The Forest Service is tacking verbenone patches to protect campground trees from Mountain Pine Beetles.
Verbenone is a pheromone, or chemical, that tells beetles to go away.
The beetles should be arriving in a couple weeks.
The Forest Service doesn't have much time to get the word out. Foresters are stapling verbenone patches to Charles Waters' campground's beautiful old pine trees.
"It's like a big no vacancy sign," said forest service spokesman Tod McKay.
Foresters put a patch up about every 40 feet. They have about 200 patches for this Stevensville area campground. With 1.6 million acres of forest, foresters can't put a no vacancy on every tree.
"It's too expensive," said McKay. "We have to be selective."
It cost about $3,000 for 1,000 patches.
Foresters are treating high use areas like campgrounds and trail heads.
The patch needs to stay on the tree all summer. But you need to apply a new patch next year, and the year after that.