, I hadn't heard of it either until I saw it pretty much.

Yeah, so canopy soil is called that because it is found in tree canopies on tree branches

and the cratches of trees. And it develops

over long periods of time. We don't know exactly how long, but probably many decades, if not

hundreds of years, through the decomposition of epiphytes, which is the name for plants that

grow on other plants. You might have mosses, you might have vascular epiphytes, which is the name for plants that grow on other plants. You might have mosses,

you might have vascular epiphytes, so shrubs, trees, et cetera. The leaves produced by what we call

the host tree, the roots of the epiphytes, any mosses, all of this organic material decomposing

over time on tree branches builds up this sometimes really thick layer of soil.

Wow. Wow. And your study looked at how the canopy soil is made, right? So tell us what factors did you zoom in on?

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