Is That Spring Bursting Out, or Climate Change?

Is That Spring Bursting Out, or Climate Change?

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What are the chances that global climate change is messing with our seasons? Pretty good, say some climate scientists who’ve been studying color satellite images of the U.S. gathered since the early 1980s.  They say the photos show that Spring’s been arriving, on average, about eight hours earlier every year.  Nobody knows exactly what that means.  But there’s a way for every Chicago area gardener to help figure it out.

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There are more than 11-hundred Lilac bushes in Lombard’s Lilacia Park, and lots of them have been around since the Civil War. Col. William Plum planted them in the early 1920s, on what was then his estate.

BUDD: Well you can see that the buds are starting to swell a little, which is a good sign for Spring, I guess.

Horticulturist Jerry Budd takes care of these hardy old shrubs, and he likes the healthy way they look right now.

BUDD: Real healthy, actually. That’s good. It’s what we like.

Every May, Lombard hosts its Lilac festival - with a parade, and a queen - and it’s been going on pretty much since this became a public park in 1927. Now, nobody knows for sure, because they didn’t keep precise records, but Jackie Bruzinski, who’s worked here for quite a while, has noticed something.

BRUZINSKI: Statistically, according to our records the bloom has been moving up a little bit .

That little bit has been pushing the flowering peak from around Mother’s Day to early May.

DAVIS: And has that been more recent?

BRUZINSKI: That would be about five years ago.

Lilacs, it turns out, are pretty valuable tools in determining the state of our climate. They’re found all over the country, and they have distinctive bud bursts, leaf-outs and blooms. And there’s someone who’s very curious about that bush out back by your garage.

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HAVENS: Project Budburst is a program that engages citizens to make observations about when plants leaf out and when they bloom. And we use this data to help predict how plants are going to respond to climate change.

Kay Havens runs Project BudBurst, a Web site at the Chicago Botanic Garden. The staff’s working with a number of botanic gardens and land management agencies across the country, and they have about 60 species of trees and garden plants they want to track.

They’re doing it by asking citizens to log on and report about their own yards. When they piloted Budburst last year, they got 500 participants, many of them students. This year, they want at least 5,000 reporters - all in the next two months or so.

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HAVENS: Well, we’re coming into the bulb garden here, and you can see one of our earliest Spring flowers already in bloom. This is snowdrops, little white flower.

This is how it all gets complicated. Separating out weather from climate . Snowdrops are opportunist little garden fairies that pop up through the snow whenever they can, so their bloom times vary wildly.

HAVENS: Right, so this is one of the flowers we’ve been tracking at the garden for many years, and you can see last year, January 3rd, we see the first flower open. This year, although we had buds in early January the snowfall stopped them from blooming and now they’re blooming, on March 14 was the first date.

Yes, it’s been a long winter. And years like this can mess up long-range research. That’s why decades of precise data are needed. And if Spring really is starting earlier, it’s not just academic. Kay Havens says it can have disastrous results.

HAVENS: One of the reasons we’re concerned about this is if plants really are flowering a week, two weeks, three weeks earlier but the pollinators are delayed coming out, we’ll see a mismatch between plant bloom and pollinator availability. And without those pollinators they can’t set seeds. And that’s when we’ll start to see species going extinct.

Or migrating. If a plant’s lucky enough, it might manage to transport its seed someplace north or to a higher elevation, so its progeny can survive elsewhere. But if we’re getting warmer, it means invaders from the south aren’t far away. And we’re not necessarily talking pretty palm trees along Michigan Avenue.

HAVENS: For example we’re already seeing kudzu march up, a horrible weed, uh, we discovered that a few years ago in Evanston, where it had been living happily for eight years along the Metra line.

DAVIS: Kudzu?

HAVENS: Kudzu.

DAVIS: That’s kinda scary, isn’t it?

HAVENS: It is. The world’s gonna be a very different place in twenty to fifty years.

The Botanic Garden says it wants to keep Project Budburst going for at least a decade if it can. And, this year, the staff is able to record historic data. So if you’ve been keeping a garden journal observing your forsythia or your Virginia Bluebells over the years, or if you just want to get the kids involved this spring, now’s the time to start dishing the data. Not much of a gardener? Well, Kay Havens wants to know when your first dandelion blooms hit, too.

For Chicago Public Radio, This is Ken Davis.