In an Illinois forest, many buds are forming earlier and leaves are changing color later » Yale Climate Connections

Transcript:

Near the University of Illinois Urbana-Champaign, a 60-acre forest called Trelease Woods has grown – largely undisturbed – for centuries.

But as the climate warms, the forest is changing.

Professor Emerita Carol Augspurger has monitored more than 60 tree and plant species there for decades – noting when buds form in spring and when leaves change color and drop in autumn.

And she and David Zaya of the Illinois Natural History Survey recently analyzed almost 30 years of data.

Zaya: “The first thing we wanted to see was if the timing of spring and autumn events was shifting.”

Zaya says for most species in Trelease Woods, spring events are occurring earlier and fall ones later. They found that the growing seasons of almost 90% of the tree species have gotten longer by an average of almost five days per decade.

These changes bring risks. If a tree buds early, it’s more vulnerable to frost damage during a cold snap. And when trees leaf out sooner, they create shade that can limit the growth of understory plants.

So over time, some species may struggle. And already one thing is clear:

Zaya: “The effects of climate change are real. It’s not theoretical. It’s not for the future.”

It’s happening now.

Reporting credit: Sarah Kennedy / ChavoBart Digital Media