Nell Greenfield Boyce

I mean, the idea is that the tree is busy scavenging all this nitrogen and nutrients to store them away for the winter.

And, you know, the red pigments, the chemical sunscreen may be protecting that chemical activity.

There are some.

Like, there's one study that looked at yellow mutants of three deciduous species that normally turn red.

Okay, so...

Yeah.

And when they shed their leaves, it turns out that those leaves had more nitrogen in them.

So the idea is maybe without the red pigments, the plants weren't able to recover that nitrogen and get it out as well as they would have normally.

And people have also noted that trees that live with nitrogen fixing bacteria.

So, you know, there's these, you know,

species that live kind of like in relationships with bacteria that help them get nitrogen.

Yeah.

So they have plenty of nitrogen and they don't seem to bother to turn red.

Oh, well, that's a really revealing detail.

Yeah.

I mean, it's it's suggestive, right?

I mean, there's a lot of kind of suggestive evidence out there.

So like Suzanne Renner told me that trees in Europe tend not to be as red as in the U.S.,

And she did the study looking at the sunlight that comes in.

Actually, you can look at it by seeing what hits solar panels.