Starting Monday, Cheyenne's Urban Forestry division will begin spraying for bark beetles throughout the city.
Spraying will go from 4 a.m. to noon each work day, starting with trees in Lions Park.
Urban Forestry will be spraying the trunks of pine and spruce trees.
Once a tree is infected with bark beetle it only takes one to two seasons before the beetle kills it.
According to survey's done last year, Urban Forestry has discovered mountain pine beetle numbers are dwindling, but spruce bark beetle numbers are on the rise.
"The spruce bark beetle is increasing in number. There's also another bark beetle, it's called the Ips bark beetle and it's associated with pine's and spruce and between the Ips bark beetle and the spruce or mountain pine beetle they can really create havoc on a tree," said Randy Overstreet, Assistant Director of Cheyenne Urban Forestry.
Urban Forestry says all trees being sprayed will be clearly marked.
They ask that residents stay out of spray areas until spray has dried on the trees and ground beneath the trees and keep your pets away too.