Panel 3

Panel 3 – The Past Informs the Future


Panel 3In Panel 3, The Past Informs the Future, you’ll learn how observing the history of our forests can help us manage them today.

A Century of Change

European settlement brought many changes to our forests. Livestock removed much of the native grass cover that fueled low-intensity fires and killed pine seedlings. These “cool” fires were suppressed as part of a national policy to protect grass and timber. And then, logging harvested the largest, most fire-proof trees. The result was a changed landscape dominated by thickets of smaller diameter trees that now provide the fuel source for the hot, severe wildfires we experience today.

Our Window into the Forest Past


We can recreate what our forest looked like before Europeans arrived, studying evidence left from logging and surviving old-tree relics. Logs and stumps from trees harvested here 100 years ago are still present and can be counted and mapped. The evidence here suggests there were just 16 large “yellow” pines per acre, as shown on the plot map below.

Today’s Forest

Today’s forest management restores forest structure and tree density to a more stable, sustainable form by thinning small diameter trees and leaving the bigger, more mature ones. Forest managers thing the forest based on the evidence at hand—old, live trees, stumps and downed logs—which shows us what each site should look like.

Before thinning in 2010, around 325 live young “blackjack” pine trees per acre were scattered across this site, 20 times the historic forest density, as shown on the plot map below. With thinning, blackjack pine density ws reduced by half to around 165 live trees per acre—still much higher than what historically grew—informing us that another round of thinning is needed.

Forest Plot Map


Click the images below for activity pages.

Panel 3 Activity