Air Date: Week of March 2, 2012

Cherry Trees and Jefferson Memorial. (National Cherry Blossom Festival)

The cherry trees in Washington D.C. will soon be bursting with blossoms for the 100th year. Over a million people are expected to celebrate this landmark anniversary at the National Cherry Blossom Festival later this month. Host Bruce Gellerman asks Margaret Pooler, a plant geneticist with the National Arboretum, whether this winter’s unseasonably warm weather will affect the centennial blossoming.

Transcript

GELLERMAN: The cherry trees in Washington D.C. will soon be busting out all over. It was a hundred years ago, back in 1912, that Japan gave the U.S. a small forest worth of cherry trees. A gift from the people of Japan to America. The cherry trees were planted along the Tidal Basin in the nation's capital and their pink and white flowers are a sure sign that spring has sprung.

During the 100th anniversary National Cherry Blossom Festival later this month, more than a million people will stop and smell the flowers and take in the intoxicating sight. For a bit more history and perspective, we turn to Margaret Pooler. She's a plant geneticist with the National Arboretum. Margaret, welcome to Living on Earth.

POOLER: Thank you!

GELLERMAN: So, 100 years. Congratulations!

POOLER: Yeah, pretty amazing, huh?

GELLERMAN: Yeah, it’s incredible. Whose idea was it to plant the trees in the first place?

POOLER: Well, it was kind of a team effort, I think. I give a lot of credit to USDA employee David Fairchild who sort of introduced flowering cherries to the U.S., but really it was first lady Helen Taft who made it happen, who had this vision of transforming Potomac Park into a field of cherries.

GELLERMAN: And the Japanese donated the trees.

POOLER: Definitely, yup.

GELLERMAN: How many trees are there today?

POOLER: Well the original gift it was over 3,000 trees, and so there’s more than that now.

GELLERMAN: Are there any original trees that were planted way back in 1912?

POOLER: Yes, there are. Believe it or not, there are some trees that are celebrating their 100 anniversary of being planted there.

GELLERMAN: I was reading that after Pearl Harbor, when we went to war with Japan, four of the trees were actually cut down.

POOLER: Well, I guess, you know, that’s because they were sort of associated with Japan. I think its kind of interesting how that has evolved, and that now we have all kinds of changes in Washington all the time, but those cherry trees are sort of just this constant. I think people have, sort of, come to depend upon their predictability.

GELLERMAN: Well, how predictable are the buddings and blossomings of the cherry trees?

POOLER: Well, I think, we know that they’re going to bloom. I know a lot of people have talked, especially this year because we’ve had such a warm winter and spring, so people are wondering what’s going to happen to these trees, is this going to have an impact on them? But, interestingly, although we’re kind of confused by the spring, the trees really are not going to really be affected by it other than probably blooming a little earlier than usual.

GELLERMAN: So the fact that this was the fourth warmest February on record won’t confuse the trees?

POOLER: It won’t confuse the trees, believe it or not, because what happens is the trees during the winter, they actually go dormant. But in the spring, the sap starts to move and the bud start to spring and color up, and that’s already going on right now. So, really, they just respond to day length and temperature, and are going to bloom no matter what.

GELERMAN: What’s the earliest do you know that they started blooming?

POOLER: I think the earliest on record for peak bloom was March 15th.

GELLERMAN: So, how long do the blossoms stay?

POOLER: Um, the blooms can last anywhere from a week to two weeks and it depends a lot on the weather. Like if we get a lot of rain and wind they’re going to last a less time.

GELLERMAN: So, do you go out and walk the Tidal Basin when they’re coming up?

POOLER: I do. I try to get down there to see the cherry blossoms. It’s very crowded though, especially at the peak of the bloom, but yeah, I think it’s definitely worthwhile seeing.

GELLERMAN: I know when the blooms come off, it looks like this gentle snowfall.

POOLER: Oh, yeah, it’s beautiful! I’m kind of lucky though. At the Arboretum we also have our own collection of cherries, and they’re different then the Tidal Basin because instead of being mostly one type, we have so many different species and cultivars. We get a longer bloom time; it usually lasts for about a month. And it’s so many different colors and sizes and shapes and forms so it’s beautiful but in a different way than in the Tidal Basin.

GELLERMAN: How many different types of cherry trees are there around the Tidal Basin?

POOLER: Around the Tidal Basin there’s probably two or three prominent varieties ¬– and that’s the Yoshino which is what sort of everyone associates with it. There’s also Kwanzan that has double flowers, and there’s also one called Prunus takesimensis.

GELLERMAN: Do you have a favorite?

POOLER: Um, my favorite is Prunus sargentii, the sargent cherry.

GELLERMAN: And, why’s that?

POOLER: Well, I like it because it’s pretty hardy, it’s vigorous. It has really beautiful single pink flowers. That’s the one I like.

GELLERMAN: Now, these are cherry trees, but no fruit, no cherry.

POOLER: Well, actually, they do – the Yoshino trees around the Tidal Basin do actually set fruit. But you don't see that many fruit because the birds usually take care of it before it even drops to the ground.

GELLERMAN: So, Margaret Pooler, how are you going to commemorate the 100th anniversary of the cherry trees?

POOLER: Well, at the Arboretum we’re going to be doing pollinations to try to create, develop new varieties of flowing cherry trees by making crosses with different species.

GELLERMAN: And, what happens to them?

POOLER: Those we then test and, hopefully, release as new cultivars so we can sort of broaden the genetic base of the flowering cherry trees that are planted in the U.S.

GELLERMAN: Can people buy them?

POOLER: They can. Once we release them, they go out to nursery owners and propagators who then sell it via their retailers.

GELLERMAN: Well, Margaret Pooler, thank you so very much.

POOLER: You’re welcome. Glad to talk with you.

GELLERMAN: Margaret Pooler is a research geneticist with the National Arboretum. And, Margaret? Happy Spring!

POOLER: Thank you, and to you, too!

GELLERMAN: And this just in - according to the National Park's official blossom predictor, peak bloom will be from March 24th .

 

Links

National Cherry Blossom Festival

National Parks Service