Insects and diseases pose two of the most serious threats to a tree’s health. By examining specific symptoms of insect or disease damage, you can make a reasonable diagnosis of the problem and select the proper treatment.

If you are uncertain about the type of insect or disease or do not know how to treat them, contact your local CSFS Field Office to conduct a home-site assessment of the trees on your property.

Select the arrows icon on the left to display the legend and available map layers.
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Roundheaded Pine Beetle

Roundheaded pine beetle activity has affected approximately 52 percent of the ponderosa pine forest ecosystems in Dolores County since 2000.


Spruce Bark Beetle

Severe outbreaks continued in portions of the San Juan Mountains, West Elk Mountains and Sawatch Range; the southern reaches of the Sangre de Cristo Mountains; and portions of north-central Colorado.


Douglas-fir Beetle

Widespread groupings of tree mortality occurred in portions of the northern Sawatch Range; northern areas of the La Garita Mountains, south of Gunnison; the Needle Mountains near Lake City; and the San Miguel River drainage.


2020 Forest Health Report Story Map

CSFS Forest Entomologist Dr. Dan West produced an Esri Story Map for the 2020 Forest Health Report, which tells the story of how data was collected to compile the report, and offers users an interactive way to find out about forest conditions in their area.

Use the plus and minus controls on the upper left of the map to zoom in or out on a specific area.
Click the magnifying glass icon to show the search box. Enter the name of a specific town, city or location to search.
Hold and drag your mouse to scan the map.
Click on a color-highlighted area on the map to display more information about insect activity.
Mobile users may view a larger version of the map by visiting the Esri ArcGIS website.