What's The Impact Of Early Blooms?

MELISSA BLOCK, HOST:

So whatever happened to March coming in like a lion? It's been downright lamb-like lately, more like May or June temperatures than March. The colors tell the story on the weather map, a huge swath of orange and yellow across much of the country.

It was 81 degrees in Omaha and Chicago earlier this week. And it's been so warm here in Washington, D.C., that the famed cherry blossoms will be at peak bloom weeks earlier than normal. Which got us wondering - how does an early bloom affect plants? And what does it mean for bugs?

Jake Weltzin has some of the answers. He's an ecologist and the executive director of the USA National Phenology Network.

Jake, welcome to the program.

DR. JAKE WELTZIN: Thank you very much, Melissa.

BLOCK: And let's define phenology. Just a bit here: The shorthand, I gather, is nature's calendar. You're looking at the effect of climate on the lifecycles of plants and animals.

WELTZIN: Sure, phenology is sort an old-fashioned term for the study of when things appear. And what we're interested in here is the timing of spring blooms and migrations and hibernations. So we have to think about the entire season, not just when things wake up in the spring but when things go to sleep in the fall, if you will.

BLOCK: OK. And you've been collecting data from people all over the country. What examples have you gotten so far this spring about when things have appeared?

WELTZIN: Well, it's a weird spring this year, that's for sure. Sap is flowing early in Vermont and New Hampshire in the maple trees, and so we have to think about the timing of maple syrup production. Lilacs are coming out very early. In the Milwaukee area, we've got flowering fruit trees that have been out and done already and are producing fruits in Georgia. So we have all hosts of odd things happening this spring.

BLOCK: You know, I remember thinking when I saw my daffodils coming up super early this year that I just sort of wanted to push them back under the ground.

(SOUNDBITE OF LAUGHTER)

BLOCK: Go back in there where it's safe. If a plant or tree does bloom or leaf out early, does that affect its seasonal cycle for the rest of the year?

WELTZIN: We don't really know for a lot of plants. And we're just starting to get that information organized. Some plans do, indeed, have a deterministic lifecycle, which means that if they come up early they will shut down early. Others are indeterministic and they'll grow and grow and grow all season long.

BLOCK: You know, when you think about this you inevitably think about possible role of climate change. Does this pattern to you seem like a fluke, just a one-time thing, or a reflection that you that you've been seeing of a trend over a number of years?

WELTZIN: We are seeing strong trends almost wherever we look. In the last decade, we're actually now starting to be able to say OK, well, we see patterns of plants and animals coming earlier. And we have better and better climatological records, temperature records, and we can start to link those together. And there's a paper coming out it seems every week now that's saying OK, here's a trend in bees coming out 10 days earlier over the last 130 years, and we can attribute that to warming temperatures.

BLOCK: Since we're seeing these were temperatures so early, what does that mean for insects? Are we going to be seeing a really big swarm this year?

WELTZIN: That's an excellent question and we are worried about that, because some bugs are good and some bugs are bad. Some bugs do pollination services for us and they pollinate plants so we can have fruits and crops. Others carry diseases. And there're so many different kinds of bugs, it's hard to know exactly what all those patterns might be. But we sure don't want to have West Nile virus coming earlier in the year when the bugs come earlier.

So, generally yes, you would find a strong relationship between the timing of flowering and insect activity. They're both driven by temperatures. In fact, we're seeing some cases where insects like bees are tracking plant flowering.

BLOCK: Jake Weltzin with the US Phenology Network, thanks so much for being with us and happy spring or early summer - whichever it is

WELTZIN: Thank you.

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