"One of the reasons why [dwarf mistletoe] is currently infecting or infesting [ponderosa pine] stands at a level that appears to be so damaging is partly because of the lack of fire in the ecosystems."
Now, the dwarf mistletoe, we do have in ponderosa pine, and that's throughout the West and you will see it here and in Fort Valley, and in places. And the prescriptions that are used can be modified in order to take that into account. And certainly there are particular prescriptions that are relatively extreme when the main objective is to control for dwarf mistletoe. And the main thing I'd like to say about that, about dwarf mistletoe, is that one of the reasons why it is currently infecting or infesting stands at a level that appears to be so damaging is partly because of the lack of fire in the ecosystems. Fire actually used to be able to selectively kill groups, stands, and individuals that were highly infected or infested with dwarf mistletoe. And that's because, first of all, a lot of the branches are dead. In some cases the individuals are dead.
And dwarf mistletoe also causes brooming some. The brooms—big bunches of needles and branchlets—you'll see them when we go up to the forest, certainly—are very highly flammable, and those would be really good for the fire to catch on, start that broom on fire, and then the fire would crawl up the rest of the tree, throughout the rest of the tree, killing the tree. Without the host, the dwarf mistletoe is unable to spread. It's an obligate parasite, and obviously, in a ponderosa pine forest it can spread from neighbor to neighbor. But the fires would come through the forest and be able to take out specifically—or selectively take out—a lot of those trees and groups that were highly infested. Well, by removing fire from the system, we've taken out that particular agent that was able to do that.
As far as the bark beetles go, both dwarf mistletoe and beetles have been around as long as the ponderosa pine has been around—or almost as long, but certainly as long as these forests have been around. And they're both natives and are necessary parts of the ecosystem. However, the management that has changed things in the past hundred years, certainly has its impacts. Like I said, just like with dwarf mistletoe. I think more with the beetle that we're talking about risk that severe amounts of thinning and these very open structures and the changes in the diameter structures that we're talking about with these trees may change how the bark beetles react and interact with these forests. And I think that it's something that we're going to have to learn, and another reason why we need to proceed with caution and not just headlong, before we have all of our information.