
The Mountain pine beetle (Dendroctonus ponderosae) is back in Jefferson County. This little bug, this native to the western North American pine forests, is responsible for the periodic loss of millions of pine trees – most normally Ponderosa, Lodgepole, Scotch and Limber pines.
Mountain pine beetles (MPB) are always with us, having evolved with the western pine forests. Under ideal conditions, their attacks are low-level, limited to trees that have been stressed due to injuries, drought, over-crowding, fire damage, root disease or old age. However, every 10-30 years, whether due to beetle population explosions, enhanced drought, or warmer temperatures (or all three), major outbreaks occur. The last major MPB outbreak in Jeffco occurred from 1996 to 2004. Since 2023 there have been signs of a new resurgence of MPB in our area.
Read more