Evergreen trees shedding needles in the foothills in Southwest Colorado may be going through an annual ritual - not dying from bark beetles.
Evergreens that are beginning to shed needles look different than beetle-killed conifers, the Colorado State Forest Service said in a statement.
The difference can be seen in conifers in La Plata, Archuleta, San Juan, Dolores and Montezuma counties.
Needles on beetle-infested trees typically change color throughout the entire tree. The color goes from an off-green to reddish-orange. The trees also will show other signs of beetle attack, such as popcorn-shaped pitch tubes on the trunk and boring dust at the base of the tree.
Needles on evergreens not infested by beetles commonly shed needles on the lower portion of the crown or those closest to the trunk.
The needles typically turn yellow, then reddish-brown before falling. Trees stressed by drought or root damage may shed more needles to keep the tree in balance with its root system.
