Succession After Fire - Ponderosa Pine Fire Ecology
by Gene Gade
WILDFIRE
BURNED THIS AREA TWO WEEKS AGO.
THIS
AREA BURNED THREE YEARS AGO BY A FAST-MOVING FIRE ON A WINDY NIGHT.
IT'S
CLEAR THAT THE GRASSES WERE NOT KILLED BY THE BLAZE.
SOME
OF THE BROADLEAF FLOWERING PLANTS BECAME MORE ABUNDANT AFTER THE FIRE.
THE
WOODY SHRUBS, SUCH AS SAGEBRUSH DID NOT FAIR SO WELL.
MANY
OF THE PONDEROSA PINE WERE SCORCHED, BUT MOST WILL SURVIVE AND WILL RECOVER.
IF
WE LOOK CLOSELY, WE CAN SEE THE SEEDLINGS OF SHRUBS BEGINNING TO RECOLONIZE THE
AREA.
IN
A FEW YEARS, THE AREA WILL LOOK MUCH LIKE IT DID BEFORE THE FIRE.
IN
THIS CASE, NON-WOODY PLANTS EITHER SURVIVED THE FIRE OR RESEEDED IT QUICKLY
FROM OUTSIDE THE AREA. THEY STABILIZE
THE PLACE, PROTECT IT FROM EROSION AND BEGIN TO REBUILD THE SOIL.
LATER,
THE WOODY PLANTS TAKE HOLD - ACHIEVING DOMINANCE OVER THE PIONEERS THAT
COLONIZED THE AREA AFTER THE FIRE.
EVENTUALLY,
THE PLANT AND ANIMAL COMMUNITY WILL RESEMBLE WHAT WAS THERE BEFORE THE FIRE.
NATURE'S
RECOVERY FROM DISTURBANCES SUCH AS FIRE IS AN EXAMPLE OF A PROCESS CALLED
SECONDARY SUCCESSION. IF THE DISTURBANCE
IS NOT TOO GREAT, PLANTS AND THE ASSOCIATED ANIMALS TEND TO REPLACE THEMSELVES
IN A FAIRLY PREDICTABLE SEQUENCE RETURNING TO A STATE SIMILAR TO WHAT WAS
ORIGINALLY PRESENT.
I'M
GENE GADE OF THE UNIVERSITY OF WYOMING COOPERATIVE EXTENSION SERVICE.