From the brains behind brains on, this is the moment of um.

Answering those questions that make you go.

Uh, uh, uh, uh, uh, um.

Um, um, um, um, um. The moment of um comes to you from 8 p.m. studios. I'm Molly Bloom

Autumn is one of my favorite times of year pumpkin spice lattes, cozy sweaters

and crunching through the fallen leaves in the yard.

After all the green trees turn brilliant chains of orange, yellow, and red, they gently

waft to the ground where they can be scooped into giant piles just perfect for jumping in.

But you know who doesn't get in on the leaf party? Evergreen trees.

Those include pines, furs, and spruces, and they have needles instead of leaves.

One of our listeners wanted to know what happens to them.

My name is Ava from Michigan.

My question is, why do pine trees not lose their needles in the winter like how other trees lose their leaves?

So leaves are

so leaves are very expensive to make. My name is Diana Masias.

I am a PhD student at the University of New Mexico.

I am a forest ecologist. at the University of New Mexico.

I am a forest psychologist that studies how different populations of trees respond to drought.

There are a lot of different strategies that different plants have evolved to deal with these costs and so some trees like deciduous trees make new leaves every year

whereas some trees like evergreen trees invest a lot in their

needles and retain them or keep them. So those are the trees that don't lose their

needles. In addition to energy costs is water preservation.

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