Grand Junction Field Office – Insects & Diseases
Insects and diseases can pose serious threats to a forest’s health both in our native forests and in our urban forests.
Quick Links
Common Insect & Diseases of Western Colorado
If your questions cannot be resolved with the information provided, please contact your local field office. Foresters are available for to discuss specific insect or disease concerns on your property. Samples of the problem also can be sent to our state entomologist in Fort Collins for further investigation.
Ash
- Lilac ash borer (3.2 MB PDF)
Junipers
- Juniper borers (1.7 MB PDF)
- Juniper mistletoe (2.2 MB PDF)
Spruce species
- Spruce bark beetle (500 KB PDF)
- White pine weevil (2.8 MB PDF)
Pine species
- Black-leaf pine scale
- Dwarf mistletoe management
- Mountain pine beetle (10.7 MB PDF)
Piñon pine
- Piñon Ips bark beetle quick guide (5.3 MB PDF)
- Pinon Ips Identification Handout (5.7 MB PDF)
- Protecting your piñon trees (415 KB PDF)
- Twig beetle (109 KB PDF)
- Piñon pitch mass borer (450 KB PDF)
- Piñon blister rust (280 KB PDF)
- Piñon dwarf mistletoe (700 KB PDF)
Poplar species
-
Fire blight Aspen scale (305 KB PDF)
- Oystershell scale (2.6 MB PDF)
- Poplar borer (1.7 MB PDF)
- Sudden aspen decline (2.3 MB PDF)
Other common pests
- Douglas-fir bark beetle (600 KB PDF)
- Elm seed beetle (3.1 MB PDF)
- Fire blight (1.1 MB PDF)
If you are concerned that your tree is susceptible to bark beetles, please read this fact sheet (2.4 MB PDF). It will help you identify what type of tree you have, determine the tree’s susceptibility and decide if your tree has been attacked. The fact sheet also gives tips on how to prevent bark beetles from attacking your trees.
The Colorado State Forest Service and the Colorado State University Extension office have worked together to create factsheets on a wide range of subjects including native and exotic insects and diseases, in addition to the ones listed above. To access the library of publications, visit the CSU Extension publications web page.
The Annual Forest Health Report provides an overview of insect and disease conditions in all of the state’s forests.
For additional information, visit the CSFS Insects & Diseases page.
Please contact the Grand Junction Field Office with any questions.
Forest Insect & Disease Aerial Survey
The annual survey is led, coordinated and funded by U.S. Forest Service – Health Protection personnel. A small fixed-wing aircraft is flown between 1,000 to 1,500 feet above the treetops while surveyors mark the location, number and identity of trees affected by insects or diseases on a map. The CSFS has assisted in the aerial survey since the 1970s and began playing a larger role in 1997.
For more information about the Colorado aerial survey, visit the U.S. Forest Service Rocky Mountain Region website.