September 20, 2022 — The leaves change color in the North Country. It is one of the first places to see fall foliage in New York. But this year, colors may come and go from the trees faster due to drought conditions across the state. Taryn Bauerle, a plant ecophysiologist at Cornell University, says the effects of climate change could impact the future of leaf-watching in New York City.
Taryn Bauerle: Around [the Ithaca] area, as well as around town and Long Island, and I think also more of the western part of the state, experienced moderate drought. So even though we received some precipitation locally, and more recently, I don’t think it was really enough to alleviate all the dryness that we accumulated over the summer months.
EMILIA RUSSELL: What does this mean for when and what kind of fall foliage we might see this fall?
BAUERL: Usually this means the timing will be a little earlier. Plants are under a little more stress and therefore tend to start changing their leaves a little earlier and then finish changing a little earlier as well. So they don’t tend to keep those leaves for as long. If it is a more extreme drought event, we could have very reduced colorfastness. So the leaves tend, as you can imagine, to turn brown and shrivel up before they can even achieve those beautiful colors.
RUSSEL: Have you seen a shift in the timeline over the past few years or decades, due to something like climate change?
BAUERL: for New York, we are certainly experiencing changes in our climate. I wouldn’t say there are dramatic or extreme changes, especially from year to year. When we look at long-term trends, we may find changes there. But I didn’t really see that for New York, or like I said, at least something that we would really notice a lot. It can be on the order of a few days here or there. But it is certainly a possibility to move forward in the future. For example, New York hasn’t really had a lot of droughts, but they seem to be spreading. And if so, we might see more changes in the future.
RUSSEL: What is actually going on inside a tree or inside a leaf that actually causes it to change color to a bright yellow, orange or red?
BAUERL: What essentially happens is that the green color of the leaves – so the chlorophyll that we see visually – breaks down and essentially unmasks the other colors that are often present even when the chlorophyll is there or sometimes produced later in the season . So we can see those colors before the leaves fall and that’s because the days get shorter and the nights get cooler, the plants – at least the deciduous trees in this case – stop producing chlorophyll because it is a very energy-intensive process. And they cut those leaves off the main stem of the tree before it falls.
RUSSEL: Are you into leaf watching?
BAUERL: A little, yeah, I mean I like it. Of course, it’s so beautiful.
RUSSEL: Do you have a favorite place you like to go or a favorite way to see the leaves change?
BAUERL: Well, I’ve done a lot of work in our local forests here [in Ithaca]. Mount Pleasant is the one not far from us. It’s often a place where in the fall we take samples, and it’s on a little raised knoll, so temperatures tend to be a bit cooler than Ithaca and it’s a really nice place to see the fall foliage. But I’m also a hiker so anyone grabs me and I’m happy to go anywhere in NYC if I get the chance.
RUSSEL: As someone who studies plants and droughts, what concerns you most about fall foliage?
BAUERL: Really the biggest question, which I have to admit I don’t have a good answer to, is what will happen in the future? And that’s a big question there because we have these very different seasons and more erratic seasons, I would say. And so that’s the big question mark. I need to think about it a lot more, but I think people should be aware and think about it more, because these trees only have a limited number of mechanisms at their disposal to deal with our changing climate. We want to preserve them not just for their beauty and everything for us, but for all the ecosystem services they provide to us as well.