Hi, I'm Iraflato, and you're listening to Science Friday. Today on the podcast, to paraphrase Sondheim, we go into the woods.

First, an update on efforts to restore the American chestnut. These trees once towered over the landscape, dominating forests in parts of the eastern U.S.

They provided food for people and animals, and they were a hugely valuable source of lumber.

But in the late 1800s, a fungal blight in the U.S. virtually wiped out the American chestnut plants across the country.

Streets once lined with beautiful trees went bare. And due to the blight, the species now

exist mainly as a shrubby plant, not as a towering tree. But new genetic work could help

speed up breeding efforts to add fungal resistance to create a heartier chestnut population.

Joining me now is Jared Westbrook. He's director of science for the American Chestnut Foundation.

Welcome to Science Friday. Hello, Ira. Nice to have you. We've talked about chestnut restoration efforts.

How long has it been going on?

Where does the project now stand?

So chestnut restoration in the U.S. has been going on since the 1920s.

And people have tried a lot of different things.

First, the trees got the blight originally from imported Chinese and Japanese chestnuts that were brought over,

and they had the blight pathogen on these trees.

And the Japanese and the Chinese chestnuts actually are interfertile when you cross them and breed them with American chestnuts.

So the early efforts were in hybridization between the Asian species and the American species.

With the American Chestnut Foundation breeding program, we've been doing this for 40 years.

And we have been doing this program called Backcrossing, where we take the Chinese and the American hybrids and we cross them back to a lot of

different surviving wild trees. People tell us, oh, there's a flowering tree near the side of the road,

and we then give them pollen from some of our hybrid trees that we've selected for having

improved blight resistance, and then they have bred those hybrids with diverse American

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