Analyzing Fire Data
Take a look at the graphs below. Notice how Douglas-firs
(PSME) began to increase in basal area* two years after the burn.
The prescribed fire in the plots occurred after "pre"
on the graphs.
Why do you think tree growth began to increase two years after
the burn in the graph above and not the first year?
Now look at the graph below. Pay particular attention to the decrease
in trees per acre.
The prescribed fire at Company Creek and at Boulder helped to reduce
trees in the two plots. Notice how tree density reduced significantly
in the first year after the burn.
When trees are packed tightly together it is difficult for some
light-loving species to survive. Those species need forest openings
for their seedlings to grow. If tree density is not reduced, other
shade-loving species begin to take over the forest. As habitat changes
because of lack of natural wildfire, the ecology of the landscape
changes. Dense forests also significantly increase the possibility
of hot, destructive fires in dry climate regimes**.
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