Pondorosa Pine Fire Ecology
by Gene Gade
IF
YOU LOOK CLOSELY AT PONDEROSA PINE FORESTS ALMOST ANYWHERE, YOU WILL SEE
EVIDENCE OF FIRE.
THESE
SCARS ARE CAUSED BY GROUND FIRES THAT PERIODICALLY SWEEP THROUGH THIS FOREST.
FIRES THAT MOVE THROUGH SO RAPIDLY THAT THEY MAY DAMAGE A PORTION OF THE TREE
TRUNK BUT DO NOT GENERALLY KILL THE TREE.
MATURE
PONDEROSA PINE HAVE SEVERAL FEATURES THAT ALLOW THEM TO SURVIVE GROUND FIRES.
ONE THING IS THIS THICK BARK THAT PROTECTS THE TISSUES THAT CONDUCT FOOD AND
WATER AND ACCOMPLISH GROWTH IN THE PLANT.
AS
THEY GET OLDER PONDEROSA PINE NATURALLY LOSE THEIR LOWER BRANCHES, WHICH MAKES
IT HARDER FOR THE FAST MOVING GROUND FIRES TO REACH THE CROWN.
FIRE
IS A NATURAL, RECURRING ASPECT OF THE ECOLOGY WHERE PONDEROSA PINES GROW.
TREE
RING DATA AND HISTORICAL PHOTOS SUCH AS THESE FROM CUSTER'S 1874 EXPEDITION
INDICATE THAT FIRE WAS THEN FREQUENT IN THE BLACK HILLS.
THE
NATURAL RESULT WAS A PINE SAVANNA,
WIDELY SPACED TREES WITH GRASSES AND WILDFLOWERS ON THE FOREST FLOOR.
WE
CAN SEE IN THIS PHOTO OF THE SAME SPOT THAT PINE TREES HAVE SPREAD TO NEW AREAS
AND THE TREES ARE MORE NUMEROUS AND CLOSER TOGETHER.
THERE
ARE MORE SMALL AND MEDIUM SIZED TREES THAT CAN CARRY FIRE TO THE CROWNS OF
MATURE TREES AND KILL THEM.
SELECTIVE
LOGGING ACCOMPLISHES MANY OF THE SAME ECOLOGICAL BENEFITS IN PONDEROSA PINE
FORESTS WITHOUT FIRE BY THINNING THEM AND REDUCING THE FUEL LOAD.
BOTH
FIRE AND HUMAN MANAGEMENT HAVE A ROLE IN KEEPING OUR FORESTS HEALTHY. I'M GENE
GADE, UNIVERSITY OF WYOMING COOPERATIVE EXTENSION SERVICE.