>> CATHY: MINNESOTA'S FORESTS ARE CHANGING ALONG WITH THE CLIMATE.

OUR NORTHERN BOREAL FORESTS ARE PART OF A MUCH LARGER EKE SO SYSTEM THAT'S UNDER STRESS BECAUSE OF RISING TEMPERATURES, AND AS WE'VE JUST SEEN, INCREASED RISK OF WILD FIRES.

LEE FRELICH IS THE DIRECTOR OF THE UNIVERSITY OF MINNESOTA'S CENTER FOR FOREST ECOLOGY.

HE JOINS US NOW WITH A LOOK AT OUR FOREST FUTURE.

WELCOME BACK.

SO WE SHOULD SAY, AND OF COURSE YOU KNOW THIS, WILDFIRES ARE AN IMPORTANT PART OF HOW A FOREST REGENERATES, BUT I AM WONDERING, PROFESSOR, IF THERE'S A DOUBLE WHAMMY HERE WITH CLIMATE HANGE LAYERED ON TOP OF ANY?

>> YES, THERE IS.

SO IT GETS WARMER EARLIER IN THE SPRING.

STAYS ARMER LONGER IN THE FALL.

THERE'S A LOT MORE TIME FOR EVAPORATION.

IN ADDITION TO THAT, OUR EARLY SUCCESSIONAL FOREST THAT HAD BEEN CUT BY THE EUROPEAN SETTLERS WERE BIRCH AND ASPEN, AND NOW THEY'VE SUCCEEDED TO INTERPRETERS.

WE'VE HAD A RETURN OF SEVERAL BIG FIRES IN THE LAST 20 YEARS.

>> Eric: O MANAGEMENT.

FOREST CHANGES DUE TO THESE CONDITIONST CHANGING?

>> YES, AND IT'S AFFECTS THE FOREST TOO.

SO LOGGING CAN CHANGE IT TO BIRCH AND ASPEN, WHICH IS WAY LESS FLAMMABLE.

AND EXTREMELY FREQUENT FIRE OR WIND STORMS FOLLOWED BY FIRE CAN ALSO EXTERMINATE THE CONFERS AND CHANGE IT TO BIRCH AND ASPEN.

WE'RE ACTUALLY SEEING THAT HAPPEN THROUGHOUT THE BOREAL FOREST, IN ALASKA, ACROSS CANADA AND NORTHERN SCANDINAVIA, AND EVENTUAL THERE'LL BE SO MUCH BIRCH AND ASPEN, IT'LL PUT A DAM PER ON THE FIRES.

BUT THAT'S DECADES AWAY.

>> Cathy: I'M WONDERING ABOUT HOW CLIMATE CHANGE MIGHT FUEL, IF THAT'S THE RIGHT WORD TO USE, AN INFESTATION OF PESTST LIKE THE SPRUCE BUDWORM COMES TO MIND, WHICH CAN REALLY CAUSE HAVOC.

>> YEAH, WHEN THE TREES ARE UNDER DROUGHT STRESS, THEY CAN'T DEFEND THEMSELVES AGAINST INSECTS AND WARMER CLIMATES MEAN THAT SOME INSECTS CAN HAVE TWO GENERATIONS IN ONE SUMMER INSTEAD OF JUST ONE, SO THEY CAN HAVE AN UTBREAK.

SO YEAH, CLIMATED CHANGE INTERACTS WITH INSECTS AND THEY INTERACT WITH FIERES BY CREATING DEAD TREES.

WIND STORMS ARE MORE SEVERE THAN THEY USED TO BE IN NORTHERN MINNESOTA.

THEY CREATE DEAD TREES THAT ARE SUSCEPTIBLE TO BURNING, AND SO IT'S LIKE EVERYTHING GOING IN THE ONCE IN THE DIRECTION OF BIG FIRES.

>> Cathy: I REMEMBER WHEN YOU WERE AST ON THE SHOW, HERE'S THE QUOTE, YOU SAID THAT YOU WERE PRETTY WORRIED THAT MINNESOTA WILL START LOOKING LIKE KANSAS SOON.

WELL, FAIRLY SOON.

>> YEAH, MY 2070, IT EASILY COULD.

IF EVAPORATION STARTS TO OUTSTRIP PRECIPITATION.

SO WE GET A NEGATIVE WATER BALANCE.

AND UR CURRENT PROJECTIONS SHOW THAT THE WESTERN BOUNDARY WATERS WILL BECOME PRAIRIE BY THE END OF THIS CENTURY.

WHEREAS THE EASTERN BOUNDARY WATERS IS MORE LIKELY TO TRANSITION FROM BOREAL FOREST TO TEMPERATE FOREST WHICH IS MAPLE AND OAK.

>> Eric: SOME SOMETHING POLICY MAKERS CAN DO?

>> IT'S A LITTLE BIT TOO LATE TO CHANGE THESE THINGS.

I MEAN, THE BOREAL FOREST ASK A BIG THING, AND ONCE IT'S IN MOTION, YOU'RE NOT GOING TO STOP IT.

SO THEY SHOULD HAVE DONE SOMETHING 30 YEARS AGO.

>> Cathy: SO YOU CAN'T -- I MEAN, THERE WERE EFFORTS UNDER THE D.N.R.

'S PURVIEW.

THEY WERE PLANTING WHITE PINE UP THERE AND SOME OTHER SPEES SPECIES.

>> WELL, THE WHITE PINE S ONE OF THE MOST FLEXIBLE IN TERMS OF CLIMATE.

IT'S THE RED PINE, THE JACK PINE, AND SOME OF THE OTHER BOREAL SPECIES, HE SPRUCES THAT WOULD REALLY BE IN DAIJ DAR OF DEZ APPEARING.

THE YEAH, THE TEMPERATE WILL HAVE SOME WHITE PINE IN, BECAUSE IT'S BOTH A BOREAL AND A TEMPERATE TREE.

IT DOESN'T WANT TO BE CLASSIFIED.

>> Eric: I FOUND SOME OPTIMISM.

YOU SAY THAT THE OUTDOOR RECREATION BENEFITS WILL BE GOOD EXCEPT FOR CROSS-COUNTRY SKIING.

>> YEAH, YEAH, THE LONGER THE WARM EASON, IT TURNS OUT, THE MORE RECREATION THERE IS.

YEAH, WE JUST ID A STUDY OF THAT.

I JOINED FORCES WITH AN ECONOMIST, BELIEVE IT OR NOT, AND VERY INTERESTING TO SEE THAT THERE WOULD BE A LOT MORE RECREATIONAL USE IN A WARMER CLIMATE.

>> Eric: DEER HUNTERS?

>> YEAH.

>> Eric: WHAT'S IN IT FOR THEM?

>> MORE DEER IN A WARMER CLIMATE IN NORTHERN MINNESOTA?

>> Cathy: YEAH, BUT DON'T THEY CAUSE HAVOC WITH TREES?

>> THEY DO WITH CERTAIN SPECIES LIKE WHITE CEDAR AND WHITE PINE, BUT A WARMER CLIMATE WILL ALLOW MORE DEER TO SURVIVE THERE.

>> Eric: HAVE YOU GOT I TOLD YOU SO BONE IN YOUR BODY?

>> YEAH, I DO.

ACTUALLY, I DECIDED THIS WAS GOING TO HAPPEN IN 1988 WHEN WE HAD THAT REALLY HOT SUMMER.

AND A ROT OF YEARS HAVE GONE BY SINCE THEN AND IT LOOKS LIKE WHAT I THOUGHT WAS GOING TO HAPPEN IS PRETTY MUCH HAPPENING.

>> Cathy: THAT'S DEPRESSIONING, THOUGH?

>> YEAH, IT'S DEPRESSING TO BE RIGHT ALL THE TIME.

>> Eric: APPRECIATE YOUR KNOWLEDGE.

>> YEAH, USER W